ABSTRACT
First Person is a series of interviews with the first authors of a selection of papers published in Journal of Cell Science, helping early-career researchers promote themselves alongside their papers. Shalini Umachandran is first author on ‘ A PKC that controls polyphosphate levels, pinocytosis and exocytosis, regulates stationary phase onset in Dictyostelium’, published in JCS. Shalini is a PhD student in the lab of Ramamurthy Baskar at Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology-Madras, Chennai, India, investigating the role of PKC in delaying stationary phase onset in Dictyostelium.
Shalini Umachandran
How would you explain the main findings of your paper in lay terms?
The decision of cells to stop multiplying is crucial in determining the size and shape of organs, and survival in stressful conditions. A variety of secreted signals are sensed by cells, and these keep their growth under check. I identified a particular protein that can regulate these signals, to either keep cells growing or induce them to stop dividing.
Were there any specific challenges associated with this project? If so, how did you overcome them?
Initially, we were not able to pin down the reason why our mutant cells stopped multiplying at an earlier stage than normal cells. Then, another lab identified inorganic polyphosphate as a potent inhibitor of proliferation in wild-type cells, and we found this was also the case in our mutant. We were therefore able to redirect our research and find the answers to our questions. Also, after a prolonged lockdown for almost a year, we had to start many experiments afresh and this led to a considerable delay, but eventually we could complete the planned experiments.
When doing the research, did you have a particular result or ‘eureka’ moment that has stuck with you?
Yes, when we observed PkcA–GFP localization in vesicles and at the cell membrane. It was beautiful to see how dynamically the vesicles fused with the membrane. And this really supported our hypothesis that PkcA regulates endocytosis as well as exocytosis.
PkcA–GFP localization in LysoTracker Red-positive vesicles. PkcA–GFP-containing cells were incubated with 200 nM LysoTracker Red. Scale bars: 10 µm.
Why did you choose Journal of Cell Science for your paper?
First, the longstanding reputation of JCS is one reason. Second, the comprehensive mechanical insights are apt for JCS. Third, we expect that the work will be of interest to a larger community working on stationary phase regulation and cell proliferation.
Have you had any significant mentors who have helped you beyond supervision in the lab? How was their guidance special?
My PhD mentor, Dr R. Baskar, has been exceptional in motivating me to do better work. He is always open to discussion. He was a great support throughout my PhD and also understands my limitations and tries to work around them or, when necessary, push me through them. My mentor from my undergrad studies, Dr Arunava Das, also taught me a lot about how to pursue a project and plan experiments. He taught me how to be independent in my research work and also how to have peace at the workplace. Finally, Dr N. S. Vasanthi inspired me to be perfect in every small thing we do. Being a teacher and scientist herself, she taught how to manage both personal and professional life.
What's next for you?
Currently I am wrapping up my thesis work. I will start looking for postdoctoral positions soon. I would like to study exosomes and secretory vesicles, and their role in regulating cell proliferation.
Tell us something interesting about yourself that wouldn't be on your CV
I love dancing and spend a lot of time with my kids. So when I am not working, I like to dance with my son. I also love reading science fiction; I can read for an entire day.
Shalini Umachandran's contact details: Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology-Madras, Chennai, India.
E-mail: shalinichandran12@gmail.com
