Biophysical Society Bulletin | November 2024

Publications

Know the Editor Yuval Ebenstein Tel-Aviv University Associate Editor Biophysical Reports

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Yuval Ebenstein

What are you currently working on that excites you?? In the last year, I have opened a new front of research in my lab trying to connect a psychological state of an individual with molecular transformations in the brain. Specifically, epigenetic patterns of chemical modifications along genomic DNA in brain cells have been shown to change in response to various types of mental stress. Our lab has developed a tool box for single-molecule studies of DNA modifications, which we are now utilizing to map various mouse brain regions for changes associated with depression in depressed versus happy mice. At a cocktail party of non-scientists, how would you explain what you do? Hi, I’m a physical epigeneticist. I’m trying to find out if, and how, a chemical code on our DNA makes us who we are. Each one of us has a unique and personal genome, but all the different cell types that make us have exactly the same genetic code—our personal genome. How can different cell types display distinct shape and function despite having the same execution code? It turns out that additional informa tion is encoded by chemical modifications to the DNA bases. This epigenetic code controls which parts of the genome are used by each type of cell according to its function (skin, liver, etc.). The modified DNA bases may be converted back to their original state, thus allowing cells to write and erase functional information—a molecular memory. My lab develops tech niques to read epigenetic patterns on DNA and relate them to physiological conditions such as cancer. We profile DNA molecules one by one, which provides extreme sensitivity for cancer diagnosis. It also allows us to measure epigenetic entropy. But that’s a whole different story.

Biophysical Reports Growing bacterial colonies harness emergent genealogical demixing to regulate organizational entropy Garima Rani and Anupam Sengupta “Spatiotemporal distribution of bacteria has far-reaching ramifications in the ecology and evolution of bacterial species and their consortia. Many species are surface associated, yet how they distribute genealogically, i.e., how daughter cells distribute in relation to their mother cells, specifically during the early stages of biofilm formation, remains unknown. By analyzing expanding colonies using a custom-built, label-free algorithm, the authors tracked bacterial growth, revealing distinct self-similar genealogical enclaves that intermix over time. While biological activity determines their intermixing dynamics, emergent topological defects at the interfaces mediate the finger-like morphology of interfacial domains. The results demonstrate that proximity to kith and kin—both spatial and genealogical—is intrinsically encoded in growth from an early developmental stage, signifying its role in medi ating fitness and viability.”

Version of Record Published August 21, 2024 DOI: https:/doi.org/10.1016/j.bpr.2024.100175

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BPS supported 17 science fairs across the United States in 2024.

November 2024

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