Author(s): Wickman KD, Iniguez-Lluhl JA, Davenport PA, Taussig R, Krapivinsky GB, et al.
ACETYLCHOLINE activates inwardly rectifying potassium channels (Ik.ACh) in the heart1 through muscarinic receptor binding and activation of pertussis-toxin-sensitive G proteins2,3. Experiments showing that only the βγ-subunit (Gβγ) activates IK.ACH (ref. 4) were challenged by reports that only the activated α-subunit (Gα) was effective5. Here we examine IK.ACh regulation using purified brain and recombinant G-protein subunits. Six recombinant Gβγ-subunits activated IK.ACh with apparent half-maximal activation concentrations of 3-30 nM. Activation of IK.ACh by recombinant Gα-GTPγS was observed, but this was probably due to release of GTPγS from the protein. Importantly, IK.ACh activity elicited by GTPγS was inhibited by purified brain and recombinant Gα-GDP, suggesting that native Gβγ plays a major role in this pathway. We conclude that Gβγ is a primary regulator of IK.ACh activity.
Referred From: https://www.nature.com/articles/368255a0
Author(s): Murphy MP, LeVine H
Author(s): Kalaria RN, Andorn AC, Tabaton M, Whitehouse PJ, Harik SI, et al.
Author(s): Yu JT, Tan L, Ou JR, Zhu JX, Liu K, et al.
Author(s): Ni Y, Zhao X, Bao G, Zou L, Teng L, et al.
Author(s): Wang D, Fu Q, Zhou Y, Xu B, Shi Q, et al.
Author(s): Wisely EV, Xiang YK, Oddo S3
Author(s): Gelber RP, Ross GW, Petrovitch H, Masaki KH, Launer LJ, et al.
Author(s): White LR, Gelber RP, Launer LJ, Zarow C, Sonnen J, et al.
Author(s): Gelber RP, Ross GW, Petrovitch H, Masaki KH, Launer LJ, et al.
Author(s): Dupre DJ, Herbert TE, Jockers R
Author(s): Wang D, Yuen EY, Zhou Y, Yan Z, Xiang YK
Author(s): Gloerich M, Bos JL
Author(s): Clapham DE, Neer EJ
Author(s): Kim D, Lewis DL, Graziadei L, Neer EJ, Bar-Sagi D, et al.
Author(s): Khan SM, Sleno R, Gora S, Zylbergold P, Laverdure JP, et al.
Author(s): Wang D, Govindaiah G, Liu R, De Arcangelis V, Cox CL, et al.
Author(s): Oakley H, Cole SL, Logan S, Maus E, Shao P, et al.
Author(s): Storey JD, Tibshirani R
Author(s): Burns A, Iliffe S
Author(s): Kawas CH
Author(s): Ballard C, Gauthier S, Corbett A, Brayne C, Aarsland D, et al.
Author(s): Yankner BA, Duffy LK, Kirschner DA
Author(s): Lesne SE, Sherman MA, Grant M, Kuskowski M, Schneider JA, et al.
Author(s): Mc Donald JM, Savva GM, Brayne C, Welzel AT, Forster G, et al.
Author(s): Wang D, Xiang YK
Author(s): Luong K, Nguyen LT
Author(s): Ross JA, McGonigle P1, Van Bockstaele EJ
Author(s): Storey JD, Tibshirani R
Author(s): Münz C
Author(s): Aderem A, Underhill DM