title: IP(3) receptor subtype-dependent activation of store-operated calcium entry through I(CRAC).
abstract: The store-operated, calcium release-activated calcium current I(CRAC) is activated by the depletion of inositol 1,4,5-trisphosphate (IP(3))-sensitive stores. The significantly different dose-response relationships of IP(3)-mediated Ca(2+) release and CRAC channel activation indicate that I(CRAC) is activated by a functionally, and possibly physically, distinct sub-compartment of the endoplasmic reticulum (ER), the so-called CRAC store. Vertebrate genomes contain three IP(3) receptor (IP(3)R) genes and most cells express at least two subtypes, but the functional relevance of various IP(3)R subtypes with respect to store-operated Ca(2+) entry is completely unknown. We here demonstrate in avian B cells (chicken DT40) that IP(3)R type II and type III participate in IP(3)-induced activation of I(CRAC), but IP(3)R type I does not. This suggests that the expression pattern of IP(3)R contributes to the formation of specialized CRAC stores in B cells.
authors.affiliation: Center for Biomedical Research at The Queen's Medical Center and John A Burns School of Medicine at the University of Hawaii, Honolulu, HI 96813, USA.
authors.forename: Christine
authors.initials: C
authors.lastname: Peinelt
authors.forename: Andreas
authors.initials: A
authors.lastname: Beck
authors.forename: Mahealani K
authors.initials: MK
authors.lastname: Monteilh-Zoller
authors.forename: Reinhold
authors.initials: R
authors.lastname: Penner
authors.forename: Andrea
authors.initials: A
authors.lastname: Fleig
mesh_terms: D000818:Animals; D020013:Calcium Signaling / Q000187:drug effects; D002460:Cell Line; D002645:Chickens; D015544:Inositol 1,4,5-Trisphosphate / Q000494:pharmacology; D053496:Inositol 1,4,5-Trisphosphate Receptors / Q000378:metabolism*; D015640:Ion Channel Gating / Q000187:drug effects; D015759:Ionomycin / Q000494:pharmacology
chemical_list: D053496:Inositol 1,4,5-Trisphosphate Receptors; D015759:Ionomycin; D015544:Inositol 1,4,5-Trisphosphate