EVIDENCE FOR A MULTI-ALLELIC HETEROKARYON INCOMPATIBILITY (HET) LOCUSDETECTED BY HYBRIDIZATION AMONG 3 HETEROKARYON-COMPATIBILITY (H-C) GROUPS OF ASPERGILLUS-NIDULANS
Rbg. Dales et al., EVIDENCE FOR A MULTI-ALLELIC HETEROKARYON INCOMPATIBILITY (HET) LOCUSDETECTED BY HYBRIDIZATION AMONG 3 HETEROKARYON-COMPATIBILITY (H-C) GROUPS OF ASPERGILLUS-NIDULANS, Heredity, 70, 1993, pp. 537-543
A strain of heterokaryon-compatibility (h-c) group A was crossed sexua
lly to strains of h-cB and h-cGL of Aspergillus nidulans. A back-cross
ing programme established that there were seven hetero-allelic heterok
aryon compatibility (het) genes controlling somatic incompatibility be
tween strains of h-cA and h-cB. A similar back-crossing programme betw
een strains of h-cA and h-cGL confirmed that these two groups differ a
t six het loci. Previous work has shown that h-cB differs from h-cGL a
t two het loci, hetA on linkage group V and hetB on linkage group VI.
As an allelic difference at a single het locus is enough to cause two
strains to be heterokaryon incompatible, 15 alleles spread over seven
het loci are necessary to explain the h-cA, h-cB, h-cGL triangular com
patibility relationship. One het locus is multi-allelic and this locus
must be either hetA or hetB.