A 4,064 nt deletion.
Df(3R)hpRNA:1 mutant flies are lethal, but combination with either P{hpRNA:1+t8.6} or P{hpRNA:1-t7.9} (lacking a short region containing the hpRNA:1 gene) restores their viability. Flies carrying Df(3R)hpRNA:1 deletion together with the P{hpRNA:1-t7.9} construct, the ' hpRNA:1 mutant' combination, in trans to Df(3R)ED6025 show significantly reduced male fertility as well as decreased numbers of mature sperm in their seminal vesicles compared to their ' hpRNA:1 rescue' counterparts (carrying Df(3R)hpRNA:1 combined with P{hpRNA:1+t8.6}) and wild-type controls. The nuclear alignment as well as the investment cone alignment is perturbed in the hpRNA:1 mutant/Df(3R)ED6025 spermatocytes (and restored in the rescue males).