Two days after induction of ectopic expression of hhαTub84B.PB in the ovary, long, stalk-like structures, which do not contain differentiated polar cells or stalk cells are seen. Three days after hhαTub84B.PB induction, ectopic polar cells and stalk cells are seen in egg chambers. The oocyte has an anterior-posterior axis defect; the migration of the oocyte nucleus from a posterior to a dorsal-anterior location does not occur. The oocyte microtubule network is defective.
Clones expressing hhαTub84B.PB in the male external genitalia cause duplications of bristles. The penis apparatus shows duplication of various structures. Clones in the anal plates have wild-type bristles but induce wild-type cells to form pattern duplication. Two types of clone are seen in the vaginal plates; in the first type the thorn bristles which stand in a row all along the vaginal plate are absent. In the second type there is duplication of both spine and long bristles in the opposite direction.
A hhts2 animal can have large clones of hhαTub84B.PB (i.e. hh+) at low frequency (by a mild heat shock of hhScer\FRT.Rnor\CD2.αTub84B flies carrying Scer\GAL4hs.PB). Shift to restrictive temperature at 84hr AEL arrests morphogenetic furrow progression; only a few retinal axons enter the lamina target field. When such axons enter a hh+ field only those LPCs in the vicinity of the axons show neuronal differentiation.
Clones expressing hhαTub84B.PB in the anterior compartment of the abdominal tergite produce ectopic intersegmental membrane (ISM), posterior hairy zone (PHZ) and posterior tergite structures. The posterior tergite structures are produced by cells outside the clone, indicating that hh functions non-autonomously. Clones in the middle region of the tergite (anterior to the pigment band) induce concentric patterns consisting of a patch of PHZ cuticle surrounded by posterior tergite structures. Trichomes and bristles within these areas are oriented radially towards the centre of the patch. More anterior clones are polarised in their effects, and induce ectopic posterior tergite structures only at their posterior edges. Anterior clones also induce PHZ and ISM. The PHZ always has reversed polarity and is located posterior to the ISM, with the boundary between the two types of structure being perpendicular to the anterior-posterior axis of the segment. Clones in the posterior tergite are rare, although a few patches of PHZ associated with ectopic macrochaetae are seen. These structures have normal polarity.
Clones expressing hhαTub84B.PB in the wing are always surrounded by vein 3 tissue. Clones in the scutum and prescutum do not survive, although before they die they cause growth and pattern alterations. Clones in the scutellum survive and form ectopic bristles.
Clones in the male external terminalia causes duplication of the anal plate and the apodeme.
Anterior compartment clones in the adult abdomen close to the anterior/posterior compartment boundary develop normally. Clones found more anteriorly within the anterior compartment, where the cuticle is normally lightly pigmented with hairs and bristles of moderate size, develop cuticle characteristic of a more posterior position within the anterior compartment, cause surrounding wild-type tissue to develop cuticle characteristic of a more posterior position within the anterior compartment, and cause abnormal bristle polarity in lateral and posterior wild-type cells surrounding the clone. Clones in the most anterior portion of the anterior compartment form ectopic posterior compartment tissue as well as anterior compartment tissue. The ectopic tissue shows a progression of anterior and posterior compartment tissue types, whose sequence, as well as the polarity of the hairs and bristles, is opposite to that of a normal segment.
In a eya1 mutant background, the lamina precursor cells complete their terminal division at the lamina furrow despite the lack of retinal axons. In an hhts2 background, hhαTub84B.PB clones induced in the eye can induce lamina precursor cell division in the brain.
Clones in the ocellar region have no phenotypic effect. Expression in the frons or orbital region causes supernumerary ocelli.
Adult clones in the eye causes disruption of the normal ommatidial array. Clones cause considerable overgrowth and deformation of the eye. Ectopic equators can be induced in the wild type tissue near the clones. The fields of ectopic ommatidia rotate coordinately creating a local equator that is separate and independent from the normal equator.
Homozygous clones exhibit gross overgrowth of the eye. External roughness of the eye spreads to genetically wild type regions.
Clones organise supernumerary double-anterior wings.
Clones in the posterior wing compartment contribute to normal patterning, those in the anterior compartment are associated with abnormal vein patterns. Clones in the posterior leg compartment are normal but clones in the anterior cause reiterations of either dorsal or ventral anterior patterns, or the formation of supernumerary legs composed of symmetric anterior compartments.