The C. elegans spe-9 gene encodes a sperm transmembrane protein that contains EGF-like repeats and is required for fertilization.
In the nematode worm C. elegans, individuals with mutations in the spe-9 gene produce spermatozoa with wild-type morphology and motility that cannot fertilize oocytes even after contact between gametes. Therefore, disruption of spe-9 function affects either gamete recognition, adhesion, signaling, and/or fusion. The spe-9 gene encodes a sperm transmembrane protein with an extracellular domain that contains ten epidermal growth factor-like repeats. A common feature of proteins that include epidermal growth factor-like motifs is their involvement in extracellular functions such as adhesive and ligand-receptor interactions. Additionally, the overall structure of the predicted SPE-9 protein is similar to that of ligands for the Notch/LIN-12/GLP-1 family of transmembrane receptors. These results suggest that SPE-9 functions in the specialized cell-cell interactions required for fertilization.
Singson
A
A
Department of Biology, Emory University, Atlanta, Georgia 30322, USA.
Mercer
K B
KB
L'Hernault
S W
SW
D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins; D003001:Cloning, Molecular; D012734:Disorders of Sex Development; D004815:Epidermal Growth Factor / Q000737:chemistry; D005260:Female; D005306:Fertilization / Q000502:physiology*; D017238:Genes, Helminth; D005854:Germ Cells / Q000502:physiology; D008297:Male; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D008969:Molecular Sequence Data; D010060:Ovulation; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry; D013081:Sperm Motility; D013084:Sperm-Ovum Interactions / Q000502:physiology; D013094:Spermatozoa / Q000502:physiology*
D029742:Caenorhabditis elegans Proteins; D008565:Membrane Proteins; D011994:Recombinant Proteins; C111623:Spe-9 protein, C elegans; D004815:Epidermal Growth Factor