ABSTRACT
First Person is a series of interviews with the first authors of a selection of papers published in Journal of Cell Science, helping researchers promote themselves alongside their papers. Nikhil Dev Narendradev is first author on ‘ Endosomal RFFL ubiquitin ligase regulates mitochondrial morphology by targeting mitofusin 2’, published in JCS. Nikhil Dev is a PhD student in the lab of Srinivasa Murty Srinivasula at Indian Institute of Science Education and Research Thiruvananthapuram, India, working on understanding the crosstalk between different organelles and their regulation via post translational modifications mediated by ubiquitin protein ligases.
Nikhil Dev Narendradev
How would you explain the main findings of your paper in lay terms?
The human body is made up of billions of cells, each functioning like a tiny, self-contained unit. Inside these cells are specialized compartments, like mitochondria, which produce energy, and endosomes, which help sort and transport materials. These compartments constantly communicate to keep the cell healthy. When this coordination breaks down, it can lead to diseases like cancer and neurodegenerative disorders. One key player in maintaining healthy mitochondria is a protein called MFN2, which helps control their shape and function. Changes or mutations in MFN2 are reported in Charcot–Marie–Tooth disease type 2A (CMT2A), a genetic neurological disorder. In our study, we discover that RFFL, a protein located on endosomes, also contributes to the quality of mitochondria by associating with MFN2. Cells lacking the RFFL protein exhibit overly large and excessively fused mitochondria with impaired function. We also find that RFFL affects how cells handle fats. Cells with more RFFL have more lipid droplets but show less overlap between these droplets and mitochondria. Overall, our findings reveal that endosomes, tiny compartments inside cells, help keep the cell's energy producers, the mitochondria, in shape and balanced. This discovery not only deepens our understanding of how cells stay healthy but also offers new hope for treating diseases like CMT2A, which currently have no cure. Our study identifies RFFL could be a potential target for therapeutic intervention.
Were there any specific challenges associated with this project? If so, how did you overcome them?
One of the main challenges in the project was to experimentally demonstrate the direct ubiquitylation of MFN2 by RFFL using recombinant proteins. As MFN2 is a transmembrane protein, purifying recombinant MFN2 from a bacterial expression system proved very challenging. After trying several approaches, we decided to co-express RFFL and MFN2 in bacteria instead of purifying them individually. This allowed us to use an enriched RFFL–MFN2 complex for in vitro ubiquitylation assays. This helped us to show for the first time, an E3 ligase directly ubiquitylating MFN2.
When doing the research, did you have a particular result or ‘eureka’ moment that has stuck with you?
The surprising and interesting part of the project was when we found that RFFL targets MFN1 and MFN2, proteins involved in mitochondrial fusion, but not DRP1, a protein involved in mitochondrial fission. Specificity of RFFL for the fusion machinery is interesting, and it's something I'm intrigued to investigate further at some point.
Why did you choose Journal of Cell Science for your paper?
The Journal of Cell Science (JCS) has a reputation for publishing high-quality and solid findings, an important consideration in today's publishing landscape, where many predatory journals exist. As part of a non-profit organization, JCS is driven by the interests of the scientific community. One feature I particularly appreciate is its transparent peer review process, including the publication of peer review reports alongside accepted manuscripts, which adds an extra layer of accountability and insight. Additionally, our institution has a ‘Read & Publish’ agreement with JCS, allowing us to publish Open Access without incurring huge article processing charges. These factors collectively made us consider JCS a good home for our manuscript.
Confocal image of A549 cells, showing cellular components. Neutral lipids are stained with HCS LipidTOX (yellow), mitochondria are stained with MitoTracker Red CMXRos (magenta) and RFFL is tagged with EGFP (cyan).
Confocal image of A549 cells, showing cellular components. Neutral lipids are stained with HCS LipidTOX (yellow), mitochondria are stained with MitoTracker Red CMXRos (magenta) and RFFL is tagged with EGFP (cyan).
Have you had any significant mentors who have helped you beyond supervision in the lab? How was their guidance special?
There are many people to whom I am deeply grateful for their unwavering support, besides my PhD thesis mentor. I've had the privilege of working alongside senior researchers and engaging with leading experts in the field, from whom I learned both technical skills and a finer understanding of the subject. Equally enriching was the experience of teaching and mentoring undergraduate students, a process that indirectly taught me invaluable lessons.
Who are your role models in science? Why?
There are many, especially my mentors, because I have been directly influenced by their thinking and I always admired how they handled different situations. I also have huge admiration for people who made open-access tools and resources for the benefit of everyone.
What's next for you?
I am planning to continue my path in academia, first by taking a postdoc position. I am excitedly looking forward to a more adventurous journey in the lab and, in the process, helping to solve more basic disease biology problems.
Tell us something interesting about yourself that wouldn't be on your CV
I spend a lot of time fixing electronic gadgets and doing DIY projects, which I consider hobbies.
Nikhil Dev Narendradev’s contact details: Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala PO, Vithura, Thiruvananthapuram 695551, Kerala, India.
E-mail: [email protected]
