Abstract
Type-A receptors for the neurotransmitter GABA (γ-aminobutyric acid) are ligand-gated chloride channels that mediate inhibitory neurotransmission. Each subunit of the pentameric receptor protein has ligand-binding sites in the amino-terminal extracellular domain and four membrane-spanning regions, one of which forms a wall of the ion channel1. Each subunit also has a large intracellular loop that may be a target for protein kinases and be required for subcellular targeting and membrane clustering of the receptor, perhaps by anchoring the receptor to the cytoskeleton2,3,4. Neurotransmitter receptors need to be positioned in high density in the cell membrane at sites postsynaptic to nerve terminals releasing that neurotransmitter. Other members of the superfamily of ligand-gated ion-channel receptors associate in postsynaptic-membrane clusters by binding to the proteins rapsyn or gephyrin5,6,7. Here we identify a new cellular protein, GABAA-receptor-associated protein (GABARAP), which can interact with the γ2 subunit of GABAA receptors. GABARAP binds to GABAA receptors both in vitro and in vivo, and co-localizes with the punctate staining of GABAA receptors on cultured cortical neurons. Sequence analysis shows similarity between GABARAP and light chain-3 of microtubule-associated proteins 1A and 1B. Moreover, the N terminus of GABARAP is highly positively charged and features a putative tubulin-binding motif. The interactions among GABAA receptors, GABARAP and tubulin suggest a mechanism for the targeting and clustering of GABAA receptors.
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References
Macdonald, R. L. & Olsen, R. W. GABAAreceptor channels. Annu. Rev. Neurosci. 17, 569–602 (1994).
Leidenheimer, N. J., Browning, M. D. & Harris, R. A. GABAAreceptor phosphorylation: multiple sites, actions and artifacts. Trends Pharmacol. Sci. 12, 84–87 (1991).
Moss, S. J., Smart, T. G., Blackstone, C. D. & Huganir, R. L. Functional modulation of GABAAreceptors by cAMP-dependent protein phosphorylation. Science 257, 661–665 (1992).
Nusser, Z., Roberts, J. D., Baude, A., Richards, J. G. & Somogyi, P. Relative densities of synaptic and extrasynaptic GABAAreceptors on cerebellar granule cells as determined by a quantitative immunogold method. J. Neurosci. 15, 2948–2960 (1995).
Froehner, S. C. Regulation of ion channel distribution at synapses. Annu. Rev. Neurosci. 16, 347–368 (1993).
Carr, C., McCourt, D. & Cohen, J. B. The 43-kilodalton protein of Torpedo nicotinic postsynaptic membranes: purification and determination of primary structure. Biochemistry 26, 7090–7102 (1987).
Prior, P. et al. Primary structure and alternative splice variants of gephyrin, a putative glycine receptor-tubulin linker protein. Neuron 8, 1161–1170 (1992).
Zervos, A. S., Gyuris, J. & Brent, R. Mxi1, a protein that specifically interacts with Max to bind Myc-Max recognition sites. Cell 72, 223–232 (1993).
Fritschy, J. M. & Mohler, H. GABAA-receptor heterogeneity in the adult rat brain: differential regional and cellular distribution of seven major subunits. J. Comp. Neurol. 359, 154–194 (1995).
Moss, S. J., Doherty, C. A. & Huganir, R. L. Identification of the cAMP-dependent protein kinase and protein kinase C phosphorylation sites within the major intracellular domains of β1, γ2S and γ2L subunits of γ-aminobutyric acid type A receptor. J. Biol. Chem. 267, 14470–14476 (1992).
Mann, S. S. & Hammarback, J. A. Molecular characterization of light chain 3. J. Biol. Chem. 269, 11492–11497 (1994).
Maccioni, R. B. & Cambiazo, V. Role of microtubule-associated proteins in the control of microtubule assembly. Physiol. Rev. 75, 835–864 (1995).
Sanchez, C., Padilla, R., Paciucci, R., Zabala, J. C. & Avila, J. Binding of heat-shock protein 70 (hsp70) to tubulin. Arch. Biochem. Biophys. 310, 428–432 (1994).
Garnier, J., Osguthorpe, D. J. & Robson, B. Analysis of the accuracy and implications of simple methods for predicting the secondary structure of globular proteins. J. Mol. Biol. 120, 97–120 (1978).
Gao, B. & Fritschy, J. M. Selective allocation of GABAAreceptors containing the α1 subunit to neurochemically distinct subpopulations of rat hippocampal interneurons. Eur. J. Neurosci. 6, 837–853 (1994).
Hill, J. A. J Nicotinic receptor-associated 43K protein and progresive stabilization of the postsynaptic membrane. Mol. Neurobiol. 6, 1–17 (1992).
Langosch, D., Hoch, W. & Betz, H. The 93 kDa protein gephyrin and tubulin associated with the inhibitory glycine receptor are phosphorylated by an endogenous protein kinase. FEBS Lett. 298, 113–117 (1992).
Gillespie, K. H., Balasubramanian, S., Fung, E. T. & Huganir, R. L. Rapsyn clusters and activates the synapse-specific receptor tyrosine kinase MuSK. Neuron 16, 953–962 (1996).
Kannenberg, K., Baur, R. & Sigel, E. Proteins associated with alpha 1-subunit-containing GABAAreceptors from bovine brain. J. Neurochem. 68, 1352–1360 (1997).
Item, C. & Sieghart, W. Binding of gamma-aminobutyric acid A receptors to tubulin. J. Neurochem. 63, 1119–1125 (1994).
Nishimura, R. N. & Dwyer, B. E. Evidence for different mechanisms of induction of HSP70i: a comparison of cultured rat cortical neurons with astrocytes. Mol. Brain Res. 36, 227–239 (1996).
Acknowledgements
We thank R. Brent for the yeast two-hybrid system; K. Wilcox for pETNB plasmid; Z. Nusser and C. Houser for helpful discussion; and J. DeVellis and R. Cole for help with primary neuronal culture. This work is supported by an NIH grant (to R.W.O.) and an NIH training grant (to H.W.).
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Wang, H., Bedford, F., Brandon, N. et al. GABAA-receptor-associated protein links GABAA receptors and the cytoskeleton. Nature 397, 69–72 (1999). https://doi.org/10.1038/16264
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DOI: https://doi.org/10.1038/16264
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