The majority of eggs produced by homozygous females have fused, reduced or no chorionic dorsal appendages. 41% of these eggs are cup-shaped, 42% have a reduced anterior/posterior (A/P) axis, 13% have abnormal dorsal appendages but length along the A/P axis is relatively normal and 4% are similar to wild-type. Approximately half the eggs laid by homozygous females are fertilised and resume meiosis as they are laid. The spindle apparatus and chromosome organisation appear similar to wild-type. Eggs are irregular in shape and smaller than wild-type. A small fraction of egg chambers have an abnormal number of nurse cells or show a bicaudal-like phenotype. Follicle cell movements and oocyte growth rate are altered compared to wild-type. Testes from homozygous pupae and adults are 2 to 3 times smaller than wild-type. Only primary spermatocytes and cyst cells are seen in most testes, and meiotic figures are never seen. Some cysts contain fewer than the normal number of 16 spermatocytes. As in wild-type, centrioles duplicate at the beginning of the spermatocyte growth phase and are associated with two small asters. At the end of prophase, centrioles elongate at least threefold and become associated with large asters, as in wild-type. Meiotic spindles do not form. Although meiotic divisions do not occur, other aspects of spermiogenesis continue; in older cysts the germ cell microtubule cytoskeleton appears to have undergone spatial reorganisation - microtubules are elongated and arranged in circular bundles that form a dense shell below the plasma membrane of round germ cells containing one or two chromatin masses. Small anucleate cytoplasmic fragments surrounded by microtubule shells are also seen. Irregular axonemes are sometimes present. The nuclear membrane of homozygous spermatocytes form small evaginations, probably due to the nuclear envelope bulging out near nuclear pores.

Nup154^tlp1, cup²¹ has ovariole phenotype