RRC ID 32481
Author Yamamoto S, Bayat V, Bellen HJ, Tan C.
Title Protein phosphatase 1ß limits ring canal constriction during Drosophila germline cyst formation.
Journal PLoS One
Abstract Germline cyst formation is essential for the propagation of many organisms including humans and flies. The cytoplasm of germline cyst cells communicate with each other directly via large intercellular bridges called ring canals. Ring canals are often derived from arrested contractile rings during incomplete cytokinesis. However how ring canal formation, maintenance and growth are regulated remains unclear. To better understand this process, we carried out an unbiased genetic screen in Drosophila melanogaster germ cells and identified multiple alleles of flapwing (flw), a conserved serine/threonine-specific protein phosphatase. Flw had previously been reported to be unnecessary for early D. melanogaster oogenesis using a hypomorphic allele. We found that loss of Flw leads to over-constricted nascent ring canals and subsequently tiny mature ring canals, through which cytoplasmic transfer from nurse cells to the oocyte is impaired, resulting in small, non-functional eggs. Flw is expressed in germ cells undergoing incomplete cytokinesis, completely colocalized with the Drosophila myosin binding subunit of myosin phosphatase (DMYPT). This colocalization, together with genetic interaction studies, suggests that Flw functions together with DMYPT to negatively regulate myosin activity during ring canal formation. The identification of two subunits of the tripartite myosin phosphatase as the first two main players required for ring canal constriction indicates that tight regulation of myosin activity is essential for germline cyst formation and reproduction in D. melanogaster and probably other species as well.
Volume 8(7)
Pages e70502
Published 2013-7-25
DOI 10.1371/journal.pone.0070502
PII PONE-D-12-38850
PMID 23936219
PMC PMC3723691
MeSH Actin Cytoskeleton Amino Acid Sequence Animals Cell Differentiation Cell Proliferation Cytokinesis / genetics Drosophila Proteins / genetics Drosophila Proteins / metabolism* Drosophila melanogaster / cytology Drosophila melanogaster / enzymology* Drosophila melanogaster / genetics Drosophila melanogaster / growth & development Female Gene Expression Regulation, Developmental Germ Cells / cytology Germ Cells / enzymology* Male Molecular Sequence Data Myosin-Light-Chain Phosphatase / genetics Myosin-Light-Chain Phosphatase / metabolism* Myosins / genetics Myosins / metabolism* Oocytes / cytology Oocytes / enzymology* Oogenesis / genetics Phosphoprotein Phosphatases / genetics Phosphoprotein Phosphatases / metabolism* Protein Subunits / genetics Protein Subunits / metabolism*
IF 2.74
Times Cited 20
Drosophila DGRC#115159 DGRC#115284