Pathway to Independence – an interview with Priti Agarwal

When did you first become interested in science?

Biology has been one of my favourite subjects since my early school days. However, I didn't get much hands-on research experience during my undergraduate studies. It was during my Master's, when I did internships in several research institutes, that I got my first exposure to the scientific process of discovery. It was eye-opening to see how the concepts we read about in textbooks were actually uncovered through research. I also learned that science is a constantly evolving field, not set in stone. This exposure made me think about how I could be involved in it. So, I decided to pursue a doctoral degree and applied to several institutes in India. I was selected at the Indian Institute of Technology, Kanpur (IITK), where I joined Prof. Kuppuswamy Subramaniam's lab. He's a developmental biologist who uses the nematode Caenorhabditis elegans as a model system to understand how organs and organisms grow and develop. As I delved into my research, the joy of small successes and the stimulating conversations with passionate researchers and colleagues excited me beyond measure. It was then I realised that academic research is the long-term career choice for me. So, you could say that my interest in science was a nurtured one, but during my PhD, I became inherently captivated by the different aspects of developmental biology, and I look forward to contributing to this ever-expanding field of science.

Why did you decide to join Kuppuswamy Subramaniam's lab?

At IITK, we didn't have those rotation projects you often hear about. Instead, we had a handful of labs with open PhD positions, and we were given a choice to select one of them. Prof. K. Subramaniam is a devoted and amazing teacher, and he delivered this captivating presentation about how a single cell transforms into a whole organism. He used C. elegans, as a model system, and I didn't really have a strong preference for any specific model organism back then, but his presentation was so engaging that it clicked for me. I knew right then what I wanted to do in the future.

Can you tell me about what you worked on during that time?

My graduate research focused on exploring the mechanism that regulates the self-renewal and differentiation decisions of stem cells. Maintaining a precise balance between self-renewal and differentiation is crucial for tissue homeostasis. Any disruption in this balance can be deleterious. Excessive proliferation at the expense of differentiation can lead to tumour formation, whereas differentiation without self-renewal can deplete the stem cell population, ultimately resulting in tissue degeneration. I studied this process in the case of germline stem cells (GSCs) in C. elegans. GSCs are adult stem cells that can either undergo mitotic division to replenish their population or enter meiosis to differentiate into gametes (eggs and sperm). I found that a highly conserved RNA-binding protein from the PUF family, known as PUF-8, functions redundantly with another RNA-binding protein called GLD-1 to promote the meiotic progression of male germ cells. In cases where both of these proteins are absent, male germ cells fail to complete meiosis; instead, they dedifferentiate into germ cell tumours (Agarwal and Subramaniam, 2015).

How did you decide what to do for your postdoc?

After my PhD, I wanted to transition to a new field but still relevant to developmental biology, and I came across an advertisement from my current postdoc supervisor, Prof. Ronen Zaidel-Bar, at the Mechanobiology Institute (MBI), NUS, in Singapore. I applied for the job, but he got back to me saying that he had already hired someone. However, he was really interested in my application and asked if I'd like to explore something different: the mechanics of the C. elegans gonad (although his lab was not focused on working on gonad at all, he used C. elegans embryos as the main model system). While several signalling pathways regulating germ cell development had been identified, the physical basis of its germline architecture and functionality remained largely unknown. I therefore got interested in this gap of knowledge and embarked on my postdoctoral projects, focused on understanding the mechanobiological aspects of C. elegans gonad development. Being trained as a classical geneticist and developmental biologist, I was very excited to transition from a gene-centric to a more holistic approach to understanding development, taking into consideration biophysical aspects of cells and tissues.

In my first project at MBI, I discovered a previously unrecognised tissue-scale cytoskeletal network present within the gonad. This cytoskeletal network is enriched in actomyosin regulators that function as an internal corset to maintain three-dimensional germline structure. Combining live imaging with laser-based, genetic and pharmacological manipulations, I found that the actomyosin corset is under constitutive tension. Using a qualitative mathematical model, I mapped the balance of forces and demonstrated how changes in the contractile forces at the corset affect the syncytial architecture of the germline (Agarwal et al., 2018). Recently, in a paper on which I was co-first author, we also found that an actin capping protein, CAP-1, regulates the contractility of this actomyosin corset to maintain reproductive tissue architecture (Ray et al., 2023).

In my second project at Tel Aviv University, we provided a novel mechanistic insight into organ morphogenesis. We found that directed cell invasion assisted by proliferative pressure and matrix degradation leads to gonad elongation, while an asymmetric leader cell-extracellular matrix adhesion creates torque that drives U-turning of the gonad. I believe that a similar mechanism may also be relevant for other developmental systems as well as solid tumour metastasis (Agarwal et al., 2022).

What was it like for you to move from India to Singapore, and then to Israel?

Despite cultural differences, my experiences in both Singapore and Israel were pleasant. Singapore's well-organised system made administrative tasks like visa processing and opening a bank account hassle-free. It has a nice transportation system, which made daily life easy, and I was fortunate to find a kind landlady for the three years that I was there. Scientifically, I was part of the MBI. This place was a goldmine for me as I was transitioning into a new field. At MBI, various research groups focused on different systems, but they all shared a common theme – understanding the role of mechanical forces. This was incredible for my learning curve because, with everyone working on the same topic, I quickly grasped the subject by attending seminars and engaging in discussions. Moreover, the institute has an advanced imaging facility, where I gained substantial knowledge about imaging techniques. What made this experience even more enriching was the open lab culture. The proximity of colleagues allowed me to quickly establish connections, share my research, troubleshoot problems and exchange reagents. All in all, it was a rewarding experience.

Moving from Singapore to Israel was quite the shift. Here in Israel, people are outgoing and friendly, always ready to lend a hand. One thing that made my transition smoother was staying with the same lab so, work-wise, it felt like a soft landing. Moreover, I got University dorms, so I didn't have to stress about finding a place to live. The food is delicious, especially for vegetarians like me – plenty of options. Israel has a very strong scientific culture. Tel Aviv University has several labs in the life sciences and medicine department with excellent facilities. Also, Israel is a small country, so it is not difficult to go to any University and get whatever help you need. For example, I teamed up with biophysicist Tom Shemesh at the Technion Institute for theoretical modelling. Another perk of being in Israel is its proximity to European countries, which allowed me to collaborate with a lab at ETH Zurich in Switzerland. Overall, my time in Israel has been a nice experience. Moving between countries teaches you to adapt to different situations and learn valuable lessons, although it can be a bit trickier if you have a family.

How did you hear about the Pathway to Independence Programme and why did you decide to apply?

The first time I came across this opportunity was on ‘the Node’ website. Given my aspiration to become an Independent Researcher, applying for this programme felt like a logical step. I realised that this programme would not only enhance my CV and profile but also elevate my visibility within the field of cell and developmental biology. Furthermore, this programme offered mentorship for job market navigation, feedback on my research proposal, cover letter and job talk. I extend my sincere gratitude to Prof. Swathi Arur, my mentor through this programme. Swathi reviewed my application and job talk, and offered valuable suggestions. Also, this programme provides an opportunity to network with other PI fellows. Connecting with fellow professionals in the field might lead to research collaborations and being a part of a supportive peer group would be a valuable resource for seeking advice and troubleshooting future challenges. In addition, this programme offers training on leadership, managing a lab, recruiting students and handling administrative tasks.

Where would you like to start your lab?

When it comes to starting my lab, the location isn't the top priority for me. What really matters is finding an institute that offers excellent infrastructure, especially when it comes to microscopy, as my work relies heavily on it. In addition, I am looking for a place that traditionally has strength in developmental biology because it opens up several opportunities: First, I can get critical feedback and suggestions from the experts in the field on my grant applications, research ideas and outputs. Second, it could foster new collaborations with the people using different model system, which I am particularly interested in. And third, it ensures I stay up to date with the latest developments in both technology and perspectives in the field. Lastly, I would like to join a place that offers good support and mentorship for early career researchers.

What do you find most exciting about starting your own group?

What excites me is the chance to work on questions that interest me the most. Obviously, this a cliché, but being independent would give me more room to explore my own innovative ideas which might be risky. Although, there are fair chances of failure, embracing failure is an inherent part of the scientific process. I believe that taking calculated risks and experimenting with novel concepts are essential aspects of being a scientist. Also, as my own research career has been nurtured by different mentors, it gives me an opportunity to mentor the next generation and I hope that many of them will become much better scientists than me.

Do you think mentorship is crucial for a research career?

No doubt mentorship is the most important thing for anyone's career. Whatever I am today is because of my mentors – I would not be here without them. Mentors have different styles: my PhD supervisor taught me how to be scientifically rigorous and disciplined, how to maintain my lab notebooks, give a good presentation and write a research paper, while Ronen gave me much more freedom to work on my own research projects. He actively encourages students to apply new techniques and tools to their research questions. He has been immensely supportive throughout my postdoctoral period and even at this crucial stage of my career transition.

What do you think will be the biggest challenge of becoming a PI and how will you go about preparing for it?

The most challenging part of being a PI is taking on the responsibilities of graduate students and Postdocs. Research projects can be risky, time-consuming and full of uncertainties. Graduate students typically have 4-5 years for their PhD programmes, and they must achieve meaningful milestones in that time. Thus, to keep the trust students and fellows will place on me for their academic career aspirations would be the biggest challenge. Also, I will have to meet the expectations of the University/Institute and funders who would provide vital support for my research. Both will require diligent effort on my part. To prepare for these challenges, I plan to take a proactive approach. I will thoroughly evaluate and refine my research ideas before presenting them to my students, ensuring they are well-considered and viable. I'll also encourage the development of backup projects without overwhelming them with work and offer hands-on assistance in the lab when needed. Furthermore, I am committed to nurturing the comprehensive growth of these aspiring scientists, which will involve promoting their engagement in conferences and facilitating visits to other labs for learning new skills and collaborations.

What research questions would you like to address in your lab?

The long-term goal of my lab research would be to decipher how biochemical and mechanical signals coordinate at the cell and tissue level to sculpt an organ with unique architecture and functionality. I will be using C. elegans as the model system with my primary focus on gonad development. The C. elegans gonad is a well-established model for studying organogenesis involving several biological processes such as cell invasion, stem cell proliferation, differentiation, gametogenesis and fertilisation. Given the high conservation of these processes across species in development and disease, I believe my research focused on understanding the biomechanics of the C. elegans gonad will not only reveal how organs form and function but might also provide insight into the causes of developmental anomalies, cancerous outgrowth and sterility. More specifically we will be asking: what is the role of mechanical force in regulating cell shape and tissue architecture; how do mechanical forces influence cell behaviour, specifically related to germ cell fate specification; and how does the mechanical microenvironment, defined by the extracellular matrix, affect organ development? To answer these questions, I will use multiple approaches such as genetics, CRISPR-Cas9-mediated genome editing, tissue-specific gene manipulations, live imaging combined with microfluidics, biophysical approaches such as laser ablations, -omics and theoretical modelling.

In your opinion, what are the other exciting things happening in the field?

Besides dissecting the role of mechanics in different developmental contexts, people are now focusing on how they become dysregulated under diseased conditions – such as changes in stiffness of extracellular matrix during aging, cancer progression and fibrosis, and how we can reverse them. With the advent of new tools for probing force, imaging technologies combined with microfluidics, and artificial intelligence to analyse large-scale data, changes in the mechanical properties of the cells and the force sensed by cells are being used as biomarkers for disease prognosis. Also, drug screening with small molecules is being carried out to target the mechanotransduction pathway for the treatment. Furthermore, insights from mechanobiology combined with 3D bioprinting and organoid technology are revolutionising the field of tissue engineering, which would open new avenues for repair and regenerative medicine.

What are your views on preprints?

Preprints are useful in multiple ways. It helps to rapidly disseminate research findings, open discussions and get feedback. For an early career researcher like me, it provides a citable date of publication which can be included in a CV, so they are useful when applying for jobs and funding. I also like that it could catch the attention of someone from a platform like preLights, which communicates your science to a broader audience. In some cases, journal editors might even invite preprints, which boosts our confidence in our work. Moreover, it might open new possibilities for collaborations.

Finally, what do you like to do outside of the lab?

In my free time, I take comfort and pleasure in drawing and painting. I attended fabric painting classes during a summer break after high school. Despite my busy schedule now, indulging in this hobby makes me feel happy and relaxed. I aspire to receive formal training in the future. I also have a keen interest in capturing intricate microscopic images. I've had several achievements in microphotography competitions, specifically at MBI, and one of my images has been the cover of the journal Genetics.

Priti Agarwal was interviewed by Alex Eve, Reviews Editor at Development. This piece has been edited and condensed with approval from the interviewee.