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Published on: March 31, 2012
RGS3 and RGS4 are GTPase activating proteins in the heart
1Center for Cardiovascular Research, Department of Medicine, Washington University School of Medicine, St Louis, MO 63110, USA.
Regulator of G protein signaling (RGS) proteins, RGS3 and RGS4, are found in the heart and their expression changes with cardiac hypertrophy and failure. These findings suggest RGS proteins are key regulators of cardiac function.
Area of Science:
- Molecular biology
- Cardiovascular physiology
- Biochemistry
Background:
- Regulator of G protein signaling (RGS) proteins function as GTPase activating proteins (GAPs) for G alpha subunits.
- RGS proteins deactivate Gi alpha, Go alpha, and Gq alpha G protein subtypes.
- The role of RGS proteins in cardiac physiology is largely unknown.
Purpose of the Study:
- To investigate the expression patterns of RGS3 and RGS4 in normal and diseased rat heart tissue.
- To evaluate the role of RGS family members in cardiac physiology regulation.
Main Methods:
- Detection of RGS3 and RGS4 mRNAs and proteins in adult rat myocardium.
- Analysis of RGS gene expression in cultured neonatal rat cardiomyocytes stimulated with growth factors.
- Assessment of RGS gene expression in pulmonary artery-banded (PAB) mice.
- Examination of RGS mRNA levels in failing myocardium from SHHF rats.
Main Results:
- RGS3 and RGS4 mRNAs and proteins were detected in adult rat myocardium.
- RGS3 and RGS4 gene expression was significantly increased in models of cardiac hypertrophy.
- RGS3 and RGS4 mRNA levels were decreased in failing myocardium.
Conclusions:
- RGS gene expression is highly regulated in the myocardium.
- RGS family members likely play a significant role in regulating cardiac function.
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