Meet one of our early-career scientists at Sanford Burnham Prebys Medical Discovery Institute: Jimmy Massenet, PhD, a postdoctoral researcher in the lab of Pier Lorenzo Puri, MD. Massenet studies changes in the way DNA is organized inside muscle cells that contribute to muscle-wasting diseases.
Massenet also is the 2026 recipient of the Fishman Fellowship, which provides exceptional Sanford Burnham Prebys postdocs with a two-year fellowship award. This fellowship is bestowed every other year to the young scientist who is ranked highest by the Fishman Awards selection committee.
When and how did you become interested in science?
I’ve always been very curious about my environment and how things work. This inclination led me to become fascinated in cell biology when I started to study it in school. I found it fascinating seeing how cells function, especially the way everything happens mechanically inside our cells.
As I progressed to university studies, I discovered epigenetics and the way the genome can be changed with transient modifications. I found that so amazing that I wanted to continue in this direction.
What are the key areas of research you focus on?
I’m studying a muscle-wasting disease called myositis. It’s an inflammatory muscular disease that causes patients to develop a progressive inflammation in their muscles. Their muscle size starts to shrink and they lose their strength.
To better understand this disease, I am investigating a protein that is called CTCF. It’s an architect of our DNA genome that works by folding the DNA in loops and allows the creation of a three-dimensional structure in our nuclei. CTCF is altered in patients suffering from myositis and seems to worsen patient outcomes, so it may represent a target for future therapies.
What motivates you about your research?
I like that no two days are the same as a scientist. In this job, we always have new experiments to do. Each day you’re going to learn something new, which I find exciting.
And sometimes you have the absolute thrill of finding something new that no one in the world has discovered before.
What do you like about working here?
I love the team my mentor has assembled in the Puri lab. I worked in the muscle research field before joining Sanford Burnham Prebys and knew I wanted to apply to work here to be a part of this group.
I have worked in France in smaller institutes, and it has given me an appreciation for the technology we have at Sanford Burnham Prebys. Our core facilities here are outstanding and can process samples in a few days that would previously have taken weeks or even months.
What are your career goals?
I want to continue in academia because I like the nature of this job. I enjoy taking the lead on a research project and deciding to pursue a particular direction. My goal then is to open my own lab and continue to focus on chromatin organization.
There are many proteins beyond CTCF that are linked to the three-dimensional structure of the genome that need to be studied. If we can understand how they contribute to disease, I think that will make a real difference in terms of improving the diagnosis of patients as well as potentially the development of new treatments.
What do you enjoy doing when you’re not in the lab?
I love to run, especially trail running, and the San Diego area is amazing for that. I have done some ultra-marathons here and those were very rewarding experiences. I enjoy going to the gym, too, and when I’m home, I dabble in some painting.
Postdocs at Sanford Burnham Prebys are pushing the boundaries of science every day through curiosity, collaboration, and innovation. This series highlights their unique journeys, what inspires their work, and the impact they’re making across our labs.