The glycine receptor is a ligand-gated anion channel protein, providing inhibitory drive within the nervous system. We report here the isolation and functional characterization of a novel alpha subunit (alpha-Z1) of the glycine receptor from adult zebrafish (Danio rerio) brain. The predicted amino acid sequence is 86%, 81% and 77% identical to mammalian isoforms alpha-1, alpha-3 and alpha-2, respectively. alpha-Z1 exhibits many of the molecular features of mammalian alpha-1, but the sequence patterns in the M4 and C-terminal domains are more similar to alpha-2/alpha-3. Phylogenetic analysis indicates that alpha-Z1 is more closely related to the mammalian alpha-l subunits, being positioned, however, on a distinct branch. The alpha-Z1 messenger RNA is 9.5 kb, similar to that described previously for alpha-1 messenger RNAs. When expressed in Xenopus oocytes or a human cell line (BOSC 23), alpha-Z1 forms a homomeric receptor which is activated by glycine and antagonized by strychnine. This receptor demonstrates unexpectedly high sensitivity to taurine and can also be activated by GABA. These results are consistent with physiological findings in lamprey and goldfish, and they suggest that this teleost fish glycine receptor displays a lower selectivity to neurotransmitters than that reported for glycine mammalian receptors. (C) 1999 IBRO. Published by Elsevier Science Ltd.
Cloning, expression and electrophysiological characterization of glycine receptor alpha subunit from zebrafish / B., David Watine; C., Goblet; D., De Saint Jan; Fucile, Sergio; V., Devignot; P., Bregestovski; H., Korn. - In: NEUROSCIENCE. - ISSN 0306-4522. - 90:1(1999), pp. 303-317. [10.1016/s0306-4522(98)00430-8]
Cloning, expression and electrophysiological characterization of glycine receptor alpha subunit from zebrafish
FUCILE, Sergio;
1999
Abstract
The glycine receptor is a ligand-gated anion channel protein, providing inhibitory drive within the nervous system. We report here the isolation and functional characterization of a novel alpha subunit (alpha-Z1) of the glycine receptor from adult zebrafish (Danio rerio) brain. The predicted amino acid sequence is 86%, 81% and 77% identical to mammalian isoforms alpha-1, alpha-3 and alpha-2, respectively. alpha-Z1 exhibits many of the molecular features of mammalian alpha-1, but the sequence patterns in the M4 and C-terminal domains are more similar to alpha-2/alpha-3. Phylogenetic analysis indicates that alpha-Z1 is more closely related to the mammalian alpha-l subunits, being positioned, however, on a distinct branch. The alpha-Z1 messenger RNA is 9.5 kb, similar to that described previously for alpha-1 messenger RNAs. When expressed in Xenopus oocytes or a human cell line (BOSC 23), alpha-Z1 forms a homomeric receptor which is activated by glycine and antagonized by strychnine. This receptor demonstrates unexpectedly high sensitivity to taurine and can also be activated by GABA. These results are consistent with physiological findings in lamprey and goldfish, and they suggest that this teleost fish glycine receptor displays a lower selectivity to neurotransmitters than that reported for glycine mammalian receptors. (C) 1999 IBRO. Published by Elsevier Science Ltd.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
