title: A spindle-independent cleavage pathway controls germ cell formation in Drosophila.
abstract: The primordial germ cells (PGCs) are the first cells to form during Drosophila melanogaster embryogenesis. Whereas the process of somatic cell formation has been studied in detail, the mechanics of PGC formation are poorly understood. Here, using four-dimensional multi-photon imaging combined with genetic and pharmacological manipulations, we find that PGC formation requires an anaphase spindle-independent cleavage pathway. In addition to using core regulators of cleavage, including the small GTPase RhoA (Drosophila rho1) and the Rho-associated kinase, ROCK (Drosophila drok), we show that this pathway requires Germ cell-less (GCL), a conserved BTB-domain protein not previously implicated in cleavage mechanics. This alternative form of cell formation suggests that organisms have evolved multiple molecular strategies for regulating the cytoskeleton during cleavage.
authors.affiliation: HHMI and Kimmel Center for Biology and Medicine at the Skirball Institute, Department of Cell Biology, New York University School of Medicine, New York, New York 10016, USA.
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Cinalli
authors.forename: Ruth
authors.initials: R
authors.lastname: Lehmann
mesh_terms: D000818:Animals; D029721:Drosophila Proteins / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000166:cytology* / Q000378:metabolism; D004625:Embryo, Nonmammalian / Q000166:cytology* / Q000378:metabolism; D047108:Embryonic Development / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D005854:Germ Cells / Q000166:cytology* / Q000378:metabolism; D036641:Microscopy, Fluorescence, Multiphoton; D008941:Spindle Apparatus / Q000378:metabolism*; D059008:Time-Lapse Imaging; D020741:rho GTP-Binding Proteins / Q000378:metabolism*; D054460:rho-Associated Kinases / Q000378:metabolism*
chemical_list: D029721:Drosophila Proteins; D054460:rho-Associated Kinases; C511153:Rho1 protein, Drosophila; D020741:rho GTP-Binding Proteins