| Title: | Heterodimerization of the yeast MATa1 and MAT alpha 2 proteins is mediated by two leucine zipper-like coiled-coil motifs |
| Author(s): | Ho CY; Adamson JG; Hodges RS; Smith M; |
| Address: | "Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, Canada" |
| DOI: | 10.1002/j.1460-2075.1994.tb06394.x |
| ISSN/ISBN: | 0261-4189 (Print) 1460-2075 (Electronic) 0261-4189 (Linking) |
| Abstract: | "The yeast Saccharomyces cerevisiae has three cell types distinguished by the proteins encoded in their mating type (MAT) loci: the a and alpha haploids, which express the DNA binding proteins a1 and alpha 1 and alpha 2, respectively, and the a/alpha diploid which expresses both a1 and alpha 2 proteins. In a/alpha cells, a1-alpha 2 heterodimers repress haploid-specific genes, while alpha 2 homodimers repress a-specific genes, indicating a dual regulatory function for alpha 2 in mating type control. a1 does not form homodimers. We have identified two sequences in the alpha 2 N-terminal domain which contain the 3,4-hydrophobic heptad repeat pattern characteristic of coiled-coils. Mutational analyses show that both sequences are important to a1-alpha 2 heterodimerization. We propose that these two sequences associate in a coiled-coil-like manner with a sequence within a1 which bears two adjacent, overlapping 3,4-hydrophobic heptad repeats. This model, which describes a novel dimerization motif for homeodomain proteins, also provides a mechanism by which a1-a1 homodimerization is prevented" |
| Keywords: | "Amino Acid Sequence Base Sequence Biopolymers Cysteine/genetics DNA Mutational Analysis DNA, Fungal Leucine/genetics *Leucine Zippers Mating Factor Molecular Sequence Data Mutation Peptides/chemistry/genetics/*metabolism Protein Conformation Repressor Pro;" |
| Notes: | "MedlineHo, C Y Adamson, J G Hodges, R S Smith, M eng Research Support, Non-U.S. Gov't England 1994/03/15 EMBO J. 1994 Mar 15; 13(6):1403-13. doi: 10.1002/j.1460-2075.1994.tb06394.x" |
