In homozygous clones in the leg that span a joint, the homozygous cells do not form any joint tissue, although wild-type cells that are in contact with the clone can form joint structures, resulting in incomplete joints. The effect of the Nl1N-3 mutation on joint formation appears to be autonomous. Clones in the anterior-ventral compartment of the femur and tibia interfere with the separation between the distal femur and the proximal tibia. Legs carrying large anterior or posterior clones are shorter than their wild-type counterparts, and mosaic tarsal segments have a 25% reduction in area and a 30% reduction in length compared to wild-type controls. Clones restricted to one leg segment do not affect the size of this segment or the overall morphology and size of the leg.
Heterozygotes appear wild-type.
Homozygous clones on the ventral surface of the wing abutting the wing margin cause extensive scalloping, dorsal clones differentiate a normal margin. Mosaic wings also exhibit altered spacing between the veins.
Homozygous lethal at 29oC. Homozygotes do not reach the late pupal stage. 14% of Nl1N-3/Nl1N-ts1 flies survive at 29oC. Phenotypes seen include fused stubby legs, a small head and small, rough eyes. 29% of Nl1N-3/NAx-tsl flies survive at 29oC. Phenotypes seen include small eyes and head, an abruptex phenotype and stubby legs.
Nl1N-3/+ females are wild type; Nl1N-3/N females and Nl1N-3/Y males are lethal. Heterozygotes with fa and Nfa-g are fa-like; with nd, they have nd-like wings and small eyes; with Nnd-3, they are viable, fertile and Nnd-3-like. Developmental defects in Nl1N-3/Y males and time of lethal effect same as in Nl1N-1/Y. Some Nl1N-3/Nl1N-ts1 females survive to late pupal stage (Shellenbarger and Mohler, 1975).
Df(3R)Delta-FX3, Nl1N-3 has visible | dominant phenotype
Nl1N-3, wgS107 has adult thoracic sensillum phenotype
Df(3R)Delta-FX3, Nl1N-3 has adult thoracic sensillum phenotype
Nl1N-3 ; wgS107 double heterozygotes have a reduced number of thoracic bristles compared to wild-type. Nl1N-3 ; Df(3R)Dl-FX3 double heterozygotes have an increased number of thoracic bristles compared to wild-type.
Abrahamson.
Intragenic recombination experiments indicate that the proximal frameshift lesion in Nl1N-3 is associated with pupal lethality and a dominant loss of microchaetae phenotype, while the distal regulatory lesion is associated with embryonic neurogenic lethality and acts as an intragenic suppressor of the dominant loss of microchaetae phenotype caused by the proximal lesion.