|4ed5, resolution 2.00Å ()|
|Gene:||ELAVL1, HUR (Homo sapiens)|
Crystal structure of the two N-terminal RRM domains of HuR complexed with RNA
Human RNA-binding protein (HuR), a ubiquitously expressed member of the Hu protein family, plays an important role in mRNA degradation and has been implicated as a key post-transcriptional regulator. HuR contains three RNA-recognition motif (RRM) domains. The two N-terminal tandem RRM domains can selectively bind AU-rich elements (AREs), while the third RRM domain (RRM3) contributes to interactions with the poly-A tail of target mRNA and other ligands. Here, the X-ray structure of two methylated tandem RRM domains (RRM1/2) of HuR in their RNA-free form was solved at 2.9 A resolution. The crystal structure of RRM1/2 complexed with target mRNA was also solved at 2.0 A resolution; comparisons of the two structures show that HuR RRM1/2 undergoes conformational changes upon RNA binding. Fluorescence polarization assays (FPA) were used to study the protein-RNA interactions. Both the structure and the FPA analysis indicated that RRM1 is the primary ARE-binding domain in HuR and that the conformational changes induce subsequent contacts of the RNA substrate with the inter-domain linker and RRM2 which greatly improve the RNA-binding affinity of HuR.
The structure of the ARE-binding domains of Hu antigen R (HuR) undergoes conformational changes during RNA binding., Wang H, Zeng F, Liu Q, Liu H, Liu Z, Niu L, Teng M, Li X, Acta Crystallogr D Biol Crystallogr. 2013 Mar;69(Pt 3):373-80. doi:, 10.1107/S0907444912047828. Epub 2013 Feb 16. PMID:23519412
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
[ELAV1_HUMAN] Involved in 3'-UTR ARE-mediated MYC stabilization. Binds avidly to the AU-rich element in FOS and IL3/interleukin-3 mRNAs. In the case of the FOS AU-rich element, HUR binds to a core element of 27 nucleotides that contain AUUUA, AUUUUA and AUUUUUA motifs. Binds preferentially to the 5'-UUUU[AG]UUU-3' motif in vitro.