ipp-5 encodes a type I inositol 5-phosphatase homolog. ipp-5 acts downstream of let-23 to negatively regulate IP3 signaling and is involved in spermathecal contractions during ovulation. an ipp-5::gfp transcriptional reporter is expressed in the adult distal spermatheca and weakly in the proximal sheath in Caenorhabditis elegans