Studies on the female-sterile phenotype of 1(1)su(f)
ts76a, a temperature-sensitive allele of the suppressor of forked mutation in Drosophila melanogaster
A new allele of the suppressor of forked [su(f)] mutation in Drosophila melanogaster has been found and designated 1(1)su(f)ts76a. It is temperature-sensitive for suppression of forked (f) and has additional temperature-sensitive phenotypes of lethality, female sterility, and abnormal bristle formation at 29 °C. It closely resembles two other conditional alleles of su(f), 1(1)su(f)ts67g and 1(1)ts726. Female sterility at 29 °C is characterized by both disorganized egg chambers in the ovarioles and also chorion-deficient oocytes. Both of these abnormalities may be the result of premature follicle cell death. The observations on 1(1)su(f)ts76a are consistent with the proposal that the similar allele, 1(1)ts726, is a cell-lethal mutation specifically affecting mitotically active cells.