Hovanessian A G, Galabru J, Meurs E, Buffet-Janvresse C, Svab J, Robert N
Virology. 1987 Jul;159(1):126-36. doi: 10.1016/0042-6822(87)90355-2.
The double-stranded RNA-dependent protein kinase from human cells is a 68,000 molecular weight protein (p68 kinase), the level of which is enhanced significantly in cells treated with interferon. With a monoclonal antibody specific for p68 kinase, here we show the phosphorylation and steady-state levels of p68 kinase during virus infection. The p68 kinase is phosphorylated in interferon-treated cells during infection with encephalomyocarditis virus (EMCV), vesicular stomatitis virus (VSV), and vaccinia virus, thus indicating activation of p68 kinase during these virus infections, an essential step required for autophosphorylation of p68 kinase. However, in spite of this activation, the level of p68 kinase is rapidly decreased in virus-infected cells. The half-life of p68 kinase in uninfected cells is 6 to 7 hr, whereas in EMCV-infected cells it is 2 to 3 hr. This decrease in the level of p68 kinase is dependent on the multiplicity of virus infection and it seems to be specific since other cellular proteins as well as the activity of 2'-5'-oligoadenylate synthetase are not modified. Decreased levels of p68 kinase are also observed in cells infected with VSV and vaccinia virus. In the absence of virus infection, decreased levels of p68 kinase occur in cells following incubation with poly(I).poly(C).
人细胞中的双链RNA依赖性蛋白激酶是一种分子量为68,000的蛋白质（p68激酶），在用干扰素处理的细胞中其水平显著升高。利用针对p68激酶的单克隆抗体，我们在此展示了病毒感染期间p68激酶的磷酸化和稳态水平。在感染脑心肌炎病毒（EMCV）、水疱性口炎病毒（VSV）和痘苗病毒期间，p68激酶在经干扰素处理的细胞中被磷酸化，因此表明在这些病毒感染期间p68激酶被激活，这是p68激酶自身磷酸化所需的关键步骤。然而，尽管有这种激活，p68激酶的水平在病毒感染的细胞中迅速下降。未感染细胞中p68激酶的半衰期为6至7小时，而在EMCV感染的细胞中为2至3小时。p68激酶水平的这种下降取决于病毒感染的复数，并且似乎具有特异性，因为其他细胞蛋白以及2'-5'-寡腺苷酸合成酶的活性未被改变。在感染VSV和痘苗病毒的细胞中也观察到p68激酶水平降低。在没有病毒感染的情况下，用聚肌苷酸-聚胞苷酸（poly(I).poly(C)）孵育后的细胞中p68激酶水平降低。
