Interaction of small G proteins with photoexcited rhodopsin

FEBS Letters

Jakobs, Karl H.¹  Ulibarri, Isabel¹  Gierschik, Peter¹  Wieland, Thomas¹  Aktories, Klaus² 

[1] Pharmakologisches Institut der Universität Heidelberg, Im Neuenheimer Feld 366, D-6900 Heidelberg FRG;Rudolf-Buchheim-Institut für Pharmakologie, Universität Giessen, D-4300 Giessen, FRG

关键词: GTP-binding protein;    Rhodopsin;    Botulinum C3 ADP-ribosyl-transferase;    Transducin;    (Bovine rod outer segment);   

DOI  :  10.1016/0014-5793(90)81372-U

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Bovine rod outer segment (ROS) membranes contain in addition to the heterotrimeric G protein transducin, several small GTP-binding proteins (23–27 kDa). Furthermore, these membranes contain two substrate proteins (about 22 and 24 kDa) for botulinum C3 ADP-ribosyltransferase known to ADP-ribosylate small G proteins in any mammalian cell type studied so far. Most interestingly, [³²P]ADP-ribosylation of ROS membrane small G proteins by C3 is regulated by light and guanine nucleotides in a manner similar to pertussis toxin-catalyzed [³²P]ADP-ribosylation of the α-subunit of transducin. These findings suggest that not only the heterotrimeric G protein transducin but also the C3 substrate small G proteins present in ROS membranes interact with photoexcited rhodopsin and thus contribute to its signalling action.

【 授权许可】

Unknown