biostudies-literatureSaito ANTakeda Science FoundationJapan Society for the Promotion of Science1720-1728https://www.ebi.ac.uk/biostudies/studies/S-EPMC9680855biostudies-literatureUnknown63(11)The circadian clock, an internal time-keeping system with a period of about 24 h, coordinates many physiological processes with the day-night cycle. We previously demonstrated that BML-259 [N-(5-isopropyl-2-thiazolyl) phenylacetamide], a small molecule with mammal CYCLIN DEPENDENT KINASE 5 (CDK5)/CDK2 inhibition activity, lengthens Arabidopsis thaliana (Arabidopsis) circadian clock periods. BML-259 inhibits Arabidopsis CDKC kinase, which phosphorylates RNA polymerase II in the general transcriptional machinery. To accelerate our understanding of the inhibitory mechanism of BML-259 on CDKC, we performed structure-function studies of BML-259 using circadian period-lengthening activity as an estimation of CDKC inhibitor activity in vivo. The presence of a thiazole ring is essential for periodPlant & cell physiologyStructure-Function Study of a Novel Inhibitor of Cyclin-Dependent Kinase C in Arabidopsis.PMC968085518H0442820H0541120K2127221H05656Matsuo HFujimoto KJMaeda AENakamichi NNishina MYanai TOta ENotaguchi MSaito ANTakahara TTKinoshita TYamaguchi JOno AShiratake KfalseStructure-Function Study of a Novel Inhibitor of Cyclin-Dependent Kinase C in Arabidopsis.The circadian clock, an internal time-keeping system with a period of about 24 h, coordinates many physiological processes with the day-night cycle. We previously demonstrated that BML-259 [N-(5-isopropyl-2-thiazolyl) phenylacetamide], a small molecule with mammal CYCLIN DEPENDENT KINASE 5 (CDK5)/CDK2 inhibition activity, lengthens Arabidopsis thaliana (Arabidopsis) circadian clock periods. BML-259 inhibits Arabidopsis CDKC kinase, which phosphorylates RNA polymerase II in the general transcriptional machinery. To accelerate our understanding of the inhibitory mechanism of BML-259 on CDKC, we performed structure-function studies of BML-259 using circadian period-lengthening activity as an estimation of CDKC inhibitor activity in vivo. The presence of a thiazole ring is essential for period2022-01-01T00:00:00Z2022 Nov2026-04-08T11:06:32.928Z2025-04-19T06:03:29.961ZS-EPMC96808553604369210.1093/pcp/pcac127