View source for 1mhd


==CRYSTAL STRUCTURE OF A SMAD MH1 DOMAIN BOUND TO DNA==
<StructureSection load='1mhd' size='340' side='right'caption='[[1mhd]], [[Resolution|resolution]] 2.80&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1mhd]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1MHD OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1MHD FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.8&#8491;</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1mhd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1mhd OCA], [https://pdbe.org/1mhd PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1mhd RCSB], [https://www.ebi.ac.uk/pdbsum/1mhd PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1mhd ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/SMAD3_HUMAN SMAD3_HUMAN] Defects in SMAD3 may be a cause of colorectal cancer (CRC) [MIM:[https://omim.org/entry/114500 114500].  Defects in SMAD3 are the cause of Loeys-Dietz syndrome 3 (LDS3) [MIM:[https://omim.org/entry/613795 613795]. An aortic aneurysm syndrome with widespread systemic involvement. The disorder is characterized by the triad of arterial tortuosity and aneurysms, hypertelorism, and bifid uvula or cleft palate. Patients with LDS3 also manifest early-onset osteoarthritis. They lack craniosynostosis and mental retardation. Note=SMAD3 mutations have been reported to be also associated with thoracic aortic aneurysms and dissection (TAAD) (PubMed:21778426). This phenotype is distinguised from LDS3 by having aneurysms restricted to thoracic aorta. As individuals carrying these mutations also exhibit aneurysms of other arteries, including abdominal aorta, iliac, and/or intracranial arteries (PubMed:21778426), they have been classified as LDS3 by the OMIM resource.<ref>PMID:21778426</ref> <ref>PMID:21217753</ref> 
== Function ==
[https://www.uniprot.org/uniprot/SMAD3_HUMAN SMAD3_HUMAN] Receptor-regulated SMAD (R-SMAD) that is an intracellular signal transducer and transcriptional modulator activated by TGF-beta (transforming growth factor) and activin type 1 receptor kinases. Binds the TRE element in the promoter region of many genes that are regulated by TGF-beta and, on formation of the SMAD3/SMAD4 complex, activates transcription. Also can form a SMAD3/SMAD4/JUN/FOS complex at the AP-1/SMAD site to regulate TGF-beta-mediated transcription. Has an inhibitory effect on wound healing probably by modulating both growth and migration of primary keratinocytes and by altering the TGF-mediated chemotaxis of monocytes. This effect on wound healing appears to be hormone-sensitive. Regulator of chondrogenesis and osteogenesis and inhibits early healing of bone fractures (By similarity). Positively regulates PDPK1 kinase activity by stimulating its dissociation from the 14-3-3 protein YWHAQ which acts as a negative regulator.<ref>PMID:9732876</ref> <ref>PMID:9892009</ref> <ref>PMID:10995748</ref> <ref>PMID:15241418</ref> <ref>PMID:15588252</ref> <ref>PMID:16156666</ref> <ref>PMID:16751101</ref> <ref>PMID:17327236</ref> <ref>PMID:16862174</ref> <ref>PMID:19289081</ref> <ref>PMID:19218245</ref> 
== 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/mh/1mhd_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.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=1mhd ConSurf].
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== Publication Abstract from PubMed ==
The Smad family of proteins, which are frequently targeted by tumorigenic mutations in cancer, mediate TGF-beta signaling from cell membrane to nucleus. The crystal structure of a Smad3 MH1 domain bound to an optimal DNA sequence determined at 2.8 A resolution reveals a novel DNA-binding motif. In the crystals, base-specific DNA recognition is provided exclusively by a conserved 11-residue beta hairpin that is embedded in the major groove of DNA. A surface loop region, to which tumorigenic mutations map, has been identified as a functional surface important for Smad activity. This structure establishes a framework for understanding how Smad proteins may act in concert with other transcription factors in the regulation of TGF-beta-responsive genes.

Crystal structure of a Smad MH1 domain bound to DNA: insights on DNA binding in TGF-beta signaling.,Shi Y, Wang YF, Jayaraman L, Yang H, Massague J, Pavletich NP Cell. 1998 Sep 4;94(5):585-94. PMID:9741623<ref>PMID:9741623</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Shi Y]]