Premium
drop out : A third chromosome maternal‐effect locus required for formation of the Drosophila cellular blastoderm
Author(s) -
Galewsky Samuel,
Schulz Robert A.
Publication year - 1992
Publication title -
molecular reproduction and development
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.745
H-Index - 105
eISSN - 1098-2795
pISSN - 1040-452X
DOI - 10.1002/mrd.1080320405
Subject(s) - blastoderm , biology , cytoplasm , mutant , microbiology and biotechnology , somatic cell , genetics , embryo , locus (genetics) , population , polytene chromosome , drosophilidae , gene , drosophila melanogaster , embryogenesis , demography , sociology
drop out (dop) is a recessive maternal‐effect locus identified in a screen for female‐sterile mutations in Drosophila polytene region 71C‐F. Phenotypic analyses of the dop mutation indicate that the gene is required for proper formation of the cellular blastoderm. In embryos derived from either homozygous or hemizygous dop mothers, cytoplasmic clearing, nuclear migration and division, and pole cell formation appear normal. However, developmental defects are observed prior to and during cellularization of the blastoderm. At the beginning of nuclear cycle 14, the distinct separation of the internal yolk mass and the cortical cytoplasm breaks down. Subsequently, a population of somatic nuclei located at the periphery of the syncytial blastoderm becomes irregularly spaced and nonuniform in their distribution. Despite a somewhat regular formation of the cortical actin network, cellularizaiton in mutant embryos is extremely variable. Such embryos fail to gastrulate normally and produce variable amounts of defective cuticle. Overall, our analyses suggest that the dop gene functions in maintaining the separation of yolk and cortical cytoplasm and in stabilizing the distribution of somatic nuclei in the Drosophila syncytial blastoderm.