Blog Archive

Αλέξανδρος Γ. Σφακιανάκης

Thursday, December 17, 2020

The role of gene dosage in budding yeast centrosome scaling and spontaneous diploidization

Alexandros G.Sfakianakis shared this article with you from Inoreader

journal.pgen.1008911.g005&size=inline

by Jingjing Chen, Zhiyong Xiong, Danny E. Miller, Zulin Yu, Scott McCroskey, William D. Bradford, Ann M. Cavanaugh, Sue L. Jaspersen

Ploidy is the number of whole sets of chromosomes in a species. Ploidy is typically a stable cellular feature that is critical for survival. Polyploidization is a route recognized to increase gene dosage, improve fitness under stressful conditions and promote evolutionary diversity. However, the mechanism of regulation and maintenance of ploidy is not well characterized. Here, we examine the spontaneous diploidization associated with mutations in components of the Saccharomyces cerevisiae centrosome, known as the spindle pole body (SPB). Although SPB mutants are associated with defects in spindle formation, we show that two copies of the mutant in a haploid yeast favors diploidization in some cases, leading us to speculate that the increased gene dosage in diploids 'rescues' SPB duplication defects, allowing cells to successfully propagate with a stable diploid karyotype. This copy number-based rescue is linked to SPB scaling: certain SPB subcomplexes do not scale or only minimally scale with ploidy. We hypothesize that lesions in structures with incompatible allometries such as the centrosome may drive changes such as whole genome duplication, which have shaped the evolutionary landscape of many eukaryotes.
View on the web

No comments:

Post a Comment