Selective activation of G‐protein subtypes by vertebrate and invertebrate rhodopsins

FEBS Letters

Tachibanaki, Shuji¹  Terakita, Akihisa¹  Shichida, Yoshinori¹  Yamashita, Takahiro¹ 

[1] Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan

关键词: Rhodopsin;    Transducin;    Gq-type G-protein;    Phototransduction cascade;    Visual cell;    Gt;    transducin;    Gq;    Gq-type G-protein;    PLC;    phospholipase C;    G11;    G11 subclass of G-protein;    ROS;    rod outer segments;    SML;    sucrose monolaurate;    DM;    dodecylmaltoside;    HEPES;    N-(2-hydroxyethyl)piperazine-N′-2-ethanesulfonic acid;    DTT;    dithiothreitol;    PC;    l-α-phosphatidylcholine from egg yolk;    GTPγS;    guanosine 5′-O-(3-thiotriphosphate);    mACh;    muscarinic acetylcholine;   

DOI  :  10.1016/S0014-5793(98)01340-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We have quantitatively investigated specificities in activating G-protein subtype by bovine and squid rhodopsins to examine whether or not the phototransduction cascade in each of the photoreceptor cells is determined by the colocalization of a large amount of G-protein subtype (Gt or Gq). In contrast to the efficient activation of respective Gt and Gq, bovine and squid rhodopsins scarcely activated G-protein counterparts. Exchange of α- and βγ-subunits of Gt and Gq indicated the critical role of the α-subunit in specific binding to respective rhodopsins. Thus the specific recognition of G-protein subtype by each rhodopsin is a major mechanism in determining the phototransduction cascade.

【 授权许可】

Unknown