Download MendeleyParallel coiled-coil association of the RhoA-binding domain in Rho-kinase
Shimizu, T., Ihara, K., Maesaki, R., Amano, M., Kaibuchi, K., Hakoshima, T.(2003) J Biol Chem 278: 46046-46051
- PubMed: 12954645
- DOI: https://doi.org/10.1074/jbc.M306458200
- Primary Citation of Related Structures:
1UIX - PubMed Abstract:
Rho-kinase is a serine/threonine protein kinase that regulates cytoskeletal events in cells. The enzyme activity of Rho-kinase is auto-inhibited in the free state but is activated through direct binding to the small GTPase Rho in the GTP-bound form. The crystal structure of the Rho-binding domain (RhoBD) of Rho-kinase has been determined at 1.8-A resolution by the multi-wavelength anomalous dispersion technique. The structure shows that RhoBD dimerizes to form a parallel coiled-coil with long consecutive alpha-helices extended to approximately 97 A and suggests that free Rho-kinase can also form a dimer through parallel self-association. At the middle region of the coiled-coil, the polypeptide chains are flexible and display loose "knobs-into-holes" packing of the side chains from both chains. RhoBD residues that have been shown to be critical for Rho-binding are spread in the positively charged C-terminal region. The parallel coiled-coil structure of our Rho-kinase RhoBD in the free form is different from the anti-parallel coiled-coil structure of RhoBD of protein kinase N when complexed with RhoA. Implications derived from these structural studies in relation to the mechanism of Rho-kinase activation will be addressed with previously reported experimental data.
Organizational Affiliation:
Structural Biology Laboratory, Nara Institute of Science and Technology, and CREST, Japan Science and Technology Corporation, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
