title: Sperm development and motility are regulated by PP1 phosphatases in Caenorhabditis elegans.
abstract: Sperm from different species have evolved distinctive motility structures, including tubulin-based flagella in mammals and major sperm protein (MSP)-based pseudopods in nematodes. Despite such divergence, we show that sperm-specific PP1 phosphatases, which are required for male fertility in mouse, function in multiple processes in the development and motility of Caenorhabditis elegans amoeboid sperm. We used live-imaging analysis to show the PP1 phosphatases GSP-3 and GSP-4 (GSP-3/4) are required to partition chromosomes during sperm meiosis. Postmeiosis, tracking fluorescently labeled sperm revealed that both male and hermaphrodite sperm lacking GSP-3/4 are immotile. Genetic and in vitro activation assays show lack of GSP-3/4 causes defects in pseudopod development and the rate of pseudopodial treadmilling. Further, GSP-3/4 are required for the localization dynamics of MSP. GSP-3/4 shift localization in concert with MSP from fibrous bodies that sequester MSP at the base of the pseudopod, where directed MSP disassembly facilitates pseudopod contraction. Consistent with a role for GSP-3/4 as a spatial regulator of MSP disassembly, MSP is mislocalized in sperm lacking GSP-3/4. Although a requirement for PP1 phosphatases in nematode and mammalian sperm suggests evolutionary conservation, we show PP1s have independently evolved sperm-specific paralogs in separate lineages. Thus PP1 phosphatases are highly adaptable and employed across a broad range of sexually reproducing species to regulate male fertility.
authors: Department of Biology, San Francisco State University, San Francisco, California 94132, USA.
authors: Jui-ching
authors: JC
authors: Wu
authors: Aiza C
authors: AC
authors: Go
authors: Mark
authors: M
authors: Samson
authors: Thais
authors: T
authors: Cintra
authors: Susan
authors: S
authors: Mirsoian
authors: Tammy F
authors: TF
authors: Wu
authors: Margaret M
authors: MM
authors: Jow
authors: Eric J
authors: EJ
authors: Routman
authors: Diana S
authors: DS
authors: Chu
mesh_terms: D000818:Animals; D005075:Biological Evolution; D017173:Caenorhabditis elegans / Q000201:enzymology* / Q000235:genetics; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism*; D020090:Chromosome Segregation / Q000502:physiology; D005298:Fertility / Q000235:genetics; D008297:Male; D008540:Meiosis / Q000502:physiology; D008954:Models, Biological; D010802:Phylogeny; D054645:Protein Phosphatase 1 / Q000235:genetics / Q000378:metabolism*; D011554:Pseudopodia / Q000235:genetics / Q000378:metabolism; D013081:Sperm Motility; D013091:Spermatogenesis / Q000235:genetics; D013094:Spermatozoa / Q000201:enzymology*
chemical_list: D029742:Caenorhabditis elegans Proteins; D054645:Protein Phosphatase 1