View source for 4a76


==The Lin28b Cold shock domain in complex with heptathymidine==
<StructureSection load='4a76' size='340' side='right'caption='[[4a76]], [[Resolution|resolution]] 1.92&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4a76]] is a 8 chain structure with sequence from [https://en.wikipedia.org/wiki/Xenopus_tropicalis Xenopus tropicalis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4A76 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4A76 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]] 1.92&#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=4a76 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4a76 OCA], [https://pdbe.org/4a76 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4a76 RCSB], [https://www.ebi.ac.uk/pdbsum/4a76 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4a76 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/B4F6I0_XENTR B4F6I0_XENTR] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The RNA-binding protein Lin28 regulates the processing of a developmentally important group of microRNAs, the let-7 family. Lin28 blocks the biogenesis of let-7 in embryonic stem cells and thereby prevents differentiation. It was shown that both RNA-binding domains (RBDs) of this protein, the cold-shock domain (CSD) and the zinc-knuckle domain (ZKD) are indispensable for pri- or pre-let-7 binding and blocking its maturation. Here, we systematically examined the nucleic acid-binding preferences of the Lin28 RBDs and determined the crystal structure of the Lin28 CSD in the absence and presence of nucleic acids. Both RNA-binding domains bind to single-stranded nucleic acids with the ZKD mediating specific binding to a conserved GGAG motif and the CSD showing only limited sequence specificity. However, only the isolated Lin28 CSD, but not the ZKD, can bind with a reasonable affinity to pre-let-7 and thus is able to remodel the terminal loop of pre-let-7 including the Dicer cleavage site. Further mutagenesis studies reveal that the Lin28 CSD induces a conformational change in the terminal loop of pre-let-7 and thereby facilitates a subsequent specific binding of the Lin28 ZKD to the conserved GGAG motif.

The Lin28 cold-shock domain remodels pre-let-7 microRNA.,Mayr F, Schutz A, Doge N, Heinemann U Nucleic Acids Res. 2012 May 8. PMID:22570413<ref>PMID:22570413</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4a76" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Xenopus tropicalis]]
[[Category: Doege N]]
[[Category: Heinemann U]]
[[Category: Mayr F]]
[[Category: Schuetz A]]