Fig. 2.
Maternal expression of Capr is required for the MBT. (A) Structure of Drosophila Capr showing start (ATG) and stop (TGA) codons, introns (thin lines), exons (gray boxes) and untranslated regions (light gray boxes). The P element transposon (EY06062) was excised to generate four deletion alleles. Black bars (1-4) indicate the deleted regions, none of which removes the 3′ end of the upstream gene (TAG stop codon). (B) Immunoblots with equal amounts of adult extracts were probed for CAPR or Tubulin. +, wild type; Df, Df(3L)Cat (which removes Capr); EY, transposon insertion EY06062; 1-4, Capr alleles. (C) Frames from representative DIC movies of single embryos from females of the genotypes indicated. Caprrvt is a perfect excision of EY06062, with no detectable phenotype. Frames show a sagittal portion of each embryo at times (in minutes) relative to NC14 onset; the number of embryos displaying the phenotype over the total period analyzed is indicated (n). Arrowheads indicate the furrow front. The asterisk indicates premature mitosis 14 with furrow disassembly.