Stübner D, Johnson R A
Department of Physiology and Biophysics, State University of New York, Stony Brook 11794-8661.
FEBS Lett. 1989 May 8;248(1-2):155-61. doi: 10.1016/0014-5793(89)80452-1.
The effects of forskolin on the sensitivity of adenylate cyclase to 'P'-site-mediated inhibition were studied. Stimulation of crude and purified preparations of adenylate cyclase by forskolin led to decreased sensitivity to inhibition by 2',5' dideoxyadenosine with enzyme from rat and bovine brain. This is in contrast with the enhancement of P-site sensitivity induced by calmodulin, divalent cations, and stable GTP analogs and is in contrast with behavior seen with enzyme from liver and S49 cyc membranes. The effect of forskolin on P-site sensitivity of the brain adenylate cyclase was not dependent on the presence of G-proteins or calmodulin. It was not the consequence of proteolysis nor was it due to an obvious artifact in the assay procedures. This distinct behavior of the brain enzyme is most likely due to a structural difference in the catalytic subunit.
研究了福斯高林对腺苷酸环化酶对‘P’位点介导抑制的敏感性的影响。福斯高林刺激大鼠和牛脑来源的腺苷酸环化酶粗提物和纯化制剂，导致对2'，5' -二脱氧腺苷抑制的敏感性降低。这与钙调蛋白、二价阳离子和稳定GTP类似物诱导的P位点敏感性增强相反，也与肝脏和S49 cyc膜来源的酶的情况相反。福斯高林对脑腺苷酸环化酶P位点敏感性的影响不依赖于G蛋白或钙调蛋白的存在。它不是蛋白水解的结果，也不是测定过程中明显假象导致的。脑酶的这种独特行为很可能是由于催化亚基的结构差异。
