Poster abstracts
Poster number 29 submitted by Wenfang Liu
Novel P-body like foci: the cellular site of tubulin autoregulation?
Wenfang Liu (MCDB program), Zachary Hurst (MCDB program)
Abstract:
Processing-bodies (P-bodies) are subcellular ribonucleoprotein (RNP) granules that contain translationally repressed mRNAs as well as proteins involved in mRNA decay. P-bodies are conserved from yeast to mammals and have been suggested to be sites of mRNA degradation and/or storage. Traditional P-bodies form in response to a variety of cellular stresses including glucose starvation and osmotic stress. Interestingly, previous work from our lab has shown that novel P-body-like foci are induced by microtubule disruption. For example, these latter structures form when cells are treated with microtubule-destabilizing agents, like benomyl, and in mutants lacking chaperones required for the proper folding of tubulin monomers. These novel granules differ with respect to their overall protein composition and the manner in which their induction is regulated. For instance, although many known P-body proteins are present in these benomyl-induced granules (BIGs), several key core constituents normally required for foci formation are absent.
Our current efforts in the lab are focused on characterizing the potential function(s) of these BIGs and the underlying reasons for their induction upon microtubule disruption. One intriguing possibility is that these foci are the cellular sites of a process known as tubulin autoregulation in animal cells. During autoregulation, tubulin mRNAs that are associated with ribosomes are targeted for degradation by an unknown mechanism when microtubule integrity is disrupted. My work has been focused on determining whether tubulin autoregulation occurs in yeast and if BIGs represent sites of this novel mRNA turnover.
References:
1. Luo, Y., Na, Z. & Slavoff, S. A. (2018) P-Bodies: Composition, Properties, and Functions. Biochemistry 57, 2424–2431.
2. Sweet, T. J., Boyer, B., Hu, W., Baker, K. E. & Coller, J. (2207) Microtubule disruption stimulates P-body formation. RNA 13, 493–502.
3. Hurst, Zachary, Wenfang Liu, Qian Shi, and Paul K. Herman. (2022) A distinct P-body-like granule is induced in response to the disruption of microtubule integrity in Saccharomyces cerevisiae. Genetics 22, iyac105.
4. Gay, David A., Tim J. Yen, Joseph TY Lau, and Don W. Cleveland. (1987) Sequences that confer β-tubulin autoregulation through modulated mRNA stability reside within exon 1 of a β-tubulin mRNA. Cell 50, 671-679.
Keywords: RNP granules, P-bodies, tubulin autoregulation