title: Simultaneous loss of phospholipase Cδ1 and phospholipase Cδ3 causes cardiomyocyte apoptosis and cardiomyopathy.
abstract: Phospholipase C (PLC) is a key enzyme in phosphoinositide turnover. Among 13 PLC isozymes, PLCδ1 and PLCδ3 share high sequence homology and similar tissue distribution, and are expected to have functional redundancy in many tissues. We previously reported that the simultaneous loss of PLCδ1 and PLCδ3 caused embryonic lethality because of excessive apoptosis and impaired vascularization of the placenta. Prenatal death of PLCδ1/PLCδ3 double-knockout mice hampered our investigation of the roles of these genes in adult animals. Here, we generated PLCδ1/PLCδ3 double-knockout mice that expressed PLCδ1 in extra-embryonic tissues (cDKO mice) to escape embryonic lethality. The cDKO mice were born at the expected Mendelian ratio, which indicated that the simultaneous loss of PLCδ1 and PLCδ3 in the embryo proper did not impair embryonic development. However, half of the cDKO mice died prematurely. In addition, the surviving cDKO mice spontaneously showed cardiac abnormalities, such as increased heart weight/tibial length ratios, impaired cardiac function, cardiac fibrosis, dilation, and hypertrophy. Predating these abnormalities, excessive apoptosis of their cardiomyocytes was observed. In addition, siRNA-mediated simultaneous silencing of PLCδ1 and PLCδ3 increased apoptosis in differentiated-H9c2 cardiomyoblasts. Activation of Akt and protein kinase C (PKC) θ was impaired in the hearts of the cDKO mice. siRNA-mediated simultaneous silencing of PLCδ1 and PLCδ3 also decreased activated Akt and PKCθ in differentiated-H9c2 cardiomyoblasts. These results indicate that PLCδ1 and PLCδ3 are required for cardiomyocyte survival and normal cardiac function.
authors.affiliation: 1] Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan [2] CREST, JST, Kawaguchi, Saitama, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Nakamura
authors.affiliation: 1] Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan [2] CREST, JST, Kawaguchi, Saitama, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Kanemaru
authors.affiliation: Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Kojima
authors.affiliation: Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Hashimoto
authors.affiliation: Department of Molecular and Cellular Pharmacology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Marunouchi
authors.affiliation: Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Oka
authors.affiliation: Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ogura
authors.affiliation: Department of Molecular and Cellular Pharmacology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tanonaka
authors.affiliation: 1] Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan [2] CREST, JST, Kawaguchi, Saitama, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Fukami
mesh_terms: D000818:Animals; D017209:Apoptosis; D006332:Cardiomegaly / Q000201:enzymology / Q000235:genetics / Q000473:pathology; D009202:Cardiomyopathies / Q000201:enzymology* / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D002454:Cell Differentiation; D002460:Cell Line; D002470:Cell Survival; D004789:Enzyme Activation; D005355:Fibrosis; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D020022:Genetic Predisposition to Disease; D007527:Isoenzymes / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D032383:Myocytes, Cardiac / Q000201:enzymology* / Q000473:pathology; D010641:Phenotype; D054803:Phospholipase C delta / Q000172:deficiency* / Q000235:genetics; D011493:Protein Kinase C / Q000378:metabolism; D000074121:Protein Kinase C-theta; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D034622:RNA Interference; D051381:Rats; D013997:Time Factors; D014162:Transfection
chemical_list: D007527:Isoenzymes; D051057:Proto-Oncogene Proteins c-akt; C489593:Prkcq protein, mouse; D011493:Protein Kinase C; D000074121:Protein Kinase C-theta; D054803:Phospholipase C delta; C518025:Plcd1 protein, mouse; C518026:Plcd1 protein, rat; C518029:Plcd3 protein, mouse