View source for 2ifg


==Structure of the extracellular segment of human TRKA in complex with nerve growth factor==
<StructureSection load='2ifg' size='340' side='right'caption='[[2ifg]], [[Resolution|resolution]] 3.40&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2ifg]] 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=2IFG OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2IFG 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]] 3.4&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BMA:BETA-D-MANNOSE'>BMA</scene>, <scene name='pdbligand=MAN:ALPHA-D-MANNOSE'>MAN</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=NDG:2-(ACETYLAMINO)-2-DEOXY-A-D-GLUCOPYRANOSE'>NDG</scene></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=2ifg FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ifg OCA], [https://pdbe.org/2ifg PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2ifg RCSB], [https://www.ebi.ac.uk/pdbsum/2ifg PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2ifg ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/NTRK1_HUMAN NTRK1_HUMAN] Defects in NTRK1 are a cause of congenital insensitivity to pain with anhidrosis (CIPA) [MIM:[https://omim.org/entry/256800 256800]. CIPA is characterized by a congenital insensitivity to pain, anhidrosis (absence of sweating), absence of reaction to noxious stimuli, self-mutilating behavior, and mental retardation. This rare autosomal recessive disorder is also known as congenital sensory neuropathy with anhidrosis or hereditary sensory and autonomic neuropathy type IV or familial dysautonomia type II.<ref>PMID:8696348</ref> <ref>PMID:10090906</ref> <ref>PMID:10330344</ref> <ref>PMID:10233776</ref> <ref>PMID:10861667</ref> <ref>PMID:10982191</ref> <ref>PMID:10567924</ref> <ref>PMID:11310631</ref> <ref>PMID:11159935</ref> <ref>PMID:22302274</ref>   Defects in NTRK1 are a cause of thyroid papillary carcinoma (TPC) [MIM:[https://omim.org/entry/188550 188550]. TPC is a common tumor of the thyroid that typically arises as an irregular, solid or cystic mass from otherwise normal thyroid tissue. Papillary carcinomas are malignant neoplasm characterized by the formation of numerous, irregular, finger-like projections of fibrous stroma that is covered with a surface layer of neoplastic epithelial cells. Note=Chromosomal aberrations involving NTRK1 are found in thyroid papillary carcinomas. Translocation t(1;3)(q21;q11) with TFG generates the TRKT3 (TRK-T3) transcript by fusing TFG to the 3'-end of NTRK1; a rearrangement with TPM3 generates the TRK transcript by fusing TPM3 to the 3'-end of NTRK1; an intrachromosomal rearrangement that links the protein kinase domain of NTRK1 to the 5'-end of the TPR gene forms the fusion protein TRK-T1. TRK-T1 is a 55 kDa protein reacting with antibodies against the C-terminus of the NTRK1 protein.
== Function ==
[https://www.uniprot.org/uniprot/NTRK1_HUMAN NTRK1_HUMAN] Receptor tyrosine kinase involved in the development and the maturation of the central and peripheral nervous systems through regulation of proliferation, differentiation and survival of sympathetic and nervous neurons. High affinity receptor for NGF which is its primary ligand, it can also bind and be activated by NTF3/neurotrophin-3. However, NTF3 only supports axonal extension through NTRK1 but has no effect on neuron survival. Upon dimeric NGF ligand-binding, undergoes homodimerization, autophosphorylation and activation. Recruits, phosphorylates and/or activates several downstream effectors including SHC1, FRS2, SH2B1, SH2B2 and PLCG1 that regulate distinct overlapping signaling cascades driving cell survival and differentiation. Through SHC1 and FRS2 activates a GRB2-Ras-MAPK cascade that regulates cell differentiation and survival. Through PLCG1 controls NF-Kappa-B activation and the transcription of genes involved in cell survival. Through SHC1 and SH2B1 controls a Ras-PI3 kinase-AKT1 signaling cascade that is also regulating survival. In absence of ligand and activation, may promote cell death, making the survival of neurons dependent on trophic factors.<ref>PMID:1850821</ref> <ref>PMID:1849459</ref> <ref>PMID:8325889</ref> <ref>PMID:8155326</ref> <ref>PMID:11244088</ref> <ref>PMID:15488758</ref>   Isoform TrkA-III is resistant to NGF, constitutively activates AKT1 and NF-kappa-B and is unable to activate the Ras-MAPK signaling cascade. Antagonizes the anti-proliferative NGF-NTRK1 signaling that promotes neuronal precursors differentiation. Isoform TrkA-III promotes angiogenesis and has oncogenic activity when overexpressed.<ref>PMID:1850821</ref> <ref>PMID:1849459</ref> <ref>PMID:8325889</ref> <ref>PMID:8155326</ref> <ref>PMID:11244088</ref> <ref>PMID:15488758</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/if/2ifg_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=2ifg ConSurf].
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== Publication Abstract from PubMed ==
Nerve growth factor engages two structurally distinct transmembrane receptors, TrkA and p75, which have been proposed to create a "high-affinity" NGF binding site through formation of a ternary TrkA/NGF/p75 complex. To define a structural basis for the high-affinity site, we have determined the three-dimensional structure of a complete extracellular domain of TrkA complexed with NGF. The complex reveals a crab-shaped homodimeric TrkA structure, but a mechanism for p75 coordination is not obvious. We investigated the heterodimerization of membrane-bound TrkA and p75, on intact mammalian cells, using a beta-gal protein-protein interaction system. We find that NGF dimerizes TrkA and that p75 exists on the cell surface as a preformed oligomer that is not dissociated by NGF. We find no evidence for a direct TrkA/p75 interaction. We propose that TrkA and p75 likely communicate through convergence of downstream signaling pathways and/or shared adaptor molecules, rather than through direct extracellular interactions.

Structural and mechanistic insights into nerve growth factor interactions with the TrkA and p75 receptors.,Wehrman T, He X, Raab B, Dukipatti A, Blau H, Garcia KC Neuron. 2007 Jan 4;53(1):25-38. PMID:17196528<ref>PMID:17196528</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 2ifg" style="background-color:#fffaf0;"></div>

==See Also==
*[[High affinity nerve growth factor receptor|High affinity nerve growth factor receptor]]
*[[Nerve growth factor|Nerve growth factor]]
*[[Tyrosine kinase receptor|Tyrosine kinase receptor]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Garcia KC]]
[[Category: He X]]