View source for 1ixa


==THE THREE-DIMENSIONAL STRUCTURE OF THE FIRST EGF-LIKE MODULE OF HUMAN FACTOR IX: COMPARISON WITH EGF AND TGF-A==
<StructureSection load='1ixa' size='340' side='right'caption='[[1ixa]], [[NMR_Ensembles_of_Models | 1 NMR models]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1ixa]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1IXA OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1IXA FirstGlance]. <br>
</td></tr><tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1ixa FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1ixa OCA], [http://pdbe.org/1ixa PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1ixa RCSB], [http://www.ebi.ac.uk/pdbsum/1ixa PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1ixa ProSAT]</span></td></tr>
</table>
== Disease ==
[[http://www.uniprot.org/uniprot/FA9_HUMAN FA9_HUMAN]] Defects in F9 are the cause of recessive X-linked hemophilia B (HEMB) [MIM:[http://omim.org/entry/306900 306900]]; also known as Christmas disease.<ref>PMID:8295821</ref> <ref>PMID:2592373</ref> <ref>PMID:2743975</ref> <ref>PMID:6603618</ref> <ref>PMID:3009023</ref> <ref>PMID:3790720</ref> <ref>PMID:3401602</ref> <ref>PMID:3243764</ref> <ref>PMID:2713493</ref> <ref>PMID:2714791</ref> <ref>PMID:2773937</ref> <ref>PMID:2775660</ref> <ref>PMID:2753873</ref> <ref>PMID:2738071</ref> <ref>PMID:2472424</ref> <ref>PMID:2339358</ref> <ref>PMID:2372509</ref> <ref>PMID:2162822</ref> <ref>PMID:1958666</ref> <ref>PMID:1902289</ref> <ref>PMID:1346975</ref> <ref>PMID:1615485</ref> <ref>PMID:8257988</ref> <ref>PMID:8076946</ref> <ref>PMID:8199596</ref> <ref>PMID:7981722</ref> <ref>PMID:8680410</ref> <ref>PMID:9222764</ref> <ref>PMID:9590153</ref> <ref>PMID:9452115</ref> <ref>PMID:9600455</ref> <ref>PMID:10698280</ref> <ref>PMID:10094553</ref> <ref>PMID:11122099</ref> <ref>PMID:12588353</ref> <ref>PMID:12604421</ref>   Note=Mutations in position 43 (Oxford-3, San Dimas) and 46 (Cambridge) prevents cleavage of the propeptide, mutation in position 93 (Alabama) probably fails to bind to cell membranes, mutation in position 191 (Chapel-Hill) or in position 226 (Nagoya OR Hilo) prevent cleavage of the activation peptide.  Defects in F9 are the cause of thrombophilia due to factor IX defect (THPH8) [MIM:[http://omim.org/entry/300807 300807]]. A hemostatic disorder characterized by a tendency to thrombosis.<ref>PMID:19846852</ref>  
== Function ==
[[http://www.uniprot.org/uniprot/FA9_HUMAN FA9_HUMAN]] Factor IX is a vitamin K-dependent plasma protein that participates in the intrinsic pathway of blood coagulation by converting factor X to its active form in the presence of Ca(2+) ions, phospholipids, and factor VIIIa. 
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ix/1ixa_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1ixa ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The three-dimensional structure of the first epidermal growth factor (EGF)-like module from human factor IX has been determined in solution using two-dimensional nuclear magnetic resonance (in the absence of calcium and at pH 4.5). The structure was found to resemble closely that of EGF and the homologous transforming growth factor-alpha (TGF-alpha). Residues 60-65 form an antiparallel beta-sheet with residues 68-73. In the C-terminal subdomain a type II beta-turn is found between residues 74 and 77 and a five-residue turn is found between residues 79 and 83. Glu 78 and Leu 84 pair in an antiparallel beta-sheet conformation. In the N-terminal region a loop is found between residues 50 and 55 such that the side chains of both are positioned above the face of the beta-sheet. Residues 56-60 form a turn that leads into the first strand of the beta-sheet. Whereas the global fold closely resembles that of EGF, the N-terminal residues of the module (46-49) do not form a beta-strand but are ill-defined in the structure, probably due to the local flexibility of this region. The structure is discussed with reference to recent site-directed mutagenesis data, which have identified certain conserved residues as ligands for calcium.

The three-dimensional structure of the first EGF-like module of human factor IX: comparison with EGF and TGF-alpha.,Baron M, Norman DG, Harvey TS, Handford PA, Mayhew M, Tse AG, Brownlee GG, Campbell ID Protein Sci. 1992 Jan;1(1):81-90. PMID:1304885<ref>PMID:1304885</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 1ixa" style="background-color:#fffaf0;"></div>

==See Also==
*[[Factor IX 3D structures|Factor IX 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Human]]
[[Category: Large Structures]]
[[Category: Baron, M]]
[[Category: Brownlee, G G]]
[[Category: Campbell, I D.C]]
[[Category: Hanford, P A]]
[[Category: Harvey, T S]]
[[Category: Mayhew, M]]
[[Category: Norman, D G]]
[[Category: Tse, A G.D]]
[[Category: Human factor ix]]