GABRD


Gamma-aminobutyric acid receptor subunit delta is a protein that in humans is encoded by the GABRD gene.

Function

is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABAA receptors, which are ligand-gated chloride channels. The GABAA receptor is generally pentameric. Its five subunits are alpha, beta, gamma, delta, and rho. The GABRD gene encodes the delta subunit. Specifically, the δ-subunit is usually expressed in GABAA receptors associated with extrasynaptic activity. The most common GABAA receptors have the gamma subunit, which allows the receptor to bind benzodiazepines. For this reason, receptors containing δ-subunits are sometimes referred to as “benzodiazepine insensitive” GABAA receptors. The δ-subunit containing receptors are also known to be involved in the ventral tegmental area pathway in the brain's hippocampus, which means that they may have implications in learning, memory, and reward.

Cell type-specific expression

In a technical comparison between quantitative reverse transcriptase PCR and digital PCR, the expression of the rat gabrd gene was examined across three cell types in the somatosensory cortex: neurogliaform cells, fast spiking basket cells and pyramidal cells. Gene expression was detected in all three cell types, but showed marked enrichment in neurogliaform cells versus the other cell types examined. The GABAA receptor delta subunit is profoundly downregulated with chronic intermittent exposure to ethanol, and appears to contribute strongly to pathological alcohol dependence.