Shyng S L, Nichols C G
Department of Cell Biology and Physiology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA.
Science. 1998 Nov 6;282(5391):1138-41. doi: 10.1126/science.282.5391.1138.
Adenosine triphosphate (ATP)-sensitive potassium (KATP) channels couple cell metabolism to electrical activity. Phosphatidylinositol phosphates (PIPs) profoundly antagonized ATP inhibition of KATP channels when applied to inside-out membrane patches. It is proposed that membrane-incorporated PIPs can bind to positive charges in the cytoplasmic region of the channel's Kir6.2 subunit, stabilizing the open state of the channel and antagonizing the inhibitory effect of ATP. The tremendous effect of PIPs on ATP sensitivity suggests that in vivo alterations of membrane PIP levels will have substantial effects on KATP channel activity and hence on the gain of metabolism-excitation coupling.
三磷酸腺苷（ATP）敏感性钾（KATP）通道将细胞代谢与电活动联系起来。当应用于内向外膜片时，磷脂酰肌醇磷酸（PIPs）能显著拮抗ATP对KATP通道的抑制作用。有人提出，掺入膜中的PIPs可与通道Kir6.2亚基胞质区域的正电荷结合，稳定通道的开放状态并拮抗ATP的抑制作用。PIPs对ATP敏感性的巨大影响表明，体内膜PIP水平的改变将对KATP通道活性产生实质性影响，进而对代谢-兴奋偶联增益产生影响。
