Heterozygous Pc15 mutant flies exhibit ectopic sex combs at low frequency.
Homozygous germline clones do not result in female sterility or obvious defects in the oocyte.
Eye discs composed mainly of homozygous cells have a tumour phenotype.
Approximately 90% of Pc15 heterozygotes have extra sex combs.
82% of heterozygous males have ectopic sex combs on either the second or third leg.
Eye discs composed predominantly of homozygous cells (generated using the FLP/cell-lethal method) are overgrown. The mutant tissue shows defects in terminal differentiation and has defective epithelial organisation.
Homozygous neuroblast clones in the third larval instar central brain and ventral ganglion are dramatically reduced in size compared to control clones and show a dramatic reduction in mitotic activity.
Homozygous neuroblast clones examined at the late third larval stage generally still contain neuroblasts (88% of clones) if examined 24 hours after clone induction, but neuroblasts are generally absent in the clones (89% of clones) 72 hours after clone induction. 59% of the mutant clones contain neuroblasts 48 hours after clone induction.
Single cell class IV dendrite arborisation (da) neuron clones that are homozygous for Pc15 show a range of dendritic defects in the third instar larva. Homozygous class IV ddaC clones show a significant reduction in dendrite branching and total dendritic length compared to controls. Analysis of mutant clones from 72 to 96 hours after egg laying (AEL) shows that mutant clones show extensive growth of major dendritic branches and some terminal branches. However, roughly a quarter of the terminal dendrites are lost in the mutant clones during this time period. Fewer terminal branching/branch growth events are seen in the mutant clones than the control clones.
Axons of mutant single cell ddaC neuron clones occupy a similar fascicular position in the ventral nerve cord and show very similar arborisation patterns as wild-type controls. Axon terminals of mutant v'ada or vdab clones are also indistinguishable from wild type.
Heterozygotes show a partial transformation of wing to haltere.
Pc15 embryos from hetrozygous mothers show segregation defects in anaphase and telophase as judged by the presence of chromatin bridges. Most of these chromatin bridges are probably resolved because large irregularly-shaped nuclei and polyploid nuclei are only seen at a low penetrance. Pc15 embryos also show a higher level of "nuclear fallout", a process that removes nuclei with abnormal mitoses, than wild-type embryos. Fallout nuclei tend to be observed in pairs or clusters and have a late telophase appearance. There is no evidence of metaphase defects in these embryos.
Pc15 mushroom body clones show over-elaborated dendrites, but do not show similar axonal defects.
Ectopic male-specific somatic gonadal precursor (msSGP) cells are seen in both male and female Pc3/Pc15 embryos before gonad coalescence. Normal and ectopic non-sexually dimorphic somatic gonadal precursor cell (SGP) specification is also seen in these mutant embryos. At later stage in mutant male embryos, a large number of ectopic msSGPs associate with SGPs and germ cells to form a gonad. However, in most mutant female embryos msSGPs are no longer seen at later stages.
Pc15/Df(3R)ry27 mutant flies exhibit a slightly higher than wild-type average number of legs with sex combs, with a statistically insignificant average of 2.1 legs with sex combs, compared to 2.0 in Pc15/+ heterozygotes.
Pc15/Df(3R)ry619 mutant flies exhibit a higher than wild-type average number of legs with sex combs, with a statistically significant average of 2.2 legs with sex combs, compared to 2.0 in Pc15/Tp(3;3)MRS heterozygotes.
Pc15/+ animals exhibit extra sex combs on the metathoracic leg, they also have a mild transformation of the fourth abdominal segment into the fifth - patches of pigmentation are seen in the anterior part of A4.
Heterozygous males have ectopic sex combs on the second leg.
Segments of homozygous larvae are transformed so they mostly represent the eighth abdominal segment and the larvae show severe head defects.
Partial transformations of second and third legs into first legs in Pc/+ heterozygotes.
The loss of the zygotic Pc causes a severe transformation of most segments towards parasegment 8 (Lewis, Nature 276: 565-570, Duncan, Developmental Order, pp 533--554, New York).