 |
PDBsum entry 3cs8
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Nuclear protein
|
PDB id
|
|
|
|
3cs8
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
Structural and biochemical basis for the binding selectivity of peroxisome proliferator-Activated receptor gamma to pgc-1alpha.
|
|
|
Authors
|
|
Y.Li,
A.Kovach,
K.Suino-Powell,
D.Martynowski,
H.E.Xu.
|
|
|
Ref.
|
|
J Biol Chem, 2008,
283,
19132-19139.
[DOI no: ]
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
The functional interaction between the peroxisome proliferator-activated
receptor gamma (PPARgamma) and its coactivator PGC-1alpha is crucial for the
normal physiology of PPARgamma and its pharmacological response to antidiabetic
treatment with rosiglitazone. Here we report the crystal structure of the
PPARgamma ligand-binding domain bound to rosiglitazone and to a large PGC-1alpha
fragment that contains two LXXLL-related motifs. The structure reveals critical
contacts mediated through the first LXXLL motif of PGC-1alpha and the PPARgamma
coactivator binding site. Through a combination of biochemical and structural
studies, we demonstrate that the first LXXLL motif is the most potent among all
nuclear receptor coactivator motifs tested, and only this motif of the two
LXXLL-related motifs in PGC-1alpha is capable of binding to PPARgamma. Our
studies reveal that the strong interaction of PGC-1alpha and PPARgamma is
mediated through both hydrophobic and specific polar interactions. Mutations
within the context of the full-length PGC-1alpha indicate that the first
PGC-1alpha motif is necessary and sufficient for PGC-1alpha to coactivate
PPARgamma in the presence or absence of rosiglitazone. These results provide a
molecular basis for specific recruitment and functional interplay between
PPARgamma and PGC-1alpha in glucose homeostasis and adipocyte differentiation.
|
|
|
|
|
|
|
|
Figure 3.
FIGURE 3. Purification and crystallization of the PPAR  LBD
complexed with a PGC-1  fragment. A, a
schematic representation showing the PGC-1 protein and its two
receptor-interacting motifs (ID1 and ID2). The PGC-1 fragment
(101-220) that includes both ID1 and ID2 motifs was used in
cocrystallization with PPAR . B, purification of
the PPAR LBD and PGC-1 complex.
The proteins of PPAR and PGC-1 were
purified separately and complexed using excess PGC-1 in the
presence of rosiglitazone. The PPAR ·PGC-1 complex
and PGC-1 alone were separated by
gel filtration. The complex was eluted in the first peak and
collected and concentrated to 10 mg/ml for the crystallization
trial. C, the protein complex samples shown on an SDS gel. The
molecular mass markers are shown in the KD lane (kilodaltons).
Lanes 1-9 are fractions from the gel filtration column
corresponding to the two peaks in B, from left to right. D,
crystals of the PPAR ·rosiglitazone·PGC-1
complex.
|
|
Figure 6.
FIGURE 6. Molecular determinants of the PGC-1 /PPAR
interactions. A and B,
the docking mode of PGC-1 ID1 (yellow) on the
surface of PPAR (coactivator binding
site) is shown. The hydrophobic interaction is shown in A, and
the specific intermolecular interaction is shown in B. C and D,
the binding interface of PGC-1 /PPAR shows
the specific intermolecular and intramolecular interactions. The
PGC-1 is shown in green, the
PPAR is in red, and the
hydrogen bonds are shown as arrows.
|
|
|
|
|
|
The above figures are
reprinted
by permission from the ASBMB:
J Biol Chem
(2008,
283,
19132-19139)
copyright 2008.
|
|
|
|
|
|
|
