title: Peptide substrates for Rho-associated kinase 2 (Rho-kinase 2/ROCK2).
abstract: Peptide substrates sensitive for a certain protein kinase could be important for new-drug development and to understand the mechanism of diseases. Rho-associated kinase (Rho-kinase/ROCK) is a serine/threonine kinase, and plays an important part in cardiovascular disease, migration and invasion of tumor cells, and in neurological disorders. The purpose of this study was to find substrates with high affinity and sensitivity for ROCK2. We synthesized 136 peptide substrates from protein substrates for ROCK2 with different lengths and charged peptides. Incorporation of (32)P [counts per minute (CPM)] for each peptide substrate was determined by the radiolabel assay using [γ-(32)P]ATP. When the top five peptide substrates showing high CPMs (R4, R22, R133, R134, and R135) were phosphorylated by other enzymes (PKA, PKCα, and ERK1), R22, R133, and R135 displayed the highest CPM level for ROCK2 compared with other enzymes, whereas R4 and R134 showed similar CPM levels for ROCK2 and PKCα. We hypothesize that R22, R133, and R135 can be useful peptide substrates for ROCK2.
authors.affiliation: Department of Biomedical Engineering, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan. jrjhkang@ri.ncvc.go.jp
authors.forename: Jeong-Hun
authors.initials: JH
authors.lastname: Kang
authors.forename: Daisuke
authors.initials: D
authors.lastname: Asai
authors.forename: Akira
authors.initials: A
authors.lastname: Tsuchiya
authors.forename: Takeshi
authors.initials: T
authors.lastname: Mori
authors.forename: Takuro
authors.initials: T
authors.lastname: Niidome
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Katayama
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D010766:Phosphorylation; D011851:Radioactivity; D013379:Substrate Specificity; D054460:rho-Associated Kinases / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D010455:Peptides; D054460:rho-Associated Kinases