1N4K

Crystal structure of the inositol 1,4,5-trisphosphate receptor binding core in complex with IP3

Summary for 1N4K

• Entry DOI: 10.2210/pdb1n4k/pdb
• Descriptor: Inositol 1,4,5-trisphosphate receptor type 1, D-MYO-INOSITOL-1,4,5-TRIPHOSPHATE (3 entities in total)
• Functional Keywords: ip3 receptor, ip3-binding core, calcium channel, protein-ligand complex, b-trefoil fold, armadillo-like fold, membrane protein
• Biological source: Mus musculus (house mouse)
• Cellular location: Endoplasmic reticulum membrane; Multi-pass membrane protein: P11881
• Total number of polymer chains: 1
• Total formula weight: 44023.37

Authors

Bosanac, I.,Alattia, J.R.,Mal, T.K.,Chan, J.,Talarico, S.,Tong, F.K.,Tong, K.I.,Yoshikawa, F.,Furuichi, T.,Iwai, M.,Michikawa, T.,Mikoshiba, K.,Ikura, M. (deposition date: 2002-10-31, release date: 2002-12-25, Last modification date: 2024-02-14)

Primary citation

Bosanac, I.,Alattia, J.R.,Mal, T.K.,Chan, J.,Talarico, S.,Tong, F.K.,Tong, K.I.,Yoshikawa, F.,Furuichi, T.,Iwai, M.,Michikawa, T.,Mikoshiba, K.,Ikura, M.
Structure of the inositol 1,4,5-trisphosphate receptor binding core in complex with its ligand.
Nature, 420:696-700, 2002

PubMed Abstract: In a variety of cells, the Ca2+ signalling process is mediated by the endoplasmic-reticulum-membrane-associated Ca2+ release channel, inositol 1,4,5-trisphosphate (InsP3) receptor (InsP3R). Being ubiquitous and present in organisms ranging from humans to Caenorhabditis elegans, InsP3R has a vital role in the control of cellular and physiological processes as diverse as cell division, cell proliferation, apoptosis, fertilization, development, behaviour, memory and learning. Mouse type I InsP3R (InsP3R1), found in high abundance in cerebellar Purkinje cells, is a polypeptide with three major functionally distinct regions: the amino-terminal InsP3-binding region, the central modulatory region and the carboxy-terminal channel region. Here we present a 2.2-A crystal structure of the InsP3-binding core of mouse InsP3R1 in complex with InsP3. The asymmetric, boomerang-like structure consists of an N-terminal beta-trefoil domain and a C-terminal alpha-helical domain containing an 'armadillo repeat'-like fold. The cleft formed by the two domains exposes a cluster of arginine and lysine residues that coordinate the three phosphoryl groups of InsP3. Putative Ca2+-binding sites are identified in two separate locations within the InsP3-binding core.

PubMed: 12442173
DOI: 10.1038/nature01268

Experimental method

X-RAY DIFFRACTION (2.2 Å)