Coupling of adenosine A1 receptors to a G-protein in coated vesicles isolated from bovine brain: presence of pertussis and cholera toxin substrates

Abstract:

Adenosine A 1 receptors have been described in coated vesicles isolated from bovine brain (Gonzalez-Calero et al., J. Neurochem. 1990, 55, 106–113). Addition of non hydrolyzable GTP analogue (guanyl-5-yl-imidodiphosphate) caused a transition of the receptor from the high-to the low-affinity state, without any significant change in the total binding sites. The presence of G-proteins has been investigated by pertussis and cholera toxins catalyzed ADP-ribosylation. A band of Mr= 41,000 D, similar to the αGi subunit, was specifically labeled in the presence of preactivated pertussis toxin. Bands of Mr= 42,000 D and Mr= 47,000 D were specifically labeled in the presence of preactivated cholera toxin. These results confirm the presence of GTP binding proteins (αGi and αCs) in coated vesicles isolated from bovine brain.

Año de publicación:

1990

Keywords:

Fuente:

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