Dear Biology Students, Postdocs, and Faculty,
Next week for our Faculty Seminar Series at 1:00 p.m. on Monday, November 24th, we will have a talk by Dr. Schragi Schwartz of the Weizmann Institute of Science. Dr. Schwartz will present a talk titled “Methyl Marks and Molecular Heat Shields: How RNA Modifications Shape Function and Adaptation” .
Talk Abstract: Methyl Marks and Molecular Heat Shields: How RNA Modifications Shape Function and Adaptation
Similar to DNA and proteins, RNA undergoes extensive post-synthetic modification. To
date, more than 170 distinct modifications have been documented, installed by a
diverse set of typically highly conserved enzymes, many of which play essential roles in
RNA structure and function and are implicated in human disease.
In the first part of my talk, I will focus on N6-methyladenosine (m6A), the most
prevalent internal modification on mRNA. Although m6A is found at hundreds of
thousands of sites transcriptome-wide, the rules governing its deposition remained
unclear. I will describe our advances in deciphering this “m6A code,” which provided key
insights into the determinants of specificity and the functional consequences of this
modification.
In the second part, I will turn to ribosomal RNA (rRNA) modifications, which we
dissected using a newly developed genomic platform that enables systematic profiling
of 16 distinct modifications across dozens of samples in parallel. Applying this approach
to species spanning the tree of life—particularly unicellular extremophiles that thrive
under harsh physical, chemical, or biological conditions—we discovered striking
evolutionary patterns. While dynamic rRNA modifications are rare in mesophiles, in
extreme hyperthermophiles nearly half of all modifications proved to be dynamic.
I will highlight one example: a conserved module of tandem m5C–ac4C modifications,
co-induced at elevated temperatures by enzymes that are intrinsically temperature-
responsive and essential for growth under thermal stress. By integrating genomic,
biophysical, and structural analyses, we revealed a synergistic thermostabilizing
function of this modification pair.
Together, these findings shed light on the critical contribution of rRNA modifications to
ribosome stability, enabling ribosomes to preserve their structural integrity even at near-
boiling temperatures that would otherwise cause denaturation.
Some details about his research and publications can be found at:
https://www.weizmann.ac.il/molgen/schwartz/
Looking forward to seeing you!
Maya
