The C terminus from amino acid 760 to 1039 has been deleted.
There is a significant loss of male viability (about 2/5 of expected males survive) in homozygous mutants where expression of msl-1Δ84C.hs in induced by heatshock.
msl-1Δ84C.hs has phenotype, suppressible by msl-2Hsp83.PK
The addition of msl-2Hsp83.PK suppresses the male viability phenotype seen in heatshocked msl-1Δ84C.hs flies.