Maternal effect mutations of the sponge locus affect actin cytoskeletal rearrangements in Drosophila melanogaster embryos

M. A. Postner, K. G. Miller, E. F. Wieschaus

Research output: Contribution to journalArticle

46 Scopus citations

Abstract

In the syncytial blastoderm stage of Drosophila embryogenesis, dome-shaped actin 'caps' are observed above the interphase nuclei. During mitosis, this actin rearranges to participate in the formation of pseudocleavage furrows, transient membranous invaginations between dividing nuclei. Embryos laid by homozygous sponge mothers lack these characteristic actin structures, but retain other actin associated structures and processes. Our results indicate that the sponge product is specifically required for the formation of actin caps and metaphase furrows. The specificity of the sponge phenotype permits dissection of both the process of actin cap formation and the functions of actin caps and metaphase furrows. Our data demonstrate that the distribution of actin binding protein 13D2 is unaffected in sponge embryos and suggest that 13D2 is upstream of actin in cortical cap assembly. Although actin caps and metaphase furrows have been implicated in maintaining the fidelity of nuclear division and the positions of nuclei within the cortex, our observations indicate that these structures are dispensible during the early syncytial blastoderm cell cycles. A later requirement for actin metaphase furrows in preventing the nucleation of mitotic spindles between inappropriate centrosomes is observed. Furthermore, the formation of actin caps and metaphase furrows is not a prerequisite for the formation of the hexagonal array of actin instrumental in the conversion of the syncytial embryo into a cellular blastoderm.

Original languageEnglish (US)
Pages (from-to)1205-1218
Number of pages14
JournalJournal of Cell Biology
Volume119
Issue number5
DOIs
StatePublished - Dec 14 1992

All Science Journal Classification (ASJC) codes

  • Cell Biology

Fingerprint Dive into the research topics of 'Maternal effect mutations of the sponge locus affect actin cytoskeletal rearrangements in Drosophila melanogaster embryos'. Together they form a unique fingerprint.

  • Cite this