TRPC6 fulfills a calcineurin signaling circuit during pathologic cardiac remodeling.
The heart responds to injury and chronic pressure overload by pathologic growth and remodeling, which frequently result in heart failure and sudden death. Calcium-dependent signaling pathways promote cardiac growth and associated changes in gene expression in response to stress. The calcium/calmodulin-dependent phosphatase calcineurin, which signals to nuclear factor of activated T cells (NFAT) transcription factors, serves as a transducer of calcium signals and is sufficient and necessary for pathologic cardiac hypertrophy and remodeling. Transient receptor potential (TRP) proteins regulate cation entry into cells in response to a variety of signals, and in skeletal muscle, expression of TRP cation channel, subfamily C, member 3 (TRPC3) is increased in response to neurostimulation and calcineurin signaling. Here we show that TRPC6 was upregulated in mouse hearts in response to activated calcineurin and pressure overload, as well as in failing human hearts. Two conserved NFAT consensus sites in the promoter of the TRPC6 gene conferred responsiveness to cardiac stress. Cardiac-specific overexpression of TRPC6 in transgenic mice resulted in heightened sensitivity to stress, a propensity for lethal cardiac growth and heart failure, and an increase in NFAT-dependent expression of beta-myosin heavy chain, a sensitive marker for pathologic hypertrophy. These findings implicate TRPC6 as a positive regulator of calcineurin-NFAT signaling and a key component of a calcium-dependent regulatory loop that drives pathologic cardiac remodeling.
Kuwahara
Koichiro
K
Department of Molecular Biology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390-9148, USA.
Wang
Yanggan
Y
McAnally
John
J
Richardson
James A
JA
Bassel-Duby
Rhonda
R
Hill
Joseph A
JA
Olson
Eric N
EN
D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D019703:Calcineurin / Q000235:genetics / Q000378:metabolism*; D009202:Cardiomyopathies / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D002478:Cells, Cultured; D006333:Heart Failure / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D008822:Mice, Transgenic; D008954:Models, Biological; D008969:Molecular Sequence Data; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D018995:Myosin Heavy Chains / Q000235:genetics / Q000378:metabolism; D050778:NFATC Transcription Factors / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D034622:RNA Interference; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology*; D050052:TRPC Cation Channels / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D014157:Transcription Factors / Q000378:metabolism; D015533:Transcriptional Activation
C000594638:MYH7 protein, rat; D050778:NFATC Transcription Factors; D050052:TRPC Cation Channels; D014157:Transcription Factors; C492145:Trpc6 protein, rat; D019703:Calcineurin; D018995:Myosin Heavy Chains