RRC ID 46014
Author Kovacevic I, Orozco JM, Cram EJ.
Title Filamin and phospholipase C-ε are required for calcium signaling in the Caenorhabditis elegans spermatheca.
Journal PLoS Genet
Abstract The Caenorhabditis elegans spermatheca is a myoepithelial tube that stores sperm and undergoes cycles of stretching and constriction as oocytes enter, are fertilized, and exit into the uterus. FLN-1/filamin, a stretch-sensitive structural and signaling scaffold, and PLC-1/phospholipase C-ε, an enzyme that generates the second messenger IP3, are required for embryos to exit normally after fertilization. Using GCaMP, a genetically encoded calcium indicator, we show that entry of an oocyte into the spermatheca initiates a distinctive series of IP3-dependent calcium oscillations that propagate across the tissue via gap junctions and lead to constriction of the spermatheca. PLC-1 is required for the calcium release mechanism triggered by oocyte entry, and FLN-1 is required for timely initiation of the calcium oscillations. INX-12, a gap junction subunit, coordinates propagation of the calcium transients across the spermatheca. Gain-of-function mutations in ITR-1/IP3R, an IP3-dependent calcium channel, and loss-of-function mutations in LFE-2, a negative regulator of IP3 signaling, increase calcium release and suppress the exit defect in filamin-deficient animals. We further demonstrate that a regulatory cassette consisting of MEL-11/myosin phosphatase and NMY-1/non-muscle myosin is required for coordinated contraction of the spermatheca. In summary, this study answers long-standing questions concerning calcium signaling dynamics in the C. elegans spermatheca and suggests FLN-1 is needed in response to oocyte entry to trigger calcium release and coordinated contraction of the spermathecal tissue.
Volume 9(5)
Pages e1003510
Published 2013-5-1
DOI 10.1371/journal.pgen.1003510
PMID 23671426
PMC PMC3650001
MeSH Animals Caenorhabditis elegans / genetics Caenorhabditis elegans / growth & development Calcium / metabolism* Calcium Signaling / genetics* Calcium Signaling / physiology Contractile Proteins / genetics* Contractile Proteins / metabolism Female Filamins Inositol 1,4,5-Trisphosphate / genetics Inositol 1,4,5-Trisphosphate / metabolism Male Microfilament Proteins / genetics* Microfilament Proteins / metabolism Oocytes / metabolism Oocytes / physiology Phosphoinositide Phospholipase C / genetics* Phosphoinositide Phospholipase C / metabolism Spermatozoa / metabolism Spermatozoa / physiology
IF 5.175
Times Cited 25
C.elegans tm545