(This article was originally published on EurekAlert! on April 19, 2022)
A research team led by scientists from the Hong Kong University of Science and Technology (HKUST) has revealed how secondary structure RNA elements control the cleavage activity of the DICER enzyme in both pre-miRNA and short-hairpin RNAs, improving the understanding of the DICER cleavage mechanism and providing a foundation for the design of accurate and efficient short-hairpin RNAs for gene-silencing.
In humans, microRNAs (miRNAs) govern multiple biological processes and play essential roles in various cellular functions. These small RNAs regulate the level of messenger RNAs (mRNAs) used to make proteins. The dysfunction in mRNA regulation caused by an anomaly in miRNA sequences or expressions is linked with various human diseases, including cancers and neurodegenerative and infectious diseases, making it a useful biomarker for disease diagnosis, prognosis, and drugs for treatments in the biomedical aspect.
The accuracy of miRNA sequences and expression is mainly determined by miRNA biogenesis, a process which involves DICER cleaving miRNA precursors (pre-miRNAs) to generate miRNAs. Therefore, DICER cleavage controls miRNA expression and sequences, and thus its cleavage impacts miRNA functions. In addition, the cleavage of DICER has been exploited in a widely-used shRNA (i.e., short-hairpin RNAs) gene silencing technology. DICER plays a critical part in this technology by cleaving shRNAs into siRNAs, subsequently silencing targeted mRNAs. shRNAs have been widely used in biological research and have also found their way into biomedical therapies.
In a paper published in Nature Communications on April 19, 2022, the research team, led by Prof. Tuan Anh NGUYEN, Assistant Professor in the Division of Life Science at HKUST, discovered the constructive role of a secondary RNA element called 22-bulge in the cleavage activity of DICER on shRNAs and human pre-miRNAs.
By designing innovative artificial substrate models called two-loop shRNAs, the team were able to conduct high-throughput cleavage assays with more than 20,000 shRNAs containing different sequences and re-construct uncleaved shRNA sequences from the cleaved products. Using next-generation sequencing and computational analysis, they successfully monitored the activity of DICER cleavage for 20,000 different shRNAs at the same time and comprehensively identified various stem-loop junction structures that control the different cleavage features of DICER, including cleavage sites, double cleavages, single cleavages, and cleavage efficiency.
“Excitingly, among many secondary RNA elements we found in this study, we identified a single-nucleotide element, called 22-bulges, that exhibits the highest cleavage accuracy and efficiency of DICER on shRNAs and pre-miRNAs,” said Prof. Nguyen. “Therefore, 22-bulges facilitate shRNAs' knock-down (KD) efficiency, allowing us to design a more effective shRNAs used in gene silencing technology. In addition, 22-bulges are also found in many pre-miRNAs and are critical for proper miRNA production in human cells.”
“Our work allows us to understand the molecular mechanism of DICER cleavage and explain the functions of the secondary structure RNA elements in pre-miRNAs/shRNAs in controlling miRNA biogenesis and KD activity of shRNAs,” another co-first author and Prof. Nguyen’s student Trung Duc NGUYEN explained. “In an application perspective, our findings provide an alternative approach to improve the current shRNA design for gene-silencing technology with higher KD efficiency and less off-target effect.”
Minnie SOO and CHOW Hiu-Yau became Hong Kong’s sports stars, when the former bagged the city’s first-ever bronze medal at the Tokyo 2020 table tennis women’s team event, and the latter captured a bronze medal at the 2019 Asian Open Figure Skating Trophy. Among the whirlwind of international competitions and training sessions that occupied much of their lives, it would seem that something was missing for them.
The missing puzzle piece? School
“I have missed school dearly for 10 years,” says Minnie. “I turned pro when I was at Form 3. While initially I thought I would return to school after a couple of years, it turns out the competitions have kept me immersed in training every day. I miss classes and school life so badly that sometimes I dream about going back to school and feel sad waking up.”
After spending 10 years playing professional table tennis at the highest level, the 23-year-old has come to realize that she needs to plan ahead while still young.
“A few months ago, I began suffering from yips, a nerve injury that entails pain and spasms to my strong hand when I was trying to conduct repetitions,” says Minnie. “While I took time off to heal my injury, I read, think, and review my options ahead, including a return to school. The injury put things into perspective for me. Then I applied for HKUST, because of its reputation and my sister, who also graduated from here.”
Now it is a dream come true. Minnie has been admitted to HKUST School of Science via the Student Athlete Admission Scheme (SAAS), and will be starting university in the 2022/23 academic year. She is the first local student athlete admitted mainly based on sports achievements, due to a recent enhancement of the scheme to provide more flexible admission and assistance to top local athlete applicants.
“Hong Kong athletes currently lack options to pursue a second career outside of sports. HKUST aspires to provide them with the proper assistance and guidance to chase after their dreams and interests, as long as they show a commitment to pursue academics with the same ferocity. We celebrate the different talents that our students bring to the community,” says Professor King CHOW, Acting Dean of Students.
Life’s Second Chapter
Also a young phenom, Chow Hiu-Yau has been puzzled about her future life after professional sport.
“Anna SHCHERBAKOVA, the world champion and 2022 gold medalist, is only 17. If I were to challenge myself to higher heights, it is now, or never. At the same time, I want to plan ahead for myself — attending university while I compete is ideal,” says Hiu-Yau, who got accepted by HKUST as an engineering freshman via JUPAS last year.
“The Engineering School has offered me advice on course planning. All my lessons are arranged in two full days so I can use the rest of the week for training,” adds Hiu-Yau.
For the athletes who get in via other paths, the University is also ready to help.
Professor Emily NASON, Director of Undergraduate Recruitment and Admission, says the assistance would be as much personalized as it can be to suit the needs of each student athlete.
“Our team will get in touch with the athletes and their coaches to understand their needs. Our assistance includes a tailor-made class schedule that fits into their training schedule, course planning advice and in some cases, individual tutoring and personalized counseling services for athletes who represent Hong Kong in international competitions,” says Prof. Nason.
In addition, examination rescheduling and extending study periods can also be arranged if necessary. Student athletes may also receive tuition scholarships and living allowance of up to HK$42,100 and HK$55,000 respectively subject to requirements. Given all the assistance and offer, they need to meet the academic requirements like other students to earn their degrees.
Late, but never too late
“The delayed graduation offer has really eased my worries,” says Hiu-Yau. “It is said that a skater cannot leave the ring for more than three days, or else you will lose touch. I am not ready to give up on my touch just yet, but I am also not going to give up my interests in engineering down the road.”
For Minnie, she is eager to prove that she has as much to show in her work, just like she does on court.
“I still have a lot of gas left in the tank and expect myself to make the adjustments and give it all on the court after my injury is healed,” says Minnie. “But at the same time, I do not take the decision to go to university lightly, and I am committed to do as much work as I am asked at HKUST. I want to do well.”
Minnie adds that Physics is the discipline she would love to pursue. “Physics is what I would call a very intellectually challenging subject. I read a lot on Physics, and it helps me refine my table tennis skills, such as course prediction. Knowledge and education have done wonders for my mind.”
Prof. Chow certainly likes the determination that he sees from both, and the can-do spirit that is equally embraced by HKUST.
“Learning is always curiosity-driven at the university level,” Prof. Chow notes. “We want them to do well, both as an athlete and a student. I have no doubt that HKUST and our athletes will excel as a team.”
The Hong Kong University of Science and Technology (HKUST) has launched today WavyOcean - the first interactive marine environment visualization platform which offers an unprecedented level of data on the ocean in the Guangdong-Hong Kong-Macau Greater Bay Area (GBA), the entire China Seas1, and the Western Pacific Ocean. The platform will greatly facilitate marine research work and offer valuable data to policy makers on striking a balance between marine conservation and societal development, such as the Lantau Tomorrow Vision Plan.
Utilizing state-of-the-art oceanic numerical simulations, the platform not only visualizes oceanic processes, but also offers physical and biogeochemical data of the aforesaid oceans. Data available for download include environmental variables such as 3D ocean current, temperature, salinity, levels of nitrate, chlorophyll, dissolved oxygen; as well as atmospheric variables such as wind, temperature and pressure. Such comprehensive data sets offered on a one-stop-shop platform is set to provide a solid foundation to research topics such as marine hydrodynamics, hazards, pollutions, ecosystem and changing climate.
“Since the in-situ collection of oceanic data is logistically difficult and greatly limited in space and time, observational data in ocean science is scarce,” Prof. GAN Jianping, Chair Professor of the Department of Ocean Science and Department of Mathematics who led this research, said. “Therefore we have developed the China Sea Multi-scale Ocean Modeling System (CMOMS) and subsequently WavyOcean to cover the entire China Seas spatiotemporally. WavyOcean does not only couple ocean circulation with the ecosystem in the region, but can also present visual and interactive 3D spatiotemporal variations for the transport of oceanic energy and substances, biogeochemical properties and the nature of ecosystem. The platform itself is an innovative hub for research and ocean management while also being an informative source for the general public.”
WavyOcean is built on a decade of research works by Prof. Gan and his interdisciplinary team, with the support from the National Supercomputing Centers of Tianjin and Guangzhou. The WavyOcean project was supported by the Center for Ocean Research in Hong Kong and Macau (CORE), which was jointly established in 2019 by HKUST and the Qingdao Pilot National Laboratory for Marine Science and Technology, as well as Ocean-HK, a research project sponsored by the Theme-based Research Scheme under the University Grants Committee of Hong Kong since 2017.
“With our continuous enhancement of WavyOcean, policymakers and scientists will be able to better study and deploy marine resources, mitigate the impact of climate change and the potential effects that new policies such as the Lantau Tomorrow Vision may bring to the marine ecosystem,” Prof Gan said. “We hope the public can better understand the ocean at their fingertips, and become more aware on the significance in protecting the ocean.”
WavyOcean can be viewed on website or on mobile devices using the WavyOcean app.
Download the application here:
1South China Sea, East China Sea, Yellow Sea and Bohai
(This article was originally published on EurekAlert! on March 2, 2022)
Researchers at the Hong Kong University of Science and Technology (HKUST) and the University of Chicago (UChicago) have shown for the first time how to design the basic elements needed for logic operations using a kind of soft material called liquid crystal, paving the way for a completely novel way of performing computations with potential applications in robotics.
“We showed that you can create the elementary building blocks of a circuit—gates, amplifiers, and conductors—with liquid crystals, which means you should be able to assemble them into arrangements capable of performing more complex operations,” said Juan DE PABLO, the Liew Family Professor in Molecular Engineering at Pritzker School for Molecular Engineering, UChicago, senior scientist at Argonne National Laboratory, and the senior corresponding author on the paper. “It’s not often that you are able to see a new way to do computing and it’s a really exciting step for the field of active materials.”
The research aimed to take a closer look at the molecular order in liquid crystals, a soft material that is commonly used in making LCD TVs and laptop screens. The molecules in a liquid crystal tend to be elongated, and when packed together they adopt an orderly structure that can also shift around as a liquid does.
One consequence of this odd molecular order is that there are spots in all liquid crystals where the ordered regions bump up against each other and their orientations don’t quite match, creating what scientists call “topological defects.”
Scientists are intrigued by these defects, wondering if they could be used to carry information – similar to the functions that electrons serve in the circuits of our laptop or phone. But it’s proved very difficult to control their behavior. “Normally, if you look through a microscope at an experiment with an active liquid crystal, you would see complete chaos—defects shifting around all over the place,” said Prof. de Pablo.
But last year, an effort from Prof. de Pablo’s lab headed by Prof. ZHANG Rui, an assistant professor at Department of Physics, HKUST, then a postdoctoral scholar at the Pritzker School of Molecular Engineering, in collaboration with Prof. Margaret GARDEL’s lab from UChicago and Prof. Zev BRYANT’s lab from Stanford, figured out a set of techniques to control these topological defects.
They showed that if they controlled where they put energy into the liquid crystal by shining a light only on specific areas, they could guide the defects to move in specific directions. In a subsequent new paper, they took it a logical step further and determined that it should be theoretically possible to use these techniques to make a liquid crystal perform operations like a computer.
The results were published in Science Advances on February 23, 2022.
“These topological defects have many of the characteristics of electrons in a circuit—we can move them long distances, amplify them, and shut or open their transport as in a transistor gate, which means we could use them for relatively sophisticated operations,” added Prof. Zhang.
While the results are not likely to become transistors or computers right away, the technique could point the way towards devices with new functions in sensing, computing, and robotics, especially in the field of soft robotics. Using active liquid crystals, the team said it might be possible to create soft robots that can do some of their own “thinking”.
They can also imagine using topological defects to ferry small amounts of liquid or other materials from place to place inside tiny devices. “For example, perhaps one could perform functions inside a synthetic cell,” said Prof. Zhang. It’s possible that nature already uses similar mechanisms to transmit information or perform behaviors inside cells, he said.
The research team, which also includes co-author and UChicago postdoctoral researcher Ali MOZAFFARI, is working with collaborators to carry out experiments to confirm the theoretical findings.
This work used resources of the University of Chicago Materials Research Science and Engineering Center.
Table tennis Olympic medalist Minnie SOO Wai-Yam will be admitted to the School of Science at The Hong Kong University of Science and Technology (HKUST) in the new academic year (2022/23), following the introduction of a new admission scheme for elite athletes by the University Grants Committee (UGC) last week.
Minnie Soo, a bronze medal winner of the Table Tennis Women’s Team Competition in the Tokyo 2020 Olympic Games, is the first student admitted to the HKUST mainly based on her sports performance after UGC launched the new Student-Athlete Learning Support and Admission Scheme (SALSA).
To encourage students to develop non-academic talents such as sports, HKUST launched the Student Athletes Admissions Scheme (SAAS) three years ago to offer student athletes special admission arrangements, scholarships, living allowance, academic accommodations and other relevant assistance. There are currently around 15 elite athletes studying at HKUST.
To better support SALSA, the University enhanced SAAS to provide more flexible admission and assistance to top local athlete applicants. Apart from designated SAAS advisory committee, HKUST is set to recruit extra academic tutors to provide successful applicants with more flexible and personalized academic support. That includes extending their study periods, study load adjustment, examination rescheduling, and class attendance waiver. They may also receive tuition scholarship and living allowance of up to HK$42,100 and HK$55,000 per year respectively, along with sponsorships on sports competitions, injury prevention, treatment trainings and counselling services.
Minnie Soo, who will begin her life as a university student in September, said she was both excited and nervous. “It’s been a decade since I last studied on a campus. I chose to become a full-time athlete at an age when I should be studying at school, because there is a golden period for every athlete and I want my full potential unleashed. It has been a wonderful and rewarding journey, and now I will dedicate this passion to the second chapter of my life.”
Enrolled in the school-based science program, Minnie said she is interested in physical science and is aspired to become a scientist or educator in the future.
Prof. Emily NASON, Director of Undergraduate Recruitment and Admissions, said the University is delighted to admit a devoted and outstanding athlete like Minnie to join the HKUST community. “She never gives up on her studies despite a highly demanding training schedule, and overcomes painful injuries to score the victory. I truly admire her resilience, and see a great deal of resemblance to the can-do spirit at HKUST,” Prof Nason said. “The University will provide a holistic and supportive learning environment to these bright young athletes so they can pursue their academic dream while winning glory for Hong Kong.”
HKUST has re-opened SAAS to non-JUPAS applicants to allow more outstanding athletes to pursue their undergraduate studies in the 2022/23 academic year. Deadline for both JUPAS and Non-JUPAS athlete applicants are now March 31. Please visit the website of the scheme for more information.
The year was 1996, and HKUST had just been founded a few years ago. Tim LEUNG Shing-Yu, a freshman studying mathematics, was not quite sure what opportunities were lying ahead.
“I remember vividly I was overwhelmed by the sheer number of people on campus on my first day here. I had no idea what it was like to study at a university, let alone my future career. The only thing I knew for sure was my fascination for applied mathematics,” Prof. Leung, now Professor and Associate Dean of the School of Science at HKUST, recalls.
He had three years of engaging and dynamic university life during his undergraduate years and went on to complete an MPhil degree. When it was time to graduate, he was anxiously awaiting his job offer as a teacher, just as many of his classmates did.
“At the time, we all thought the only career for those who studied math would be teaching at a local secondary school. That basically would set a lot of people for life, and I was too waiting for my offer letter,” Prof. Leung said.
Luckily for Prof. Leung and HKUST, that offer letter did not arrive on time. Not before then-head of the Department of Mathematics, Prof. CHENG Siu-Yuen, spotted the young man’s talent and potential, and advised him to reconsider his options and pursue further graduate studies in the US.
“Prof. Cheng was adamant that I should apply for further graduate studies in the US,” Prof. Leung laughs. “Since overseas exchange was not common at the time, I had never been to anywhere during my undergraduate studies. So I told myself that I could treat it as my own belated exchange.”
As things turn out, a change of scenery was all a young and ambitious Tim needed to realize his enthusiasm for math. From 2001, Prof. Leung would spend the next eight years in the US, not only completing his PhD in math at UCLA, but also conducting three more years of post-doc work at UC Irvine. At one point, he thought he would never leave the US.
“When I completed my post-doc studies, I began to look for a full-time teaching position everywhere, but Prof. Cheng reached out again and asked whether I would be interested to work at HKUST,” Prof. Leung said. “I was not sure if I would ever be able to adjust to the life in Hong Kong again, especially after spending almost a decade in California; but how could I say no to my alma mater? And so I came home.”
More than just teaching math
Since returning to HKUST in 2009, Prof. Leung has always been looking for new challenges in teaching, mentoring, course-building, and of course, his own research. At the same time, he remains methodological in his approach—there would be no fancy powerpoint slides in his math lectures, only the good old whiteboard and note-taking.
“The way I conduct my classes is kind of old school but works well for math students,” Prof. Leung smiles. “This is how I go through with my students together: pull out the whiteboard, solve problems, do the coursework, mid-terms, and finals, rinse and repeat. Only by then, I believe, would one be able to claim the knowledge we teach in class his own. This is how we learn math. You get ahold of the basics, and we go from there.”
With the switch from a three-year to a four-year undergraduate system since 2009, a new emphasis has been put on broadening the horizons of undergraduates with minors and cross-disciplinary selective courses—a new challenge that he has embraced with both arms.
“Today, our emphasis is to get students to show initiative and learn on their own at an early stage,” Prof. Leung noted. “Our UROP program, for example, would be really challenging for my generation, where undergraduate students would be asked to conduct research on their own. But now? I am often surprised by the results and vigor shown by students I mentor in the program. They have learned much by taking classes in other disciplines, which probably stimulated their response to take initiatives in their own pursuit.”
UROP, the Undergraduate Research Opportunities Program, is a signature program of HKUST that provides early hands-on research experience to undergraduate students since its launch in 2005.
“I am very pleased to see the results and different career paths developed by some of the brightest students I have had mentored via UROP over the years,” Prof. Leung notes. “My first research student is now an assistant professor at HKBU, and he showed a lot of potential when he did UROP and then MPhil with me, where he would go on and win a Croucher Scholarship to pursue his PhD at the University of Oxford.”
The joy of nurturing math talent
And increasingly, the academia is no longer the only path math majors would pursue. Nurturing pillars of society is sure to be the most rewarding part of his career at HKUST.
“While I am proud to see some of my students land teaching and faculty positions in other universities in Hong Kong, I am also glad that many students take off their careers across a multitude of industries like IT, business, finance, and even running a start-up,” Prof. Leung says.
“Other PhD students, whom I have invited to share their career stories recently, have also led successful careers in investment banking and cryptocurrency,” Prof. Leung continues. “Did I teach them how to invest? Of course not. The fact is the skills they gained from vigorous training in applied math is transferrable. The sense of interpreting numbers, deciding strategies and algorithms can be applied in many industries. Employers are discovering that talented young minds with a solid foundation in math can easily adapt to different working environments and job duties.”
“I am now mentoring six graduate students, four at the MPhil and two at the PhD level, which is the largest group of students I have had since I joined HKUST,” Prof. Leung says. “From my earlier teaching days to now, I realized that my job is not only to teach knowledge, but I also have to put myself into students’ shoes and help them to understand the materials better,” adds Prof. Leung. In recent years, Prof. Leung has taken more new challenges in strides, from taking part actively in student recruitment to organizing the renowned Hang Lung Mathematics Award, in which he finds such diversity in working duties to be a joy and keeps his mind occupied in a variety.
To stir interest in STEM education and share his passion for math and science, Prof. Leung is also running his personal blog and YouTube channel, mixing in ways and approaches where younger students would find easy access to him. Teaching, indeed, is not limited to the conventional classroom setting.
“When I was young, I was probably wrong to think that I had only a limited set of options,” Prof. Leung says. “Now, we want to make sure everyone knows that the sky is the limit, no matter what you study. Put in the work, and expect the best.”
(This article was originally published on EurekAlert! on February 24, 2022)
A research team led by LIFS Assoc. Prof. Tom CHEUNG has discovered the constructive role of a protein in driving the skeletal muscle stem cell activation to repair muscle following damage, laying the foundation for further study in the mechanisms of stem cell quiescence-to-activation transition and stem cell-based muscle regeneration.
Skeletal muscle stem cells, or satellite cells (SCs), are indispensable for repairing damaged muscle and are key targets for treating muscle diseases. In healthy uninjured muscle, these reserve stem cells lie in quiescence, a dormant state, to maintain the resident stem cell pool for future muscle repair. When muscle damage occurs, these quiescent muscle stem cells will quickly “wake up”, generating enough muscle progenitor cells to build new muscle.
Despite being a critical step in muscle regeneration, the muscle stem cell quiescence-to-activation transition remains an elusive process, and scientists’ understanding of its mechanism and the true quiescent SC proteomics signature – the information about the entire set of proteins – has been limited.
Recently, using a whole mouse perfusion technique developed in its own laboratory to obtain the true quiescent SCs for low-input mass spectrometry analysis, a team of scientists at the HKUST revealed that a regulating protein called CPEB1 is instrumental in reprogramming the translational landscape in SCs, hence driving the cells into activation and proliferation.
“In our study, we found discordance between the SC proteome and transcriptome during its activation, revealing the presence of a post-transcriptional regulation,” said Prof. Tom CHEUNG, lead researcher of the team and S H Ho Associate Professor of Life Science at HKUST. “Our analysis shows that levels of CPEB1 protein are low in quiescent SCs, but upregulated in activated SCs, with loss of CPEB1 delaying SC activation.”
In their subsequent RNA immunoprecipitation sequencing analysis and CPEB1-knockdown proteomic analysis, the researchers found that CPEB1 phosphorylation regulates the expression of the crucial myogenic factor MyoD – a protein involving in skeletal muscle development – by targeting some of the sequences found within the three prime untranslated region (3'UTR) of the target RNA transcript to drive SC activation.
Their findings were recently published online in the journal Nature Communications on February 17, 2022.
“It means that the manipulation of CPEB1 levels or phosphorylation can increase SC proliferation to generate enough myogenic progenitor cells for muscle repair, which could be a potential therapeutic target for muscle repair in the elderly,” noted Prof. Cheung, adding that the findings will play a fundamental role in the field as scientists continue to probe more comprehensively the mechanisms of stem cell quiescence exit and stem cell-based tissue repair.
The next step of the team’s research will involve assessing muscle regeneration in vivo in CPEB1-knockout mice to further strengthen the role of CPEB1 in SC-mediated muscle regeneration. “Furthermore, using high throughput screening, we can discover compounds that can upregulate CPEB1 protein expression to boost muscle regeneration,” Prof. Cheung said.
Since its establishment 30 years ago, HKUST has been cultivating an inclusive learning and research environment where every student, researcher, and faculty members are encouraged and empowered to excel regardless of gender and background. In part one of this Smashing the Glass Ceiling series, we are bringing you tips from HKUST female members on how to break invisible barriers and get ahead to reach their full potential.
STEM is a field that is traditionally perceived as being male-dominated. In a gender-friendly community like HKUST, we are not short of female role models to provide reassurance and inspirations for younger females who want to pursue ambition in STEM. Here some of our female faculty members share with us their career stories and the revolutionizing potential of their research work.
Don’t give in to gender favoritism.
IM Eun Soon, Assistant Professor in the Department of Civil and Environmental Engineering was a civil servant at the National Institute of Meteorological Research in Korea before she joined HKUST. Prof. Im says she didn’t get to the position at first and gender barriers were one of the obstacles.
“I was still working on my PhD and not fully qualified then, and there was gender bias in the hiring process. Regardless of the reason, I didn’t give up. I worked there for a temporary position and demonstrated my latent potential and work ethics. After six months, I secured a permanent position.”
Prof. Im’s research at HKUST focuses on one of the biggest issues of the age––climate change. She has been working on the development and improvement of climate models for Southern China, including Hong Kong, to determine the ramifications of climate change induced by anthropogenic forcing such as greenhouse gases and land-use change.
Prof. Im says there continues to be a big fall-off rate among women in the STEM field. “About 50 per cent of my classmates were female when I was an undergraduate. However, that ratio sharply decreased as I moved up the ranks. As of now, only a few female classmates have survived in this field and held major related jobs.” But she advises young women not to get despondent, “I genuinely believe there is no singular clear-cut path for long-term success.”
My mentors believed in me and encouraged me.
The power of believing in yourself is also a force that motivates Charmaine YUNG, Assistant Professor in the Department of Ocean Science, who is herself a product of the University, studying biology as an undergraduate, before completing a PhD at Duke University in the United States.
Her research interests lie in viral ecology and biological oceanography. Her study about picoeukaryotes around Hong Kong waters will provide insights to how the organisms respond to climate change and help establish model systems for advanced studies.
“Being a woman has not hindered me at all. My mentors, Dr. Dana HUNT, and Prof. Alexandra WORDEN, were great role models as successful female ocean scientists. They believed in my ability and encouraged me throughout my research journey. They also helped me build invaluable professional networks,” says Prof. Yung.
Mentorship has also proven rewarding for WANG Yiwen, Assistant Professor in the Department of Electronic and Computer Engineering, who has been at HKUST since 2017. She has mentored a number of female students, one of whom won second place in the Best Student Paper Award in the Workshop on Brain-Machine Interface (BMI) Systems at the flagship annual conference of the IEEE Systems, Man, and Cybernetics Society. Prof. Wang has been working on the development of Brain Machine Interfaces, which aims to build engineering approaches to diagnose the impairment and restore the cognitive functions for the disabled, such as memory loss, motor paralysis and attention deficit.
Don't be afraid to join STEM and be prepared for challenges.
Angela WU Ruohao, Assistant Professor in the Division of Life Science and Department of Chemical and Biological Engineering, works with her research group on a new technology for sequencing single-cells called scONE-seq, which will help observe tumours at various stages and thus better understand cancer and help generate new therapeutic strategies. The field especially embodies a cross-disciplinary ethos.
“Students working on the projects have to develop both engineering skills and deep biological knowledge such as cancer biology and neurobiology,” says Prof. Wu, also a passionate mentor herself. “I find mentoring and nurturing future scientists very fulfilling. There are many barriers for women in the field that are too numerous to name. But for me, I keep in mind my genuine interest and passion and disregard the barriers. If more women can persist, we will head toward a better future.”
While she encourages younger women scientists to be brave and reach for their ambitions, Prof. Wu advises them to be prepared for challenges. “I think women who are interested in STEM, love the feeling of discovery and love learning about the world around us, or love to create in the STEM field, should not be afraid to join our ranks. Girls and women in STEM should be aware of these barriers, and that it may be very difficult at times.”
Beware of unconscious and systematic inequity.
LI Jiying, Assistant Professor in the Department of Ocean Science, agrees that sometimes the systemic inequity is so prevalent that women don’t see the barriers.
“I observe that women are expected to take on more responsibility for their family and are appreciated less when they are successful in their careers. The expectations of society and a lack of role models discourages women from persevering at what they love to do,” she says. "I always stay vigilant to such misconceptions and feel less intimidated."
Prof. Li is dedicated to solving regional environmental problems and raising awareness of water quality issues in Hong Kong. She studies the effect of geochemistry affecting microbial metabolism and ecology in water systems.
Stay true to your passion.
An HKUST trailblazer in a field where there have historically been few women is Rhea LIEM, Assistant Professor, Department of Mechanical and Aerospace Engineering, has recently been recognized with the University Grants Committee Teaching Award for her outstanding teaching performance. Raised by parents who practised no bias in gender roles and educated in schools that had a similar outlook, Prof. Liem passes the same values to her students. “I always encourage all my students, regardless of their genders, to find their true identity, stay true to their passion and disregard barriers and general perceptions.”
These faculty members are testimony to a rise in women working at the highest levels of STEM fields. Their research projects were supported by the Chau Hoi Shuen Foundation, which donated $10m to the University in 2019 with the aim of increasing the visibility of women in the STEM research field and supporting tenure-track women faculty whose research has the potential to influence industries and adopts cross-disciplinary approaches.
Also benefiting from the Foundation’s support are Julie SEMMELHACK, Assistant Professor in the Life Science Division, and Becky KUANG Yi, Assistant Professor in the Department of Chemical and Biological Engineering. Prof. Semmelhack’s lab uses functional imaging and quantitative analysis of behaviour to understand the neural circuits involved in visual behaviour, while Prof. Kuang is currently conducting research to develop a synthetic RNA and a synthetic peptide-based platform for multiplex non-invasive purification of cells, ultimately to be used in multiple laboratory and clinical applications.
At HKUST, students and faculty members are encouraged to pursue advanced learning and knowledge through research and teaching in an equitable environment that the University endeavors to build. This is facilitated by a number of initiatives, including the WISE Scholarship, which encourages high-calibre female students to join our School of Science, School of Engineering and Interdisciplinary Programs Office. Besides, the Women Faculty Association and the IWDxHKUST are both devoted to promoting gender inclusiveness and equality.
HKUST has always been a female-friendly space where abundant resources and opportunities are available for women who consider a future in STEM. Our doors are widely open to talents regardless of background and gender.
(This article was originally published on EurekAlert! on January 28, 2022)
A joint research team from the Hong Kong University of Science and Technology (HKUST) and the University of Tokyo discovered an unusual topological aspect of sodium chloride, commonly known as table salt, which will not only facilitate the understanding of the mechanism behind salt’s dissolution and formation, but may also pave the way for the future design of nanoscale conducting quantum wires.
There is a whole variety of advanced materials in our daily life, many gadgets and technology are created through the assembly of different materials. Cellphone, for example, adopted a combination of many different substances — glass for the monitor, aluminum alloy for the frame, and metals like gold, silver and copper for its internal wirings. But nature has its own genius way of ‘cooking’ different properties into one wonder material, or what is known as ‘topological material’.
Topology, as a mathematical concept, studies what aspects of an object are robust under a smooth deformation. For instance, we can squeeze, stretch, or twist a T-shirt, but the number its openings would still remain as four so long as we do not tear it apart. The discovery of topological phases of matter, highlighted by the 2016 Nobel Prize in Physics, suggests that certain quantum materials are inherently a combination of electrical insulator and conductor. This could necessitate a conducting boundary even when the bulk of the material is insulating. Such materials are neither classified as a metal nor an insulator, but a natural assembly of the two.
While the topological qualities of materials attract a lot of research interests, at present they are only realized in an exclusive set of exotic materials - such as the two-dimensional graphene. However, in a recent work, Prof. Adrian PO Hoi Chun, Assistant Professor from HKUST’s Department of Physics and his collaborator, Prof. Haruki WATANABE from the University of Tokyo, have discovered a surprising connection between topology and a large class of ordinary substances, including table salt.
Table salt, or sodium chloride, is one of the most common crystals frequently featured in high-school chemistry textbooks as a prototypical ionic compound. It’s long believed that such well-known substance are topologically boring. However, the research team discovered that table salt can actually, in theory, realize a form of recently introduced, “higher-order” topology. Instead of conducting two-dimensional surfaces or one-dimensional edges, the zero-dimensional corner of a grain of salt showcases an anomalous behavior in which electric charges are effectively fractionalized into one-eighth of the fundamental unit of Nature. Furthermore, the robustness of this topological property implies that even if the chemical structure is modified into other formats such as silver chloride or potassium fluoride, the result would still be upheld.
Prof. Watanabe said the connection between topological materials and everyday substances like table salt is totally unexpected. Prof. Po said the result suggests an overlooked aspect of topology in common ionic compounds. “The finding may inspire future design of nanoscale conducting quantum wires, or novel drug delivery method, which is so often studied along with the salt dissolution processes,” Prof. Po said, adding that “it is amusing to realize how we ingest fractions of an electron upon our every meal.”
The work was published on the Physical Review X.
(This article was originally published on EurekAlert! on January 24, 2022)
Researchers at the Hong Kong University of Science and Technology (HKUST) have demonstrated a new way to control the quantum state through the loss of particles – a process that is usually avoided in the quantum device, offering a new way towards the realization of unprecedented quantum states.
Manipulating a quantum system requires a subtle control of quantum state with zero imperfect operations, otherwise the useful information encoded in the quantum states is scrambled. One of the most common detrimental processes is the loss of particles that consist of the system. This issue has long been seen as an enemy of quantum control and was avoided through the isolation of the system. But now, researchers at the HKUST have discovered a way that could gain quantum control from loss in an atomic quantum system.
The finding was published today in Nature Physics.
Prof. Gyu-Boong JO, lead researcher of the study and Hari Harilela Associate Professor of Physics at HKUST, said the result demonstrated loss as a potential knob for the quantum control.
“The textbook taught us that in quantum mechanics, the system of interest will not suffer from a loss of particles as it is well isolated from the environment,” said Prof. Jo. “However, an open system – ranging from classical to quantum ones, is ubiquitous. Such open systems, effectively described by non-Hermitian physics, exhibit various counter-intuitive phenomena that cannot be observed in the Hermitian system.”
The idea of non-Hermitian physics with loss has been actively examined in classical systems, but such counter-intuitive phenomena were only recently realised and observed in genuine quantum systems. In the study, HKUST researchers adjusted the systems’ parameters such that they sweep out a closed loop around a special point – also known as an exceptional point occurring in the non-Hermitian system. It was discovered that the direction of the loop (i.e. whether it goes clockwise or anti-clockwise) determines the final quantum state.
Jensen LI, Professor of Physics at HKUST and the other leader of the team, said, “This chiral behavior of a directional quantum state transferring around an exceptional point can be an important ingredient in quantum control. We are at the starting point in controlling non-Hermitian quantum systems.”
Another implication of the findings is how two seemingly unrelated mechanisms: non-Hermitian physics (induced by loss) and spin-orbit coupling, interplay. Spin-orbit coupling (SOC) is an essential mechanism behind intriguing quantum phenomena such as topological insulator, which behaves as an insulator in its interior but whose surface flow electrons act like a conductor.
Despite the major advances in non-Hermitian physics, an SOC mechanism is only widely studied in Hermitian systems, much less is known experimentally on the major role played by the loss in spin-orbit-coupled quantum systems. The better understanding of such non-Hermitian SOC is of paramount importance to the development of novel materials, but it remains elusive in the area of condensed matter physics.
In this work however, researchers realized for the first time a dissipative spin-orbit-coupled system for ultracold atoms, fully characterizing its quantum state and demonstrating chiral quantum control in the context of non-Hermitian physics. This finding sets the stage for future exploration of spin-orbit coupling physics in the non-Hermitian regime, and highlights the remarkable capabilities of non-Hermitian quantum systems to realize, characterize, and harness two fundamental mechanisms, namely loss and SOC, providing a new approach for precisely simulating such competing mechanisms in a highly controllable quantum simulator with ultracold atoms.
The research was funded by the Research Grants Council of Hong Kong, the Croucher Foundation, and Harilela Foundation.
(This article was originally published on EurekAlert! on December 1, 2021)
Researchers from The Hong Kong University of Science and Technology (HKUST) and Hong Kong Baptist University (HKBU) have decoded for the first time the demographic history, genetic structure, and population connectivity of a deep-sea limpet widely distributed in vent and seep ecosystems in the Northwest Pacific. This study not only enhances our knowledge of the historical population divergence and contemporary gene flow of deep-sea organisms under the intricate interactions amongst local habitats, seafloor topography, and ocean currents, but also serves as a scientific basis for better conservation of marine biodiversity and more effective environmental management.
The discoveries of deep-sea hydrothermal vents in the late 1970s and hydrocarbon seeps in the early 1980s have significantly changed our understanding of how life has evolved on Earth. Unlike shallow-water ecosystems that are mainly driven by photosynthesis, deep-sea vent and seep ecosystems – characterized by darkness, high pressure, and often high concentrations of toxic substances - are primarily supported by chemosynthesis. Distributed in tectonically active areas and along continental margins, these ecosystems form “life oasis” in the deep ocean and harbor a diverse amount of creatures. Neighboring vent fields and seep areas are usually separated by tens to hundreds of kilometers. Nonetheless, a number of species have been found thriving in both habitats, raising intriguing questions on how their populations achieve connectivity between widely separated habitats and whether differences in habitat types facilitate intraspecific divergence.
Now, a research team led by Prof. QIAN Peiyuan, Head and Chair Professor of HKUST’s Department of Ocean Science and Prof. QIU Jianwen, Professor of HKBU’s Department of Biology, has collaborated with marine scientists from Ocean University of China and Japan Agency for Marine-Earth Science and Technology (JAMSTEC) to study the demographic history, genetic structure, and population connectivity of a deep-sea limpet widely distributed in vent and seep ecosystems in the Northwest Pacific.
With the application of population genomics analyses, the team for the first time unveiled four distinct habitat-linked genetic groups of deep-sea limpets in the Northwest Pacific - one in vent and three in seep ecosystems. Demographic analyses further revealed how the limpets’ migration events have contributed to the formation of these four genetic groups. Historically, the deep-sea limpet has diversified into two seep genetic groups, with the first seep genetic group inhabiting the shallower seep area in the Kuroshima Knoll. A few limpet larvae from which then invaded into the Okinawa Trough possibly along with the historical shifting of the Kuroshio Current, adapted to the vent habitats within the trough region, and eventually formed the Okinawa Trough vent genetic group. Meanwhile, the second seep genetic group inhabiting the deeper seep areas recently diverged into two distinct seep genetic groups in the Jiaolong Ridge of the South China Sea and the Sagami Bay. Such a pattern of genetic divergence may have been associated with the barrier effect of the Luzon Strait and the reduced methane supply of the Jiaolong Ridge seep in the South China Sea over the last two thousand years.
The team has also analyzed the physical ocean modeling data to illustrate the potential roles of seafloor topography and ocean currents in shaping the genetic connectivity, contemporary migration, and local hybridization of the deep-sea limpets. Particularly, numerical particle release experiments demonstrated that water transport between the Okinawa Trough and the open Northwest Pacific was topographically constrained (especially at and below 800 m depth), which helps to explain the high level of population connectivity and genetic homogeneity of limpet populations that colonize the vent fields in the Okinawa Trough. Numerical particle release experiments also inferred that transport of the North Pacific Intermediate Water may have facilitated the contemporary dispersal of a few limpet larvae from the Sagami Bay seep into the Okinawa Trough vents, and thereafter accounted for the hybridization between individuals belonging to these two genetic groups.
This study has enhanced our knowledge of the historical population divergence and contemporary gene flow of deep-sea organisms inhabiting hydrothermal vents and hydrocarbon seeps under the intricate interactions amongst local habitats, seafloor topography, and ocean currents. “Population connectivity is a critical criterion in assessing the biodiversity conservation value of any particular habitat as stipulated by Convention on Biological Diversity (CBD), International Maritime Organization (IMO) and other United Nations (UN) agencies, along with various international organizations. Therefore, we anticipate the results of this study will deepen our understanding of the demographical mechanisms and population connectivity of deep-sea organisms, lay a foundation for the conservation of marine biodiversity and sustainable utilization of marine resources, and pave the way for the establishment of regional environmental management plans as well as the designation of marine protected areas in global ocean,” said Prof. QIAN, also David von Hansemann Professor of Science.
The research findings were recently published in the international academic journal Molecular Biology and Evolution.
(This article was originally published on EurekAlert! on September 7, 2021)
Scientists from The Hong Kong University of Science and Technology (HKUST) and The Hong Kong Polytechnic University (PolyU) have developed an in-vitro vesicle formation assay, shedding light on cargo clients and factors that mediate vesicular trafficking and providing a robust tool to offer novel insights into the secretory pathway.
The secretory pathway is a very important process that takes place in human cells. Many growth factors, hormones and other important factors in the human body are secreted from cells through the secretory pathway to perform their physiological functions. In addition, many newly synthesized proteins must be transported to specific subcellular localization through the secretory pathways to perform their functions. In the secretory transport pathway, transport vesicles function as vehicles to carry cargo molecules. Similar to logistics and delivery services in our daily lives, the transportation of cargo molecules to the correct target sites depends on whether the cargo molecules are accurately sorted into specific transport vesicles. Defects in cargo sorting would induce defects in establishing cell polarity, immunity, as well as other physiological processes.
The key players that mediate protein sorting in the secretory pathway include small GTPases of the Arf family and cargo adaptors. The Arf family GTPases cycle between a GDP-bound inactive state and a GTP-bound active state. Upon GTP binding, Arf proteins mediate membrane recruitment of various cytosolic cargo adaptors. Once recruited onto the membranes, these cargo adaptors recognize sorting motifs on the cargo proteins to package cargo proteins into vesicles.
Although significant progress has been achieved in understanding the general steps of cargo sorting, the spectrum of cargo clients of a specific Arf family member or cargo adaptors remains largely unexplored. Led by Prof. GUO Yusong, Associate Professor of Division of Life Science at HKUST and Prof. YAO Zhongping from PolyU, the research team used an in-vitro assay that reconstitutes packaging of human cargo proteins into vesicles to quantify cargo capture. Quantitative mass spectrometry analyses of the isolated vesicles revealed cytosolic proteins that are associated with vesicle membranes in a GTP-dependent manner. One of them, FAM84B interacts with cargo adaptors and regulates transport of transmembrane cargo proteins. In addition, they uncovered novel cargo proteins that depend on GTP hydrolysis to be captured into vesicles.
Then they utilized this assay and identified cytosolic proteins that depend on a specific Arf family protein, SAR1A, to be recruited to vesicle membranes. One of the cytosolic protein, PRRC1, is recruited to endoplasmic reticulum (ER) exit sites, and interacts with the inner COPII coat. Its absence increases membrane association of COPII and affects ER-to-Golgi trafficking.
Utilizing this assay, they also identified the clients of COPII vesicles. These clients include two cargo receptors, SURF4 and ERGIC53. Through analyzing the protein composition of vesicles isolated from control cells or cells depleted of SURF4 or ERGIC53, they revealed specific clients of each of these two cargo receptors.
These results indicate that the vesicle formation assay in combination with quantitative mass spectrometry analysis is a robust and powerful tool to systematically reveal cargo proteins that depend on a specific factor to be packaged into vesicles, to analyze protein profiling of transport vesicles under different physiological conditions, and to uncover cytosolic proteins that interact with a specific factor on vesicle membranes.
This study was recently published in Proceedings of the National Academy of Sciences.
Prof. Guo’s research team focuses on investigating molecular mechanisms regulating protein sorting in the secretory pathway. Dr. HUANG Yan (a postdoctoral research associate from Prof. Guo’s lab at HKUST), Dr. YIN Haidi from PolyU and Dr. LI Baiying from CUHK are co-first authors of this study. Mr. LIU Yang, Dr. TANG Xiao, Miss WANG Wo and Miss WU Zhixiao from the Guo lab also participated in this study.