Meinkoth J L, Alberts A S, Went W, Fantozzi D, Taylor S S, Hagiwara M, Montminy M, Feramisco J R
Department of Medicine, University of California at San Diego, La Jolla 92093-0636.
Mol Cell Biochem. 1993 Nov;127-128:179-86. doi: 10.1007/BF01076769.
Temporal cellular events responsible for hormonal activation of responses mediated by the cAMP-dependent protein kinase (PKA) have been studied in living cells. By selectively perturbing molecular function of Gs, the catalytic subunit of PKA (C), or the nuclear factor CREB, in cells through microinjection of inhibitory agents specific for these molecules or activated forms of these molecules, we have obtained evidence for a requirement for the function of each of these molecules in the hormonal stimulation of cAMP-regulated genes. Moreover, by introducing fluorescently labeled PKA subunits into these cells as molecular tracers, or by immunofluorescence of C subunit, we have observed biological translocation of C subunit from the cytoplasm to the nucleus during transcriptional activation and a quenching of this by the inhibitor molecule, PKI. The implications of these cellular and molecular events in the signal transduction of hormonal responses are discussed.
在活细胞中研究了负责由环磷酸腺苷（cAMP）依赖性蛋白激酶（PKA）介导的激素激活反应的时间性细胞事件。通过微注射针对这些分子或其活化形式的特异性抑制剂，选择性地干扰细胞中Gs、PKA催化亚基（C）或核因子CREB的分子功能，我们获得了证据，证明这些分子中的每一个在激素刺激cAMP调节基因中发挥功能是必需的。此外，通过将荧光标记的PKA亚基作为分子示踪剂引入这些细胞，或通过C亚基的免疫荧光，我们观察到在转录激活过程中C亚基从细胞质向细胞核的生物学易位，以及抑制剂分子PKI对其的淬灭作用。讨论了这些细胞和分子事件在激素反应信号转导中的意义。
