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  • The EMBO Journal (2000) 19, 6341 - 6350
  • doi:10.1093/emboj/19.23.6341

The MEK1–ERK1/2 signaling pathway promotes compensated cardiac hypertrophy in transgenic mice

Orlando F. Bueno1, Leon J. De Windt1, Kevin M. Tymitz1, Sandra A. Witt1, Thomas R. Kimball1, Raisa Klevitsky1, Timothy E. Hewett1, Steven P. Jones2, David J. Lefer2, Chang-Fu Peng3, Richard N. Kitsis3 and Jeffery D. Molkentin1

  1. Department of Pediatrics, University of Cincinnati, Division of Molecular Cardiovascular Biology, Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229-3039 USA
  2. Department of Molecular and Cellular Physiology, LSU Health Sciences Center, Shreveport, LA 71130 USA
  3. Departments of Medicine and Cell Biology, Einstein College of Medicine, The Bronx, NY 10461, USA

Correspondence to:

Jeffery D. Molkentin, E-mail: jeff.molkentin@chmcc.org

Received 23 June 2000; Accepted 9 October 2000; Revised 9 October 2000

Members of the mitogen-activated protein kinase (MAPK) cascade such as extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 are implicated as important regulators of cardiomyocyte hypertrophic growth in culture. However, the role that individual MAPK pathways play in vivo has not been extensively evaluated. Here we generated nine transgenic mouse lines with cardiac-restricted expression of an activated MEK1 cDNA in the heart. MEK1 transgenic mice demonstrated concentric hypertrophy without signs of cardiomyopathy or lethality up to 12 months of age. MEK1 transgenic mice showed a dramatic increase in cardiac function, as measured by echocardiography and isolated working heart preparation, without signs of decompensation over time. MEK1 transgenic mice and MEK1 adenovirus-infected neonatal cardiomyocytes each demonstrated ERK1/2, but not p38 or JNK, activation. MEK1 transgenic mice and MEK1 adenovirus-infected cultured cardiomyocytes were also partially resistant to apoptotic stimuli. The results of the present study indicate that the MEK1–ERK1/2 signaling pathway stimulates a physiologic hypertrophy response associated with augmented cardiac function and partial resistance to apoptotsis.

  • Keywords:

    • cardiac,
    • cardiomyopathy,
    • hypertrophy,
    • MAPK,
    • transgenic