| dc.creator |
Monleón, Daniel |
|
| dc.creator |
Esteve, Vicent |
|
| dc.creator |
Kovacs, Helena |
|
| dc.creator |
Calvete, Juan J. |
|
| dc.creator |
Celda, Bernardo |
|
| dc.date |
2008-04-15T07:45:49Z |
|
| dc.date |
2008-04-15T07:45:49Z |
|
| dc.date |
2005-03-22 |
|
| dc.date.accessioned |
2017-01-31T01:02:18Z |
|
| dc.date.available |
2017-01-31T01:02:18Z |
|
| dc.identifier |
Biochem J. 2005 April 1; 387(Pt 1): 57–66 |
|
| dc.identifier |
1470-8728 |
|
| dc.identifier |
http://hdl.handle.net/10261/3577 |
|
| dc.identifier |
10.1042/BJ20041343 |
|
| dc.identifier.uri |
http://dspace.mediu.edu.my:8181/xmlui/handle/10261/3577 |
|
| dc.description |
Copyright © by Portland Press. The final version of record is available at http://www.biochemj.org/bj/default.htm |
|
| dc.description |
Echistatin is a potent antagonist of the integrins αvβ3, α5β1 and αIIbβ3. Its full inhibitory activity depends on an RGD (Arg-Gly-Asp) motif expressed at the tip of the integrin-binding loop and on its C-terminal tail. Previous NMR structures of echistatin showed a poorly defined integrin-recognition sequence and an incomplete C-terminal tail, which left the molecular basis of the functional synergy between the RGD loop and the C-terminal region unresolved. We report a high-resolution structure of echistatin and an analysis of its internal motions by off-resonance ROESY (rotating-frame Overhauser enhancement spectroscopy). The full-length C-terminal polypeptide is visible as a β-hairpin running parallel to the RGD loop and exposing at the tip residues Pro43, His44 and Lys45. The side chains of the amino acids of the RGD motif have well-defined conformations. The integrin-binding loop displays an overall movement with maximal amplitude of 30°. Internal angular motions in the 100–300 ps timescale indicate increased flexibility for the backbone atoms at the base of the integrin-recognition loop. In addition, backbone atoms of the amino acids Ala23 (flanking the R24GD26 tripeptide) and Asp26 of the integrin-binding motif showed increased angular mobility, suggesting the existence of major and minor hinge effects at the base and the tip, respectively, of the RGD loop. A strong network of NOEs (nuclear Overhauser effects) between residues of the RGD loop and the C-terminal tail indicate concerted motions between these two functional regions. A full-length echistatin–αvβ3 docking model suggests that echistatin's C-terminal amino acids may contact αv-subunit residues and provides new insights to delineate structure–function correlations. |
|
| dc.description |
This study has been partly financed by grants BCM2001-3337 from the Ministerio de Ciencia y Tecnología, and BFU2004-01432/BMC from the Ministerio de Educación y Ciencia, Madrid, Spain (to J.J.C.). We also thank Bruker España S.A. for financial support. Thanks are also due to the SCSIE of the University of Valencia for providing access to the NMR facility and to high-performance computing facilities. |
|
| dc.description |
Peer reviewed |
|
| dc.format |
796251 bytes |
|
| dc.format |
application/pdf |
|
| dc.language |
eng |
|
| dc.publisher |
Biochemical Society |
|
| dc.rights |
closedAccess |
|
| dc.subject |
RGD disintegrin |
|
| dc.subject |
Echistatin, integrin |
|
| dc.subject |
NMR protein dynamics determination |
|
| dc.subject |
Off-resonance rotating-frame Overhauser enhancement spectroscopy (off-resonance ROESY) |
|
| dc.title |
Conformation and concerted dynamics of the integrin-binding site and the C-terminal region of echistatin revealed by homonuclear NMR |
|
| dc.type |
Artículo |
|