Suppressor of repeat-induced silencing, as seen at heterochromatic tandem arrays of insertions of the P{lacW} transposon.

Nuage particles are lost in spn-E¹/spn-E^hls-03987 nurse cells and the perinuclear nuage is smoother than normal.

Homozygotes and trans-heterozygotes with spn-E¹ show an increased rate of non-disjunction in all except the small 4th chromosome. There are also substantial biases in recovery of reciprocal sperm classes. Nullo-XY sperm are recovered in considerable excess over the reciprocal XY sperm class. Also a weaker bias in favour of normal X-bearing sperm is seen.

Females lay few eggs and they appear to be unfertilised. Oocyte is not located at the usual posterior position within the egg, 95% of late stage egg chambers were ventralised and a small number of the egg chambers are degenerating. Heterozygotes with Df(3R)sbd105 (spn-E^-) exhibit mislocalised oocyte phenotype and degenerating egg chambers. Microtubule structure is disrupted in the egg chambers due to the inappropriate formation of an extensive microtubule meshwork during stage 8 to 9 (not premature cytoplasmic streaming).

10% of eggs fail to localise the oocyte to the posterior of the egg chamber, 95% eggs have variable fused filaments.

Affects the early anteroposterior process in oogenesis. 5-10% of stage 2 to 10 eggs produced by homozygous female have mislocalised oocytes. 95% late stage egg chambers have a ventralised phenotype with only one respiratory appendage on the dorsal midline or two shortened appendages. No eggs hatch.

female-sterile 10% of eggs fail to localize oocyte to posterior of egg chamber; 95% of eggs have variable fused filaments.