GABA Receptor B 1a, Rat (GBR1a) Control Peptide

An 18aa Peptide sequence near the N-terminus of rat GBR1a (1) was selected for antibody production. The peptide was coupled to KLH.

GABA (g-amino butyric acid) is the most abundant neurotransmitter in mammalian brain. GABA exerts its effects through ionotropic ligand-gated GABAA, GABAC and GABAB receptors (GABABRs). Presynaptic GABABRs inhibit neurotransmitter release by down regulating high voltage activated, Ca+2 channels, whereas postsynaptic GABABRs decrease neuronal excitability by activating a prominent inwardly rectifying K+ (Kir) conductance that underlies the late inhibitory postsynaptic potential.

Two N-terminal splice variants GABABR1 (also called GBR1), GABABR1a (GBR1a, rat 960 aa, apparent mol wt ~130kD; human 961 aa) and GABABR1b (GBR1b; rat 844 aa, apparent MW 100kD; human 844) have been cloned and characterized. Human and rat GBR1a and GBR1b share 99% sequence homology. GABABRs are characterized by the presence of a cleavable signal peptide, a large extracellular N-terminus, 7 TM domains, and C-terminal, cytoplasmic domain. GABABRs are expressed in all major areas of the brain. Recently GABABR2 (or GBR2) has been cloned from rat (940 aa) and human (941 aa). GBR2 forms heterodimer with GBR1 through interaction at the intracellular C-terminal regions. Heterodimerization appears to be important in transporting GBR1 to the membrane and expression of functional receptors. GBR2 also colocalized with GBR1.