Far3p domains involved in the interactions of Far proteins and pheromone-induced cell cycle arrest in budding yeast.
Far3p (factor arrest), a protein that interacts with Far7-11p, is required for the pheromone-mediated cell cycle arrest in G1 phase. We used a combination of computational and experimental strategies to identify the Far3p self-association, to map the Far3p domains that interact with Far3p itself and with other Far proteins, and to reveal the importance of the two coiled-coil motifs of Far3p in the integrity and function of the Far complex. We show that Far3p self-associates through its central region and its C-terminal coiled-coil domain, that the amino acid 61-100 region of Far3p interacts with Far7p, and that the Far3p N-terminal coiled-coil domain interacts with Far9p and Far10p. Mutation of the N-terminal coiled coil disrupts the interactions of Far3p with Far9p and Far10p, and mutation of the C-terminal domain weakens the Far3p self-interaction. Although the N- and C-terminal coiled-coil mutants reserve some of the interactions with itself and some other Far proteins, both mutants are defective in the pheromone-mediated G1 arrest, indicating that both coiled-coil motifs of Far3p are essential for the integrity and the function of the Far complex.
Lai
Fenju
F
School of Life Sciences, Sun Yat-Sen University, Guangzhou, China Section of Biochemistry and Cell Biology, Division of Life Science, and Center for Cancer Research, Hong Kong University of Science and Technology, Hong Kong, China.
Wu
Rentian
R
Wang
Jiafeng
J
Li
Chunming
C
Zou
Lan
L
Lu
Yongjun
Y
Liang
Chun
C
D002453:Cell Cycle / Q000187:drug effects*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism; D010675:Pheromones / Q000378:metabolism*; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D025941:Protein Interaction Mapping; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*
D018797:Cell Cycle Proteins; C096755:FAR3 protein, S cerevisiae; D050505:Mutant Proteins; D010675:Pheromones; D029701:Saccharomyces cerevisiae Proteins