Functional analysis of the homeodomain-related proteins of the A alpha locus of Schizophyllum commune.
DNA-mediated transformation was used to correlate function with putative genes from three alternative A alpha mating-type loci (A alpha 1, A alpha 3, and A alpha 4) of Schizophyllum commune. Each DNA was tested in at least nine haploid strains, one for each of the nine A alpha mating types found in the world-wide population of S. commune. The Y and Z genes (tentatively identified by sequence analysis elsewhere) individually activate A alpha-regulated development when transformed into any strain with a different A alpha mating type. The only exceptions are when the Y alleles of A alpha 3 or A alpha 4 (i.e., Y3 or Y4, respectively) are introduced into an A alpha 1 strain (the A alpha 1 locus encodes Y1 but lacks a Z gene). These observations indicate that A alpha-regulated development is activated by the interaction (direct or indirect) of products from different genes (e.g., Z3 and Y1) rather than from different alleles of the same gene (e.g., Y1 and Y3). Therefore, the activating interaction is of the form ZiYj where i not equal to j and i and j are the A alpha mating types from which the Z and Y polypeptides, respectively, are derived. Transformations with truncated or mutagenized genes begin to define essential regions of the genes and their products. Activity is in some cases dependent upon the particular A alpha mating type of the recipient. A working hypothesis for the activation of A alpha-regulated development is proposed.
Department of Botany, University of Vermont, Burlington 05405.
C A
CA
Specht
M M
MM
Stankis
L
L
Giasson
C P
CP
Novotny
R C
RC
Ullrich
D003433:Crosses, Genetic; D004271:DNA, Fungal / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D005801:Genes, Homeobox; D049770:Genes, Mating Type, Fungal; D005838:Genotype; D018398:Homeodomain Proteins; D008957:Models, Genetic; D012567:Schizophyllum / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors; D014170:Transformation, Genetic
D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D018398:Homeodomain Proteins; D014157:Transcription Factors; C075905:homeodomain protein, Schizophyllum commune