RGS2 is a Feedback Inhibitor of Melatonin Production in the Pineal Gland.

The Section on Neuroendocrinology, Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, United States.
FEBS letters (Impact Factor: 3.34). 03/2013; 587(9). DOI: 10.1016/j.febslet.2013.03.016
Source: PubMed

ABSTRACT The 24-hour rhythmic production of melatonin by the pineal gland is essential for coordinating circadian physiology. Melatonin production increases at night in response to the release of norepinephrine from sympathetic nerve processes which innervate the pineal gland. This signal is transduced through G-protein-coupled adrenergic receptors. Here, we found that the abundance of Regulator of G-protein Signaling 2 (RGS2) increases at night, that expression is increased by norepinephrine and that this protein has a negative feedback effect on melatonin production. These data are consistent with the conclusion that RGS2 functions on a daily basis to negatively modulate melatonin production.

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