Sarah M Hanna, Bita Tavafoghi, Jun-Song Chen, Isaac Howard, Liping Ren, Alaina H Willet, Kathleen L Gould
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引用次数: 0
Abstract
Centrosomes and spindle pole bodies (SPB) are important for mitotic spindle formation and also serve as signaling platforms. In the fission yeast Schizosaccharomyces pombe, genetic ablation and high-resolution imaging indicate that the ɑ-helical Ppc89 is central to SPB structure and function. Here, we developed and characterized conditional and truncation mutants of ppc89. Alleles with mutations in two predicted ɑ-helices near the C-terminus were specifically defective in anchoring Sid4, the scaffold for the septation initiation network (SIN), and proteins dependent on Sid4 (Cdc11, Dma1, Mto1 and Mto2). Artificial tethering of Sid4 to the SPB fully rescued these ppc89 mutants. Another ppc89 allele had mutations located throughout the coding region. While this mutant was also defective in Sid4 anchoring, it displayed additional defects including fragmented SPBs and forming and constricting a second cytokinetic ring in one daughter cell. These defects were shared with a ppc89 allele truncated of the most C-terminal predicted ɑ-helices that is still able to recruit Sid4 and the SIN. We conclude that Ppc89 not only tethers the SIN to the SPB but is also necessary for the integrity of the SPB and faithful coordination of cytokinesis with mitosis.
期刊介绍:
G3: Genes, Genomes, Genetics provides a forum for the publication of high‐quality foundational research, particularly research that generates useful genetic and genomic information such as genome maps, single gene studies, genome‐wide association and QTL studies, as well as genome reports, mutant screens, and advances in methods and technology. The Editorial Board of G3 believes that rapid dissemination of these data is the necessary foundation for analysis that leads to mechanistic insights.
G3, published by the Genetics Society of America, meets the critical and growing need of the genetics community for rapid review and publication of important results in all areas of genetics. G3 offers the opportunity to publish the puzzling finding or to present unpublished results that may not have been submitted for review and publication due to a perceived lack of a potential high-impact finding. G3 has earned the DOAJ Seal, which is a mark of certification for open access journals, awarded by DOAJ to journals that achieve a high level of openness, adhere to Best Practice and high publishing standards.