Amino acid replacement: W739R.
T23975146C
W739R | mr-PA
W739R
Same mutation as mr1. Site of nucleotide substitution in mutant inferred by FlyBase based on reported amino acid change.
nurse cell (with mr1)
nurse cell & nuclear chromosome
nurse cell & nucleus
spindle | maternal effect (with mr1)
The nurse cells revert to mitosis at stage 5 in mr1/mr2 egg chambers. Nurse cells in later mr1/mr2 egg chambers often become pycnotic. Embryos derived from mr1/mr2 egg chambers which complete oogenesis complete meiosis, however, the zygotic nuclei and frequently the polar bodies, are arrested on metaphase spindles that are anastral or have broad poles. The chromosomes are hypercondensed in these embryos.
Semi-lethal when hemizygous, with most hemizygotes dying as pharate adults. Escapers have etched tergites and very rough eyes. Nurse cells in homozygous ovaries initiate endo cycles, but later egg chambers contain condensed chromosomes in place of polyploid nurse cell nuclei. These condensed chromosomes are associated with large multipolar spindles. Ring canals are seen to degenerate shortly after the inappropriate spindles are seen. The nurse cell defects are not visible until stage 4 of egg chamber development. The follicle cell epithelium sometimes forms a double layer of cells. Homozygous or mr1/mr2 females sometimes lay eggs (which do not hatch). Fertilised eggs show an early metaphase arrest phenotype, containing usually between 6 and 10 metaphase nuclei. The spindles are broader than wild-type both at the metaphase plate and at the spindle poles. Metaphase spindles are found at the position where the polar bodies are normally located.
Less extreme than mr. Nearly wild type at 19oC. female-sterile Oogenesis normal through stage 4; then compound nurse cell chromosomes fall apart and degenerate. Karyosome of oocyte also disappears. Oogenesis does not proceed beyond sixth stage (King, 1964). RK2 at 25oC or above.
mr[+]/mr2 is a suppressor of increased cell death phenotype of shtd1
mr2, vihKG02013 has lethal | third instar larval stage phenotype
lmgA03424, mr2 has abnormal mitotic cell cycle | third instar larval stage phenotype
lmgA03424, mr2 has lethal | prepupal stage P4(ii) phenotype
lmgA03424, mr2 has increased occurrence of cell division | third instar larval stage phenotype
mr2, vihS110501 has lethal | third instar larval stage phenotype
bru1PA/bru1Z2286, mr1/mr2 has abnormal mitotic cell cycle | oogenesis stage S2 phenotype
bru1PA/bru1Z2286, mr1/mr2 has abnormal mitotic cell cycle | oogenesis stage S1 phenotype
mr1/mr2 is an enhancer of female germline stem cell phenotype of effmer1/eff8
mr[+]/mr2 is a suppressor of ommatidium phenotype of shtd1
fzrie28, mr[+]/mr2 has embryonic somatic muscle cell phenotype
fzrie28, mr[+]/mr2 has embryonic myoblast | late embryonic stage phenotype
fzrie28, mr2 has embryonic somatic muscle cell phenotype
fzrie28, mr2 has embryonic myoblast | late embryonic stage phenotype
lmgA03424, mr2 has larval brain | third instar larval stage phenotype
bru1PA/bru1Z2286, mr1/mr2 has germline cell | female | oogenesis stage S1 phenotype
bru1PA/bru1Z2286, mr1/mr2 has germline cell | female | oogenesis stage S2 phenotype
e(mr)1, mr1/mr2 has antennal lobe phenotype
mr1/mr2 is rescued by Scer\GAL4Act5C.PI/mrUASp.cKa
mr1/mr2 is rescued by Scer\GAL4VP16.nanos.UTR/mrUASp.cKa
Bridges, 24th Nov. 1925.