Gabbr2 phospho S783
Developmental stage
On the day of birth, expressed in the regions of the brain including hippocampus, thalamic nuclei and cortex (PubMed:9872744). Abundant in brain cortex and cerebellum throughout postnatal development whereas its expression in spinal cord gradually decreases (PubMed:9872317).
Domain
Alpha-helical parts of the C-terminal intracellular region mediate heterodimeric interaction with GABA-B receptor 1.
Function
Component of a heterodimeric G-protein coupled receptor for GABA, formed by GABBR1 and GABBR2 (PubMed:9872315, PubMed:9872317, PubMed:9872744). Within the heterodimeric GABA receptor, only GABBR1 seems to bind agonists, while GABBR2 mediates coupling to G proteins (PubMed:10658574, PubMed:9872317). Ligand binding causes a conformation change that triggers signaling via guanine nucleotide-binding proteins (G proteins) and modulates the activity of down-stream effectors, such as adenylate cyclase (PubMed:10075644, PubMed:10924501, PubMed:9872315, PubMed:9872317, PubMed:9872744, Ref.4). Signaling inhibits adenylate cyclase, stimulates phospholipase A2, activates potassium channels, inactivates voltage-dependent calcium-channels and modulates inositol phospholipid hydrolysis (PubMed:10457184, PubMed:10924501, PubMed:9872315, PubMed:9872317, PubMed:9872744). Plays a critical role in the fine-tuning of inhibitory synaptic transmission (PubMed:10457184, PubMed:9872317, PubMed:9872744). Pre-synaptic GABA receptor inhibits neurotransmitter release by down-regulating high-voltage activated calcium channels, whereas postsynaptic GABA receptor decreases neuronal excitability by activating a prominent inwardly rectifying potassium (Kir) conductance that underlies the late inhibitory postsynaptic potentials (PubMed:10924501, PubMed:9872744). Not only implicated in synaptic inhibition but also in hippocampal long-term potentiation, slow wave sleep, muscle relaxation and antinociception (By similarity).
Sequence Similarities
Belongs to the G-protein coupled receptor 3 family. GABA-B receptor subfamily.
Tissue Specificity
Highly expressed in areas of the brain including thalamic nuclei, the hippocampus, cerebellar Purkinje cells and the medial habenula, and moderately expressed in the cerebral cortex, certain anterioventral thalamic nuclei, dorsal medial hypothalamic nucleus and suprachiasmatic nuclei (PubMed:10727622, PubMed:9872315, PubMed:9872317, PubMed:9872744). Also weakly expressed in the testis (PubMed:9872744).
Cellular localization
- Cell membrane
- Multi-pass membrane protein
- Postsynaptic cell membrane
- Multi-pass membrane protein
- Perikaryon
- Cell projection
- Dendrite
- Coexpression of GABBR1 and GABBR2 is required for GABBR1 maturation and transport to the plasma membrane (PubMed:10457184). In contrast, GABBR2 does not depend on GABBR1 for transport to the cell membrane.
Alternative names
Gpr51, Gamma-aminobutyric acid type B receptor subunit 2, GABA-B receptor 2, GABA-B-R2, GABA-BR2, GABABR2, Gb2, G-protein coupled receptor 51