RRC ID 19707
Author Yamaguchi A, Saito T, Yamada L, Taniguchi H, Harada Y, Sawada H.
Title Identification and localization of the sperm CRISP family protein CiUrabin involved in gamete interaction in the ascidian Ciona intestinalis.
Journal Mol Reprod Dev
Abstract Ascidians are hermaphrodites, and most release sperm and eggs nearly simultaneously. Many species, including Halocynthia roretzi and Ciona intestinalis, are self-sterile. We previously reported that the interaction between a 12 EGF-like repeat-containing vitelline-coat (VC) protein, HrVC70, and a sperm GPI-anchored CRISP, HrUrabin, in lipid rafts plays a key role in self-/nonself-recognizable gamete interaction in H. roretzi. On the other hand, we recently identified two pairs of polymorphic genes responsible for self-incompatibility in C. intestinalis by positional cloning: The sperm polycystin 1-like receptors s-Themis-A/B and its fibrinogen-like ligand v-Themis-A/B on the VC. However, it is not known if the orthologs of HrVC70 and HrUrabin also participate in gamete interaction in C. intestinalis since they are from different orders. Here, we tested for a C. intestinalis ortholog (CiUrabin) of HrUrabin by searching the genome database and proteomes of sperm lipid rafts. The identified CiUrabin belongs to the CRISP family, with a PR domain and a GPI-anchor-attachment site. CiUrabin appears to be specifically expressed in the testis and localized at the surface of the sperm head, as revealed by Northern blotting and immunocytochemistry, respectively. The specific interaction between CiVC57, a C. intestinalis ortholog of HrVC70, and CiUrabin was confirmed by Far Western analysis, similarly to the interaction between HrVC70 and HrUrabin. The molecular interaction between CiVC57 and CiUrabin may be involved in the primary binding of sperm to the VC prior to the allorecognition process, mediated by v-Themis-A/B and s-Themis-A/B, during fertilization of C. intestinalis.
Volume 78(7)
Pages 488-97
Published 2011-7-1
DOI 10.1002/mrd.21329
PMID 21656869
MeSH Amino Acid Sequence Animals Blotting, Western Ciona intestinalis / genetics Ciona intestinalis / metabolism* Egg Proteins / metabolism Fertilization Hermaphroditic Organisms / genetics Hermaphroditic Organisms / metabolism Humans Male Membrane Glycoproteins / chemistry Membrane Glycoproteins / genetics Membrane Glycoproteins / metabolism* Molecular Sequence Data Organ Specificity Phylogeny Sequence Alignment Spermatozoa / chemistry* Testis / chemistry Testis / metabolism Ultracentrifugation Vitelline Membrane / metabolism
IF 2.823
Times Cited 12
C.intestinalis / (O.japonicus) Wild C. int