BIOGRID CURATED DATA FOR PUBLICATION: A genetic analysis of interactions with Spc110p reveals distinct functions of Spc97p and Spc98p, components of the yeast gamma-tubulin complex.

Protein-Protein, Genetic, and Chemical Interactions for Nguyen T (1998):A genetic analysis of interactions with Spc110p reveals distinct functions of Spc97p and Spc98p, components of the yeast gamma-tubulin complex. curated by BioGRID (https://thebiogrid.org); ABSTRACT: The spindle pole body (SPB) in Saccharomyces cerevisiae functions as the microtubule-organizing center. Spc110p is an essential structural component of the SPB and spans between the central and inner plaques of this multilamellar organelle. The amino terminus of Spc110p faces the inner plaque, the substructure from which spindle microtubules radiate. We have undertaken a synthetic lethal screen to identify mutations that enhance the phenotype of the temperature-sensitive spc110-221 allele, which encodes mutations in the amino terminus. The screen identified mutations in SPC97 and SPC98, two genes encoding components of the Tub4p complex in yeast. The spc98-63 allele is synthetic lethal only with spc110 alleles that encode mutations in the N terminus of Spc110p. In contrast, the spc97 alleles are synthetic lethal with spc110 alleles that encode mutations in either the N terminus or the C terminus. Using the two-hybrid assay, we show that the interactions of Spc110p with Spc97p and Spc98p are not equivalent. The N terminus of Spc110p displays a robust interaction with Spc98p in two different two-hybrid assays, while the interaction between Spc97p and Spc110p is not detectable in one strain and gives a weak signal in the other. Extra copies of SPC98 enhance the interaction between Spc97p and Spc110p, while extra copies of SPC97 interfere with the interaction between Spc98p and Spc110p. By testing the interactions between mutant proteins, we show that the lethal phenotype in spc98-63 spc110-221 cells is caused by the failure of Spc98-63p to interact with Spc110-221p. In contrast, the lethal phenotype in spc97-62 spc110-221 cells can be attributed to a decreased interaction between Spc97-62p and Spc98p. Together, these studies provide evidence that Spc110p directly links the Tub4p complex to the SPB. Moreover, an interaction between Spc98p and the amino-terminal region of Spc110p is a critical component of the linkage, whereas the interaction between Spc97p and Spc110p is dependent on Spc98p.

蛋白质-蛋白质、遗传和化学相互作用数据集，源自Nguyen T (1998)的研究：通过对Spc110p的相互作用进行遗传分析，揭示了酵母γ-微管蛋白复合物成分Spc97p和Spc98p的特定功能。数据由BioGRID（https://thebiogrid.org）整理；摘要：在有丝分裂中，酵母菌Saccharomyces cerevisiae的纺锤体极体（SPB）充当微管组织中心。Spc110p是该极体不可或缺的结构成分，横跨多层膜状细胞器的中央和内层板。Spc110p的氨基端面向内层板，该亚结构为纺锤体微管的辐射提供起点。本研究通过合成致死筛选，旨在识别增强温度敏感型spc110-221等位基因表型的突变，该等位基因编码氨基端的突变。筛选确定了SPC97和SPC98中的突变，这两个基因编码酵母Tub4p复合物的成分。spc98-63等位基因仅与编码Spc110p氨基端突变的spc110等位基因呈现合成致死性。相反，spc97等位基因与编码Spc110p氨基端或羧基端突变的spc110等位基因呈现合成致死性。通过双杂交实验，我们证明了Spc110p与Spc97p和Spc98p的相互作用并不等同。Spc110p的氨基端在两个不同的双杂交实验中均表现出与Spc98p的强烈相互作用，而Spc97p与Spc110p的相互作用在一个菌株中不可检测，在另一个菌株中则产生微弱的信号。额外的SPC98拷贝增强了Spc97p与Spc110p之间的相互作用，而额外的SPC97拷贝干扰了Spc98p与Spc110p之间的相互作用。通过测试突变蛋白之间的相互作用，我们证实了spc98-63 spc110-221细胞中的致死表型是由于Spc98-63p无法与Spc110-221p相互作用所致。相比之下，spc97-62 spc110-221细胞中的致死表型可以归因于Spc97-62p与Spc98p之间相互作用减弱。综上所述，这些研究提供了证据，表明Spc110p直接将Tub4p复合物与SPB联系起来。此外，Spc98p与Spc110p氨基端区域的相互作用是这一联系的关键组成部分，而Spc97p与Spc110p的相互作用则依赖于Spc98p。