Imprecise excision of the P{lacW}Nnp-1k07826 element, which removes the element and 1.6kb of sequences downstream. This deletion extends through the transcription and translation start sites of Tap42 and removes the first 8 codons of the Tap42 coding region.
Tap42Δ305b animals (Df(2L)Tap42Δ305b homozygotes in which lack of Nnp-1 and CG6523 function has been rescued using the P{Nnp-1t5.1} transgene) progress to the early third larval instar with a slight developmental delay and die shortly thereafter, between 96 and 120 hours after egg laying. Tap42Δ305b larvae (Df(2L)Tap42Δ305b homozygotes in which lack of Nnp-1 and CG6523 function has been rescued using the P{Nnp-1t5.1} transgene) have smaller and poorly organised mitotic spindles in the central nervous system compared to controls and most mitotic chromosomes are in a highly condensed metaphase configuration (no mitotic cells in anaphase or telophase have been observed). Third larval instar mutant brains contain pyknotic nuclei. Clones of cells lacking Tap42 function (homozygous for Df(2L)Tap42Δ305b, and with lack of Nnp-1 and CG6523 function rescued by the P{Nnp-1t5.1} transgene) show no change in cell size compared to control cells, and the cell cycle phasing of the mutant cells is indistinguishable from that of wild-type controls. Although clones of cells lacking Tap42 function (homozygous for Df(2L)Tap42Δ305b, and with lack of Nnp-1 and CG6523 function rescued by the P{Nnp-1t5.1} transgene) can be readily identified in wing discs 48 hours after induction, by 72 hours after induction they are no longer present. Mutant clones induced using the Minute technique can persist to 72 hours, but show signs of massive cell death, with highly condensed pyknotic nuclei, and these clones are eliminated at later timepoints. Mutant clones in the eye imaginal discs can survive beyond the 72 hour period in the mitotically quiescent region posterior to the morphogenetic furrow, but not in the mitotically active anterior region.
Tap42Δ305b is a non-suppressor of increased cell size phenotype of Ptendj189
Tap42Δ305b/Df(2L)Tap42Δ305b, Nnp-1t5.1 has wing disc | third instar larval stage phenotype
Clones of Ptendj189 Tap42Δ305b double mutant cells (homozygous for Ptendj189 and Df(2L)Tap42Δ305b and with the lack of Nnp-1 and CG6523 function caused by Df(2L)Tap42Δ305b rescued using the P{Nnp-1t5.1} transgene) show the characteristic increase in cell size and S/G2 content of Ptendj189 single mutants.
Tap42Δ305b is rescued by Scer\GAL4Tub.PU/Tap42UAS.cCa