Program of the 2004 East Coast Worm Meeting - Caenorhabditis ...

5. The spe-38 gene encodes a novel tetraspan integral membrane protein and is required
for sperm function at fertilization.
Indrani Chatterjee, Andrew W Singson
Waksman Instiute, Rutgers University, Piscataway, NJ 08854
Fertilization involves the union of haploid gametes; a sperm and an oocyte to give rise to a
diploid zygote. C.elegans serves as an excellent model system to identify and study genes that
are required for the process of fertilization. Mutations in the spe-38 gene result in both male and
hermaphrodite sterility due to a sperm specific defect. Sperm produced by spe-38 mutants are
morphologically identical to wild type sperm. They have normal motility and can make contact
with oocytes without fertilizing them. spe-38 sperm can also stimulate ovulation and can indulge
in sperm competition. We cloned the spe-38 gene in order to determine its molecular function in
fertilization. The spe-38 gene encodes a novel tetraspan integral membrane protein. Other
structurally similar tetraspan molecules have been implicated in processes such as gamete
adhesion/fusion in mammals, membrane adhesion/fusion during yeast mating, and the formation
of tight-junctions in metazoa. This suggests that SPE-38 is required for gamete adhesion and/or
fusion at fertilization. The ongoing characterization of SPE-38 will lead to a better understanding
of C. elegans fertilization and complement work in other organism.