Worm Breeder's Gazette 9(2): 97
These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.
We are continuing our study of four EMS-induced autosomal extragenic suppressors of the semidominant allele her-1(n695) that were described in the previous Newsletter (WBG vol. 9, No. 1, p.70). n1091 and ct49 appear to be allelic and define a locus on LG III (sup III). n1092 and n1102 appear to be allelic and define a locus on LG V (sup v). When homozygous, each of these mutations strongly suppresses the Tra and Egl phenotypes resulting from her-1(n695). All the suppressor mutations are semidominant: about 40% of n695 sup V/n695 + XX animals are wildtype hermaphrodites while about 5% of sup III/+; n695 XX animals are wild-type hermaphrodites. None of the suppressor mutations appears to exhibit any phenotype by itself in either XX or XO animals. As a first step toward determining where in the sex- determination pathway these suppressor mutations act, we have constructed double mutants between each of the suppressor mutations and the null mutations tra-1(e1099) and tra-2(e1095)). In all cases, the sup;tra XX double mutant animals appear to be identical to the tra XX single mutants. This is true both for the soma (as assayed by general body features and male tail structures) and for the germline ( as assayed by gonad morphology and the production of mature sperm). These results suggest that the suppressor mutations effect their suppression of the her-1 semidominant allele by acting upstream of tra- 2.