1m1u
From Proteopedia
Line 1: | Line 1: | ||
[[Image:1m1u.jpg|left|200px]] | [[Image:1m1u.jpg|left|200px]] | ||
- | + | <!-- | |
- | + | The line below this paragraph, containing "STRUCTURE_1m1u", creates the "Structure Box" on the page. | |
- | + | You may change the PDB parameter (which sets the PDB file loaded into the applet) | |
- | + | or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |
- | + | or leave the SCENE parameter empty for the default display. | |
- | + | --> | |
- | + | {{STRUCTURE_1m1u| PDB=1m1u | SCENE= }} | |
- | + | ||
- | + | ||
- | }} | + | |
'''AN ISOLEUCINE-BASED ALLOSTERIC SWITCH CONTROLS AFFINITY AND SHAPE SHIFTING IN INTEGRIN CD11B A-DOMAIN''' | '''AN ISOLEUCINE-BASED ALLOSTERIC SWITCH CONTROLS AFFINITY AND SHAPE SHIFTING IN INTEGRIN CD11B A-DOMAIN''' | ||
Line 30: | Line 27: | ||
[[Category: Stehle, T.]] | [[Category: Stehle, T.]] | ||
[[Category: Xiong, J P.]] | [[Category: Xiong, J P.]] | ||
- | [[Category: | + | [[Category: A-domain]] |
- | [[Category: | + | [[Category: Cd11b]] |
- | [[Category: | + | [[Category: Cell adhesion protein]] |
- | [[Category: | + | [[Category: Glycoprotein]] |
- | [[Category: | + | [[Category: Integrin]] |
- | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 00:32:00 2008'' | |
- | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + |
Revision as of 21:32, 2 May 2008
AN ISOLEUCINE-BASED ALLOSTERIC SWITCH CONTROLS AFFINITY AND SHAPE SHIFTING IN INTEGRIN CD11B A-DOMAIN
Overview
In response to cell activation signals, integrins switch from a low to a high affinity state. Physiologic ligands bind to integrins through a von Willebrand Factor A-type domain. Crystallographic studies revealed two conformations of this domain, "closed" and "open." The latter crystallizes in complex with a pseudoligand or ligand, suggesting that it represents the high affinity state; data linking structure and activity are lacking however. In this communication, we expressed stable low and high affinity forms of integrin CD11b A-domain and determined their binding isotherms and crystal structures. The low affinity form, generated by deleting an N-terminal extension extrinsic to the domain, did not bind to physiologic ligands, and crystallized in the closed conformation. The high affinity form was generated by either deleting or substituting an invariable C-terminal Ile(316), wedged into a hydrophobic socket in the closed form, but displaced from it in the open structure. Both mutants crystallized in the open conformation, and the Ile(316) --> Gly-modified integrin displayed high affinity. Structural differences between the low and high affinity forms were detected in solution. These data establish the structure-function correlates for the CD11b A-domain, and define a ligand-independent isoleucine-based allosteric switch intrinsic to this domain that controls its conformation and affinity.
About this Structure
1M1U is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
An isoleucine-based allosteric switch controls affinity and shape shifting in integrin CD11b A-domain., Xiong JP, Li R, Essafi M, Stehle T, Arnaout MA, J Biol Chem. 2000 Dec 8;275(49):38762-7. PMID:11034990 Page seeded by OCA on Sat May 3 00:32:00 2008
Categories: Homo sapiens | Single protein | Arnaout, M A. | Essafi, M. | Li, R. | Stehle, T. | Xiong, J P. | A-domain | Cd11b | Cell adhesion protein | Glycoprotein | Integrin