RRC ID 46694
Author Yang Y, Han SM, Miller MA.
Title MSP hormonal control of the oocyte MAP kinase cascade and reactive oxygen species signaling.
Journal Dev. Biol.
Abstract The MSP domain is a conserved immunoglobulin-like structure that is important for C. elegans reproduction and human motor neuron survival. C. elegans MSPs are the most abundant proteins in sperm, where they function as intracellular cytoskeletal proteins and secreted hormones. Secreted MSPs bind to multiple receptors on oocyte and ovarian sheath cell surfaces to induce oocyte maturation and sheath contraction. MSP binding stimulates oocyte MPK-1 ERK MAP Kinase (MAPK) phosphorylation, but the function and mechanism are not well understood. Here we show that the Shp class protein-tyrosine phosphatase PTP-2 acts in oocytes downstream of sheath/oocyte gap junctions to promote MSP-induced MPK-1 phosphorylation. PTP-2 functions in the oocyte cytoplasm, not at the cell surface to inhibit multiple RasGAPs, resulting in sustained Ras activation. We also provide evidence that MSP promotes production of reactive oxygen species (ROS), which act as second messengers to augment MPK-1 phosphorylation. The Cu/Zn superoxide dismutase SOD-1, an enzyme that catalyzes ROS breakdown in the cytoplasm, inhibits MPK-1 phosphorylation downstream of or in parallel to ptp-2. Our results support the model that MSP triggers PTP-2/Ras activation and ROS production to stimulate MPK-1 activity essential for oocyte maturation. We propose that secreted MSP domains and Cu/Zn superoxide dismutases function antagonistically to control ROS and MAPK signaling.
Volume 342(1)
Pages 96-107
Published 2010-6-1
DOI 10.1016/j.ydbio.2010.03.026
PII S0012-1606(10)00209-5
PMID 20380830
PMC PMC4077032
MeSH Animals Caenorhabditis elegans / cytology Caenorhabditis elegans / metabolism Helminth Proteins / metabolism Helminth Proteins / physiology* Humans MAP Kinase Signaling System / physiology* Male Mitogen-Activated Protein Kinases / metabolism Oocytes / cytology Oocytes / metabolism Oocytes / physiology* Reactive Oxygen Species / metabolism* Signal Transduction / physiology*
IF 2.936
Times Cited 11
C.elegans tm748 tm1661 tm776