Open AccessYeast Mutants That Produce a Novel Type of Ascus Containing Asci Instead of Spores
Author(s) -
Zhixiong Xue,
Xiaoyin Shan,
Alex Sinelnikov,
Teri Mélèse
Publication year - 1996
Publication title -
genetics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.792
H-Index - 246
eISSN - 1943-2631
pISSN - 0016-6731
DOI - 10.1093/genetics/144.3.979
Subject(s) - ascus (bryozoa) , biology , cytokinesis , meiosis , mitosis , microbiology and biotechnology , genetics , cell cycle , spore , mutant , saccharomyces cerevisiae , yeast , sporogenesis , ploidy , cell division , cell , gene , botany , ascospore
Tetraploid yeast cells lacking BFR1 or overexpressing an essential gene BBP1 produce a novel type of ascus that contains asci instead of spores. We show here that the asci within an ascus likely arise because a/alpha spores undergo a second round of meiosis. Cells depleted of Bbp1p or lacking Bfr1p are defective in a number of processes such as nuclear segregation, bud formation, cytokinesis and nuclear spindle formation. Furthermore, deletion of BFR1 or overexpression of BBP1 leads to an increase in cell ploidy, indicating that Bfr1p and Bbp1p play roles in both the mitotic cell cycle and meiosis. Bfr1p and Bbp1p interact with each other in a two hybrid assay, further suggesting that they might form a complex important for cell cycle coordination.