1k9c

Solution Structure of Calreticulin P-domain subdomain (residues 189-261)Solution Structure of Calreticulin P-domain subdomain (residues 189-261)

Structural highlights 1k9c is a 1 chain structure with sequence from Rattus norvegicus. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: Solution NMR Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function CALR_RAT Calcium-binding chaperone that promotes folding, oligomeric assembly and quality control in the endoplasmic reticulum (ER) via the calreticulin/calnexin cycle. This lectin interacts transiently with almost all of the monoglucosylated glycoproteins that are synthesized in the ER. Interacts with the DNA-binding domain of NR3C1 and mediates its nuclear export. Involved in maternal gene expression regulation. May participate in oocyte maturation via the regulation of calcium homeostasis (By similarity). Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Calreticulin (CRT) is an abundant, soluble molecular chaperone of the endoplasmic reticulum. Similar to its membrane-bound homolog calnexin (CNX), it is a lectin that promotes the folding of proteins carrying N-linked glycans. Both proteins cooperate with an associated co-chaperone, the thiol-disulfide oxidoreductase ERp57. This enzyme catalyzes the formation of disulfide bonds in CNX and CRT-bound glycoprotein substrates. Previously, we solved the NMR structure of the central proline-rich P-domain of CRT comprising residues 189-288. This structure shows an extended hairpin topology, with three short anti-parallel beta-sheets, three small hydrophobic clusters, and one helical turn at the tip of the hairpin. We further demonstrated that the residues 225-251 at the tip of the CRT P-domain are involved in direct contacts with ERp57. Here, we show that the CRT P-domain fragment CRT(221-256) constitutes an autonomous folding unit, and has a structure highly similar to that of the corresponding region in CRT(189-288). Of the 36 residues present in CRT(221-256), 32 form a well-structured core, making this fragment one of the smallest known natural sequences to form a stable non-helical fold in the absence of disulfide bonds or tightly bound metal ions. CRT(221-256) comprises all the residues of the intact P-domain that were shown to interact with ERp57. Isothermal titration microcalorimetry (ITC) now showed affinity of this fragment for ERp57 similar to that of the intact P-domain, demonstrating that CRT(221-256) may be used as a low molecular mass mimic of CRT for further investigations of the interaction with ERp57. We also solved the NMR structure of the 73-residue fragment CRT(189-261), in which the tip of the hairpin and the first beta-sheet are well structured, but the residues 189-213 are disordered, presumably due to lack of stabilizing interactions across the hairpin. NMR structures of 36 and 73-residue fragments of the calreticulin P-domain.,Ellgaard L, Bettendorff P, Braun D, Herrmann T, Fiorito F, Jelesarov I, Guntert P, Helenius A, Wuthrich K J Mol Biol. 2002 Sep 27;322(4):773-84. PMID:12270713 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Calreticulin 3D structures

spinqualitylabelsall models 1k9c Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image