These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Structural studies of inositol 1,4,5-trisphosphate receptor: coupling ligand binding to channel gating.
    Author: Chan J, Yamazaki H, Ishiyama N, Seo MD, Mal TK, Michikawa T, Mikoshiba K, Ikura M.
    Journal: J Biol Chem; 2010 Nov 12; 285(46):36092-9. PubMed ID: 20843799.
    Abstract:
    The three isoforms of the inositol 1,4,5-trisphosphate receptor (IP(3)R) exhibit distinct IP(3) sensitivities and cooperativities in calcium (Ca(2+)) channel function. The determinants underlying this isoform-specific channel gating mechanism have been localized to the N-terminal suppressor region of IP(3)R. We determined the 1.9 Å crystal structure of the suppressor domain from type 3 IP(3)R (IP(3)R3(SUP), amino acids 1-224) and revealed structural features contributing to isoform-specific functionality of IP(3)R by comparing it with our previously determined structure of the type 1 suppressor domain (IP(3)R1(SUP)). The molecular surface known to associate with the ligand binding domain (amino acids 224-604) showed marked differences between IP(3)R3(SUP) and IP(3)R1(SUP). Our NMR and biochemical studies showed that three spatially clustered residues (Glu-20, Tyr-167, and Ser-217 in IP(3)R1 and Glu-19, Trp-168, and Ser-218 in IP(3)R3) within the N-terminal suppressor domains of IP(3)R1(SUP) and IP(3)R3(SUP) interact directly with their respective C-terminal fragments. Together with the accompanying paper (Yamazaki, H., Chan, J., Ikura, M., Michikawa, T., and Mikoshiba, K. (2010) J. Biol. Chem. 285, 36081-36091), we demonstrate that the single aromatic residue in this region (Tyr-167 in IP(3)R1 and Trp-168 in IP(3)R3) plays a critical role in the coupling between ligand binding and channel gating.
    [Abstract] [Full Text] [Related] [New Search]