The inositol 1,4,5-trisphosphate receptor (Itpr) gene family in Xenopus: identification of type 2 and type 3 inositol 1,4,5-trisphosphate receptor subtypes

摘要

pStudies in the iXenopus/i model system have provided considerable insight into the developmental role of intracellular Casup2+/sup signals produced by activation of IPsub3/subRs (inositol 1,4,5-trisphosphate receptors). However, unlike mammalian systems where three IPsub3/subR subtypes have been well characterized, our molecular understanding of the IPsub3/subRs that underpin Casup2+/sup signalling during iXenopus/i embryogenesis relate solely to the original characterization of the ‘iXenopus/i IPsub3/subR’ cloned and purified from iXenopus laevis/i oocytes several years ago. In the present study, we have identified iXenopus/i type 2 and type 3 IPsub3/subRs and report the full-length sequence, genomic architecture and developmental expression profile of these additional IPsub3/subR subtypes. In the light of the emerging genomic resources and opportunities for genetic manipulation in the diploid frog iXenopus tropicalis/i, these data will facilitate manipulations to resolve the contribution of IPsub3/subR diversity in Casup2+/sup signalling events observed during vertebrate development./p