Castagna M, Palmer W K, Walsh D A
Eur J Biochem. 1975 Jun 16;55(1):193-9. doi: 10.1111/j.1432-1033.1975.tb02151.x.
Cytoplasmic and nuclear protein kinase activities from perfused rat liver have been studied in response to dibutyryl-adenosine cyclic 3':5'-monophosphate added at a concentration that stimulates hepatic gluconeogenesis (100 muM). Total nuclear protein kinase, as assayed using a mixed histone fraction as phosphate acceptor, is increased by 5-fold within 8 min of the addition of cyclic nucleotide to the perfusate. In contrast the total cytoplasmic protein kinase activity is decreased to 50% of the control value. The protein substrate specificity of the protein kinase that is present in the nucleus in response to dibutyryl-adenosine cyclic 3':5'-monophosphate stimulation is similar to that of cytoplasmic, adenosine cyclic 3':5'-monophosphate-dependent, protein kinase but is distinct from that of the enzyme(s) present in control nuclei. The predominant species to protein kinase from stimulated nuclei has a sedimentation constant of 3.9 S. This value is identical to that of the catalytic subunit of cytoplasmic adenosine 3':5'-monophosphate-dependent protein kinase. These data suggest that some of the effects of adenosine 3':5'-monophosphate on nuclear events may be mediated through its interaction with the inactive protein kinase holoenzyme in the cytoplasm and the subsequent redistribution of the active catalytic subunits generated by this interaction.
研究了灌注大鼠肝脏中细胞质和细胞核蛋白激酶活性对添加浓度为100μM、能刺激肝糖异生的二丁酰腺苷环3':5'-单磷酸的反应。以混合组蛋白部分作为磷酸受体进行测定，灌注液中添加环核苷酸后8分钟内，总细胞核蛋白激酶增加了5倍。相比之下，总细胞质蛋白激酶活性降至对照值的50%。响应二丁酰腺苷环3':5'-单磷酸刺激时，细胞核中存在的蛋白激酶的蛋白质底物特异性与细胞质中依赖腺苷环3':5'-单磷酸的蛋白激酶相似，但与对照细胞核中存在的酶不同。受刺激细胞核中的主要蛋白激酶种类沉降常数为3.9S。该值与细胞质腺苷3':5'-单磷酸依赖蛋白激酶的催化亚基相同。这些数据表明，腺苷3':5'-单磷酸对核事件的某些影响可能是通过其与细胞质中无活性蛋白激酶全酶的相互作用以及这种相互作用产生的活性催化亚基的后续重新分布来介导的。
