title: Cardiac protein kinases: the cardiomyocyte kinome and differential kinase expression in human failing hearts.
abstract: OBJECTIVE
  Protein kinases are potential therapeutic targets for heart failure, but most studies of cardiac protein kinases derive from other systems, an approach that fails to account for specific kinases expressed in the heart and the contractile cardiomyocytes. We aimed to define the cardiomyocyte kinome (i.e. the protein kinases expressed in cardiomyocytes) and identify kinases with altered expression in human failing hearts.
  
  
  RESULTS
  Expression profiling (Affymetrix microarrays) detected >400 protein kinase mRNAs in rat neonatal ventricular myocytes (NVMs) and/or adult ventricular myocytes (AVMs), 32 and 93 of which were significantly up-regulated or down-regulated (greater than two-fold), respectively, in AVMs. Data for AGC family members were validated by qPCR. Proteomics analysis identified >180 cardiomyocyte protein kinases, with high relative expression of mitogen-activated protein kinase cascades and other known cardiomyocyte kinases (e.g. CAMKs, cAMP-dependent protein kinase). Other kinases are poorly investigated (e.g. Slk, Stk24, Oxsr1). Expression of Akt1/2/3, BRaf, ERK1/2, Map2k1, Map3k8, Map4k4, MST1/3, p38-MAPK, PKCδ, Pkn2, Ripk1/2, Tnni3k, and Zak was confirmed by immunoblotting. Relative to total protein, Map3k8 and Tnni3k were up-regulated in AVMs vs. NVMs. Microarray data for human hearts demonstrated variation in kinome expression that may influence responses to kinase inhibitor therapies. Furthermore, some kinases were up-regulated (e.g. NRK, JAK2, STK38L) or down-regulated (e.g. MAP2K1, IRAK1, STK40) in human failing hearts.
  
  
  CONCLUSIONS
  This characterization of the spectrum of kinases expressed in cardiomyocytes and the heart (cardiomyocyte and cardiac kinomes) identified novel kinases, some of which are differentially expressed in failing human hearts and could serve as potential therapeutic targets.
authors.affiliation: School of Biological Sciences, University of Reading, Whiteknights Campus, Reading, Berkshire RG6 6AS, UK.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Fuller
authors.affiliation: School of Biological Sciences, University of Reading, Whiteknights Campus, Reading, Berkshire RG6 6AS, UK.
authors.forename: Sally A
authors.initials: SA
authors.lastname: Osborne
authors.affiliation: School of Biological Sciences, University of Reading, Whiteknights Campus, Reading, Berkshire RG6 6AS, UK.
authors.forename: Sam J
authors.initials: SJ
authors.lastname: Leonard
authors.affiliation: School of Biological Sciences, University of Reading, Whiteknights Campus, Reading, Berkshire RG6 6AS, UK.
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Hardyman
authors.affiliation: Institut de Cardiologie de Montréal Centre de Recherche, Montréal, QC, Canada H1T 1C8 Département de Biochimie, Université de Montréal, Montréal, QC, Canada H3T 1J4.
authors.forename: George
authors.initials: G
authors.lastname: Vaniotis
authors.affiliation: Institut de Cardiologie de Montréal Centre de Recherche, Montréal, QC, Canada H1T 1C8 Département de Biochimie, Université de Montréal, Montréal, QC, Canada H3T 1J4 Département de Médecine, Université de Montréal, Montréal, QC, Canada H3T 1J4.
authors.forename: Bruce G
authors.initials: BG
authors.lastname: Allen
authors.affiliation: School of Biological Sciences, University of Reading, Whiteknights Campus, Reading, Berkshire RG6 6AS, UK.
authors.forename: Peter H
authors.initials: PH
authors.lastname: Sugden
authors.affiliation: School of Biological Sciences, University of Reading, Whiteknights Campus, Reading, Berkshire RG6 6AS, UK a.clerk@reading.ac.uk.
authors.forename: Angela
authors.initials: A
authors.lastname: Clerk
mesh_terms: D000818:Animals; D005260:Female; D020869:Gene Expression Profiling; D006333:Heart Failure / Q000201:enzymology*; D006801:Humans; D032383:Myocytes, Cardiac / Q000201:enzymology*; D011494:Protein Kinases / Q000235:genetics*; D040901:Proteomics; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D012333:RNA, Messenger; D011494:Protein Kinases
keywords: Cardiac myocytes; Heart; Human heart failure; Postnatal development; Protein kinases