Hydroxycarboxylic acid receptor 1

Hydroxycarboxylic acid receptor 1 (HCA1), also known as GPR81, is a protein that in humans is encoded by the HCAR1 gene. It is a member of the hydroxycarboxylic acid receptor family, which is a group of G protein-coupled receptors. HCA1 is primarily expressed in adipose tissue and is involved in the regulation of lipolysis and energy homeostasis.

Structure

File:G protein-coupled receptor.png

A generic structure of a G protein-coupled receptor, which HCA1 is a member of.

The HCA1 protein is a member of the G protein-coupled receptor family, which are characterized by seven transmembrane domains. The protein is encoded by the HCAR1 gene, which is located on chromosome 12 in humans. The gene spans approximately 5.3 kilobases and consists of two exons.

Function

HCA1 is primarily expressed in adipose tissue, where it plays a crucial role in the regulation of lipolysis, the breakdown of fats and other lipids to release fatty acids. The receptor is activated by lactate, a product of anaerobic metabolism. Upon activation, HCA1 inhibits the activity of adenylate cyclase, leading to a decrease in cyclic AMP levels and a subsequent inhibition of lipolysis.

Clinical significance

Alterations in the function or expression of HCA1 have been implicated in various health conditions, including obesity, diabetes, and cardiovascular disease. As such, HCA1 is considered a potential therapeutic target for these conditions.

See also

• Hydroxycarboxylic acid receptor
• G protein-coupled receptor
• Adipose tissue
• Lipolysis