title: Screening of protein kinase inhibitors and knockdown experiments identified four kinases that affect mitochondrial ATP synthesis activity.
abstract: Mitochondrial ATP synthase, a major ATP supplier in respiring cells, should be regulated in amount and in activity to respond to the varying demands of cells for ATP. We screened 80 protein kinase inhibitors and found that HeLa cells treated with four inhibitors exhibited reduced mitochondrial ATP synthesis activity. Consistently, knockdown of their target kinases (PKA, PKCδ, CaMKII and smMLCK) resulted in a decrease in mitochondrial ATP synthesis activity. Among them, mitochondria of smMLCK-knockdown cells contained only a small amount of ATP synthase, while the α- and β-subunits of ATP synthase were produced normally, suggesting that smMLCK affects assembly (or decay) of ATP synthase.
authors.affiliation: International Cooperative Research Project (ICORP), ATP Synthesis Regulation Project, Japan Science and Technology Agency, Aomi 2-3-6, Tokyo 135-0064, Japan; Department of Molecular Bioscience, Kyoto Sangyo University, Kamigamo-Motoyama, Kyoto 603-8555, Japan.
authors.forename: Kanako
authors.initials: K
authors.lastname: Sugawara
authors.forename: Makoto
authors.initials: M
authors.lastname: Fujikawa
authors.forename: Masasuke
authors.initials: M
authors.lastname: Yoshida
mesh_terms: D000255:Adenosine Triphosphate / Q000096:biosynthesis*; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2 / Q000037:antagonists & inhibitors; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors; D006367:HeLa Cells; D006801:Humans; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D025261:Mitochondrial Proton-Translocating ATPases / Q000235:genetics / Q000378:metabolism; D009219:Myosin-Light-Chain Kinase / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D051745:Protein Kinase C-delta / Q000037:antagonists & inhibitors; D047428:Protein Kinase Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering
chemical_list: D047428:Protein Kinase Inhibitors; D021122:Protein Subunits; D034741:RNA, Small Interfering; D000255:Adenosine Triphosphate; D017868:Cyclic AMP-Dependent Protein Kinases; D051745:Protein Kinase C-delta; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D009219:Myosin-Light-Chain Kinase; D025261:Mitochondrial Proton-Translocating ATPases
keywords: ATP synthase; ATP synthesis; CaMKII; F(o)F(1); MASC assay; MLCK; Myosin light chain kinase; PKA; PKC; Protein kinase; VDAC; calcium/calmodulin-dependent protein kinase 2; miRNA; microRNA used for knockdown; mitochondrial activity of SLO-permeabilized cells assay; protein kinase A; protein kinase C; smMLCK; smooth muscle type myosin light chain kinase; voltage-dependent anion channel of mitochondria