ADRA2A
ADRA2A (adrenoceptor alpha 2A, also known as ADRAR, ADRA2 and ADRA2R) is a G protein-coupled receptor for catecholamines. It couples to the G(i/o) pathway to inhibit adenylyl cyclase and to restrain neurotransmitter release from noradrenergic nerve terminals. Browse Assay Genie's current range of ADRA2A research reagents below, or read on for the biology behind the target.
ADRA2A is an alpha-2 adrenergic receptor, a G protein-coupled receptor that binds catecholamines such as epinephrine and norepinephrine and activates the G(i/o) protein pathway. Downstream effects include inhibition of adenylyl cyclase, stimulation of ERK1/2 and suppression of voltage-gated calcium channels. Through these routes alpha-2 receptors help control physiological processes including regulation of blood pressure, lipolysis and insulin release.
A defining role of ADRA2A is presynaptic feedback inhibition of neurotransmitter release from noradrenergic nerve terminals in the sympathetic and central nervous systems. ADRA2A inhibits transmitter release at high stimulation frequencies, whereas ADRA2C modulates neurotransmission at lower levels of nerve activity. Studies in mouse indicate that both the alpha2A and alpha2C subtypes are required for presynaptic transmitter release from the sympathetic nervous system in the heart and from central noradrenergic neurons. The sympathetic nervous system regulates cardiovascular function by activating adrenergic receptors in the heart, blood vessels and kidney.
The ADRA2A gene encodes a plasma membrane protein belonging to the G protein-coupled receptor 1 family, adrenergic receptor subfamily, and the HGNC adrenoceptor gene group. It is one of three highly homologous alpha-2 subtypes (alpha2A, alpha2B and alpha2C), and orthologues are annotated in mouse and rat as Adra2a. Pharmacologically, the agonist rank order of potency is oxymetazoline > clonidine > epinephrine > norepinephrine, while yohimbine is the most potent antagonist listed, followed by phentolamine and mianserine. A clear association between alpha-2-adrenergic receptors and disease has not yet been established.
ADRA2A mediates presynaptic feedback inhibition of neurotransmitter release from noradrenergic terminals in sympathetic and central nervous systems.
Alpha-2 receptors contribute to blood pressure regulation, and sympathetic control of the heart, blood vessels and kidney acts through adrenergic receptors.
ADRA2A couples to G(i/o) to inhibit adenylyl cyclase, stimulate ERK1/2 and suppress voltage-gated calcium channels.
Alpha-2 adrenergic receptors help control lipolysis and insulin release, making ADRA2A relevant to studies of metabolic regulation.
ADRA2A is a catecholamine-binding G protein-coupled receptor that activates G(i/o) signalling, inhibiting adenylyl cyclase, stimulating ERK1/2 and suppressing voltage-gated calcium channels. It mediates presynaptic feedback inhibition of noradrenergic neurotransmitter release, particularly at high stimulation frequencies.
HGNC names the gene adrenoceptor alpha 2A; UniProt calls the protein alpha-2A adrenergic receptor. Aliases and previous symbols include ADRAR, ADRA2 and ADRA2R, and an earlier name was adrenergic, alpha-2A-, receptor. It is also referred to as the alpha2A subtype.
Mouse and rat both have an Adra2a orthologue, and mouse studies show alpha2A and alpha2C are needed for presynaptic transmitter release. NCBI Gene notes that a clear association between alpha-2-adrenergic receptors and disease has not yet been established. Check the datasheet of any product for its validated reactivity.
Other adrenoceptors that share catecholamine signalling and neurotransmitter-release roles with ADRA2A.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P08913; product specifications from Assay Genie datasheets.