A Class of Genes Affecting B Factor-Regulated Development in SCHIZOPHYLLUM COMMUNE

Twelve mutations affecting nuclear migration, a major developmental phase in Schizophyllum commune, display a complex pattern of complementation and recombination. They are expressed only when a genetic factor controlling this phase of development, the B incompatibility factor, is operative. All twelve mutations are linked to the B factor, nine in a cluster and three in distinct loci outside the cluster. A linear map cannot be constructed from the frequency of recombination. Complementation maps are not linear. There is little correlation between the complementation groups and the groups based on recombination. Many pairs of mutations that do not complement recombine with frequencies of 1.1% to 26.9%. The genes represented by the twelve mutations are located in a linked group of about 18 known genes involved in the specific phase of development controlled by the B factor.