title: Kluyveromyces lactis sexual pheromones. Gene structures and cellular responses to alpha-factor.
abstract: The Kluyveromyces lactis genes for sexual pheromones have been analyzed. The alpha-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 KlMFalpha1 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. MATalpha, Klsst2 mutants, which, by analogy to Saccharomyces cerevisiae, are defective in Galpha-GTPase activity, showed increased sensitivity to synthetic alpha-factor and increased capacity to mate. Additionally, Klbar1 mutants (putatively defective in alpha-pheromone proteolysis) showed delay in mating but sensitivity to alpha-pheromone. From these results, it can be deduced that the K. lactis MATa cell produces the homolog of the S. cerevisiaealpha-pheromone, whereas the MATalpha cell produces the a-pheromone.
authors.affiliation: Unidad de Biología Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México.
authors.forename: Laura
authors.initials: L
authors.lastname: Ongay-Larios
authors.forename: Rocio
authors.initials: R
authors.lastname: Navarro-Olmos
authors.forename: Laura
authors.initials: L
authors.lastname: Kawasaki
authors.forename: Nancy
authors.initials: N
authors.lastname: Velázquez-Zavala
authors.forename: Edith
authors.initials: E
authors.lastname: Sánchez-Paredes
authors.forename: Francisco
authors.initials: F
authors.lastname: Torres-Quiroz
authors.forename: Gerardo
authors.initials: G
authors.lastname: Coello
authors.forename: Roberto
authors.initials: R
authors.lastname: Coria
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D017353:Gene Deletion; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D007716:Kluyveromyces / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D000072235:Mating Factor; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D010675:Pheromones / Q000138:chemical synthesis / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D015398:Signal Transduction
chemical_list: D005656:Fungal Proteins; D010455:Peptides; D010675:Pheromones; D000072235:Mating Factor