Open AccessKluyveromyces lactis sexual pheromones. Gene structures and cellular responses to α‐factor
Author(s) -
OngayLarios Laura,
NavarroOlmos Rocio,
Kawasaki Laura,
VelázquezZavala Nancy,
SánchezParedes Edith,
TorresQuiroz Francisco,
Coello Gerardo,
Coria Roberto
Publication year - 2007
Publication title -
fems yeast research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.991
H-Index - 92
eISSN - 1567-1364
pISSN - 1567-1356
DOI - 10.1111/j.1567-1364.2007.00249.x
Subject(s) - kluyveromyces lactis , biology , gene , sex pheromone , pheromone , genetics , mutant , saccharomyces cerevisiae , kluyveromyces , mating type , mating
The Kluyveromyces lactis genes for sexual pheromones have been analyzed. The α‐factor gene encodes a predicted polypeptide of 187 amino acid residues containing four tridecapeptide repeats (WSWITLRPGQPIF). A nucleotide blast search of the entire K. lactis genome sequence allowed the identification of the nonannotated putative a ‐pheromone gene that encodes a predicted protein of 33 residues containing one copy of the dodecapeptide a ‐factor (WIIPGFVWVPQC). The role of the K. lactis structural genes KlMF α 1 and KlMFA1 in mating has been investigated by the construction of disruption mutations that totally eliminate gene functions. Mutants of both alleles showed sex‐dependent sterility, indicating that these are single‐copy genes and essential for mating. MAT α, Klsst2 mutants, which, by analogy to Saccharomyces cerevisiae , are defective in Gα‐GTPase activity, showed increased sensitivity to synthetic α‐factor and increased capacity to mate. Additionally, Klbar1 mutants (putatively defective in α‐pheromone proteolysis) showed delay in mating but sensitivity to α‐pheromone. From these results, it can be deduced that the K. lactis MAT a cell produces the homolog of the S. cerevisiae α‐pheromone, whereas the MAT α cell produces the a ‐pheromone.