A Su(var)3-7 cDNA corresponding to the alternative transcript with the shorter 3' untranslated region is expressed under the control of an Hsp70 promoter.
Enhances the variegation at the w locus caused by In(1)wm4h, even in the absence of heat shock. Two copies of Su(var)3-7hs.PCb enhance variegation more than one copy, and the effect is stronger in males.