Arabidopsis KRPs have distinct inhibitory activity toward cyclin D2-associated kinases, including plant-specific B-type cyclin-dependent kinase.
Arabidopsis contains seven Kip-related protein (KRP) genes encoding CDK (cyclin-dependent kinase) inhibitors (CKIs), which shares a restricted similarity with mammalian p27Kip1. Here, we analyze the characteristics of the KRPs. Although KRP1-KRP7 interact with active cyclin D2 (CYCD2)/CDKA and CYCD2/CDKB complexes to a similar extent, they inhibit kinase activity to a different extent. Our results suggest that inhibitory activity is related to the binding ability between KRP proteins and cyclin/CDK complexes, but secondary and tertiary structure may be also involved. These data provide the first evidence that KRPs inhibit kinase activity associated with plant-specific CDKB.
Nakai
Tomohiro
T
Graduate School of Biological Sciences, Nara Institute of Science and Technology (NAIST), Takayama 8916-5, Ikoma, Nara 630-0101, Japan.
Kato
Ko
K
Shinmyo
Atsuhiko
A
Sekine
Masami
M
D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D050756:Cyclin-Dependent Kinase Inhibitor Proteins / Q000378:metabolism*; D050760:Cyclin-Dependent Kinase Inhibitor p27 / Q000378:metabolism; D018844:Cyclin-Dependent Kinases / Q000378:metabolism*; D016213:Cyclins / Q000378:metabolism*; D046912:Multiprotein Complexes / Q000378:metabolism*; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid
D029681:Arabidopsis Proteins; C486198:CycD2 protein, Arabidopsis; D050756:Cyclin-Dependent Kinase Inhibitor Proteins; D016213:Cyclins; D046912:Multiprotein Complexes; D050760:Cyclin-Dependent Kinase Inhibitor p27; C434472:CDKA1 protein, Arabidopsis; D018844:Cyclin-Dependent Kinases