3d24
From Proteopedia
Crystal structure of ligand-binding domain of estrogen-related receptor alpha (ERRalpha) in complex with the peroxisome proliferators-activated receptor coactivator-1alpha box3 peptide (PGC-1alpha)
Structural highlights
FunctionERR1_HUMAN Binds to an ERR-alpha response element (ERRE) containing a single consensus half-site, 5'-TNAAGGTCA-3'. Can bind to the medium-chain acyl coenzyme A dehydrogenase (MCAD) response element NRRE-1 and may act as an important regulator of MCAD promoter. Binds to the C1 region of the lactoferrin gene promoter. Requires dimerization and the coactivator, PGC-1A, for full activity. The ERRalpha/PGC1alpha complex is a regulator of energy metabolism.[1] [2] [3] [4] [5] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedAlthough structural studies on the ligand-binding domain (LBD) have established the general mode of nuclear receptor (NR)/coactivator interaction, determinants of binding specificity are only partially understood. The LBD of estrogen receptor-alpha (ERalpha), for example, interacts only with a region of peroxisome proliferator-activated receptor coactivator (PGC)-1alpha, which contains the canonical LXXLL motif (NR box2), whereas the LBD of estrogen-related receptor-alpha (ERRalpha) also binds efficiently an untypical, LXXYL-containing region (NR box3) of PGC-1alpha. Surprisingly, in a previous structural study, the ERalpha LBD has been observed to bind NR box3 of transcriptional intermediary factor (TIF)-2 untypically via LXXYL, whereas the ERRalpha LBD binds this region of TIF-2 only poorly. Here we present a new crystal structure of the ERRalpha LBD in complex with a PGC-1alpha box3 peptide. In this structure, residues N-terminal of the PGC-1alpha LXXYL motif formed contacts with helix 4, the loop connecting helices 8 and 9, and with the C terminus of the ERRalpha LBD. Interaction studies using wild-type and mutant PGC-1alpha and ERRalpha showed that these contacts are functionally relevant and are required for efficient ERRalpha/PGC-1alpha interaction. Furthermore, a structure comparison between ERRalpha and ERalpha and mutation analyses provided evidence that the helix 8-9 loop, which differs significantly in both nuclear receptors, is a major determinant of coactivator binding specificity. Finally, our results revealed that in ERRalpha the helix 8-9 loop allosterically links the LBD homodimer interface with the coactivator cleft, thus providing a plausible explanation for distinct PGC-1alpha binding to ERRalpha monomers and homodimers. Communication between the ERRalpha homodimer interface and the PGC-1alpha binding surface via the helix 8-9 loop.,Greschik H, Althage M, Flaig R, Sato Y, Chavant V, Peluso-Iltis C, Choulier L, Cronet P, Rochel N, Schule R, Stromstedt PE, Moras D J Biol Chem. 2008 Jul 18;283(29):20220-30. Epub 2008 Apr 25. PMID:18441008[6] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. Loading citation details.. Citations No citations found See AlsoReferences
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Categories: Homo sapiens | Large Structures | Flaig R | Greschik H | Moras D | Rochel N | Sato Y