Cys-loop Receptor Subunits

transmembrane structure of 
a cys-loop subunit The receptors of the cys-loop superfamily are made of five homologous subunits. Each subunit contains an extra-cellular amino-terminal domain, followed by four transmembrane segments. The loop located between TM3 and TM4 composes the intracellular domain, of variable length. The subunits of the cys-loop superfamily are distributed in two clear monophyletic groups, one containing the subunits forming anionic channels (GABAA and GABAC, Glycine, GLUCl, Histamine and 5HTmod1 receptors), and one containing the subunits forming cationic channels (5-HT3 and nicotinic receptors). Although site directed mutagenesis in the channel part succeded to invert selectivity, no example transgressing the frontier are know in nature. (If you are aware of one, please tell me!)

Available Sequences

Phylogenetic Studies


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Last modification: Wed Nov 24 10:59:05 GMT 2004 | Nicolas Le Novère