View source for 3agv


==Crystal structure of a human IgG-aptamer complex==
<StructureSection load='3agv' size='340' side='right'caption='[[3agv]], [[Resolution|resolution]] 2.15&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3agv]] 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=3AGV OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3AGV 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]] 2.15&#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=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=CFZ:2-DEOXY-2-FLUOROCYTIDINE+5-(DIHYDROGEN+PHOSPHATE)'>CFZ</scene>, <scene name='pdbligand=FUL:BETA-L-FUCOSE'>FUL</scene>, <scene name='pdbligand=GAL:BETA-D-GALACTOSE'>GAL</scene>, <scene name='pdbligand=GLA:ALPHA+D-GALACTOSE'>GLA</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>, <scene name='pdbligand=UFT:2-DEOXY-2-FLUOROURIDINE+5-(DIHYDROGEN+PHOSPHATE)'>UFT</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=3agv FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3agv OCA], [https://pdbe.org/3agv PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3agv RCSB], [https://www.ebi.ac.uk/pdbsum/3agv PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3agv ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/IGHG1_HUMAN IGHG1_HUMAN] Defects in IGHG1 are a cause of multiple myeloma (MM) [MIM:[https://omim.org/entry/254500 254500]. MM is a malignant tumor of plasma cells usually arising in the bone marrow and characterized by diffuse involvement of the skeletal system, hyperglobulinemia, Bence-Jones proteinuria and anemia. Complications of multiple myeloma are bone pain, hypercalcemia, renal failure and spinal cord compression. The aberrant antibodies that are produced lead to impaired humoral immunity and patients have a high prevalence of infection. Amyloidosis may develop in some patients. Multiple myeloma is part of a spectrum of diseases ranging from monoclonal gammopathy of unknown significance (MGUS) to plasma cell leukemia. Note=A chromosomal aberration involving IGHG1 is found in multiple myeloma. Translocation t(11;14)(q13;q32) with the IgH locus. Translocation t(11;14)(q13;q32) with CCND1; translocation t(4;14)(p16.3;q32.3) with FGFR3; translocation t(6;14)(p25;q32) with IRF4.
== Function ==
[https://www.uniprot.org/uniprot/IGHG1_HUMAN IGHG1_HUMAN] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Aptamers are short single-stranded nucleic acids with high affinity to target molecules and are applicable to therapeutics and diagnostics. Regardless of an increasing number of reported aptamers, the structural basis of the interaction of RNA aptamer with proteins is poorly understood. Here, we determined the 2.15 A crystal structure of the Fc fragment of human IgG1 (hFc1) complexed with an anti-Fc RNA aptamer. The aptamer adopts a characteristic structure fit to hFc1 that is stabilized by a calcium ion, and the binding activity of the aptamer can be controlled many times by calcium chelation and addition. Importantly, the aptamer-hFc1 interaction involves mainly van der Waals contacts and hydrogen bonds rather than electrostatic forces, in contrast to other known aptamer-protein complexes. Moreover, the aptamer-hFc1 interaction involves human IgG-specific amino acids, rendering the aptamer specific to human IgGs, and not crossreactive to other species IgGs. Hence, the aptamer is a potent alternative for protein A affinity purification of Fc-fusion proteins and therapeutic antibodies. These results demonstrate, from a structural viewpoint, that conformational plasticity and selectivity of an RNA aptamer is achieved by multiple interactions other than electrostatic forces, which is applicable to many protein targets of low or no affinity to nucleic acids.

Conformational plasticity of RNA for target recognition as revealed by the 2.15 A crystal structure of a human IgG-aptamer complex.,Nomura Y, Sugiyama S, Sakamoto T, Miyakawa S, Adachi H, Takano K, Murakami S, Inoue T, Mori Y, Nakamura Y, Matsumura H Nucleic Acids Res. 2010 Jul 30. PMID:20675355<ref>PMID:20675355</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 3agv" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Adachi H]]
[[Category: Inoue T]]
[[Category: Matsumura H]]
[[Category: Miyakawa S]]
[[Category: Mori Y]]
[[Category: Murakami S]]
[[Category: Nakamura Y]]
[[Category: Nomura Y]]
[[Category: Sakamoto T]]
[[Category: Sugiyama S]]
[[Category: Takano K]]