Beschreibung:
<p> The distribution in chicken retina of the α subunit of transducin, the guanine nucleotide-binding protein that couples light-dependent activation of rhodopsin with activation of guanosine 3′,5′-monophosphate phosphodiesterase, was determined with the aid of a specific antiserum. α-Transducin was found in rod photoreceptor cells but was not detected in cones. These results show that rods and cones differ with respect to α-transducin content and suggest that the processes of phototransduction may differ correspondingly in rods and cones. </p>