Novel WD-Repeat Protein Mip1p Facilitates Function of the Meiotic Regulator Mei2p in Fission Yeast

AUTOR(ES)

Shinozaki-Yabana, Satoko

FONTE

American Society for Microbiology

RESUMO

In fission yeast, the onset of meiosis is triggered by activation of the RNA-binding protein Mei2p. We screened for a high-copy-number suppressor of the ectopic meiosis induced by expression of an active form of Mei2p. Consequently we isolated a truncated form of a novel gene, named mip1, from a fission yeast genomic library. The mip1 gene encoded a protein of 1,313 amino acids which carried a WD-repeat motif in the C-terminal region and was apparently conserved among eukaryotes. Mip1p was cytoplasmic, and two-hybrid and immunoprecipitation analyses demonstrated that Mip1p was bound to Mei2p in vivo. Genetic evidence indicated that wild-type Mip1p was required for the function of Mei2p to induce meiosis and that the truncated form of it (Mip1-15p) dominantly interfered with Mei2p. Mip1p appeared to be involved also in conjugation, associating with Ste11p, which is a key transcription factor for sexual development. Furthermore, Mip1p was essential for cell growth, to which neither Mei2p nor Ste11p is relevant. These results suggest that Mip1p assists functional expression of a number of proteins required for proliferation and sexual development in fission yeast.

Documentos Relacionados

• Rrb1p, a Yeast Nuclear WD-Repeat Protein Involved in the Regulation of Ribosome Biosynthesis
• The WD-repeat protein superfamily in Arabidopsis: conservation and divergence in structure and function
• The Fission Yeast Meiotic Regulator Mei2p Forms a Dot Structure in the Horse-Tail Nucleus in Association with the sme2 Locus on Chromosome II
• Regulation of the p21-activated kinase (PAK) by a human Gβ-like WD-repeat protein, hPIP1
• Villidin, a Novel WD-repeat and Villin-related Protein from Dictyostelium, Is Associated with Membranes and the Cytoskeleton