ISSN:
1617-4623
Keywords:
Schizophyllum commune
;
Homeodomain
;
Homeobox
;
Mating type
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The Aα mating-type locus is one of four master regulatory loci controlling sexual development in Schizophyllum commune. The Aα locus contains two homeobox genes, Y and Z, encoding two homeodomain-related proteins, Y and Z, Y and Z are each multi-allelic genes. When haploid strains form fusion cells, only particular combinations of Y and Z alleles activate Aα-regulated sexual development. The role of the putative homeodomain was examined in several Y and Z alleles by site-directed mutagenesis of regions critical to secondary structure and function of homeodomains. Mutations of the Z homeobox do not affect the function of Z proteins in Aα-activated development, but mutations of Yhomeoboxes destroy the ability of Y proteins to activate development. We conclude that only one of two Aα homeodomain-related regulators relies upon the homeodomain motif to effect gene expression in sexual development. This conclusion affords a refinement of our working hypothesis for the mechanism by which Aα proteins may regulate target gene expression. On the basis of our results with the Z protein, we speculate that the DNA-binding motifs of some transcriptional regulators may be lost or modified during evolution once these regulators have been recruited to participate in complexes with other DNA-binding proteins.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00285460
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