Unitat de Recerca. Hospital Universitari Joan XXIII, IISPV, Tarragona, Spain.
Mol Microbiol. 2011 Apr;80(2):423-35. doi: 10.1111/j.1365-2958.2011.07585.x. Epub 2011 Mar 3.
Quiescence is an essential process in eukaryotes. Control of cell cycle progression by stress-activated protein kinases (SAPK) is critical for cell adaptation to extracellular stimuli. In yeast, activation of the HOG MAPK signalling pathway results in the control of cell cycle at several phases. In this manuscript, we describe the role of Hog1p modulating re-entry into cell cycle from a resting state. Cells deficient in Hog1p activation show a delay in entering the mitotic cell cycle from the stationary phase. Furthermore, a repressible Hog1p allele (Hog1AS) presents a comparable behaviour at this phase to the deleted strain. In addition, the role of Hog1p at the stationary phase exit is not related to loss of cell viability. Moreover, when cells enter the mitotic cell cycle after being in the stationary phase, Hog1p is rapidly activated and concentrates in the nucleus where it modifies the expression of several genes. Similar results are obtained in higher eukaryotic cells by activation of p38. Thus, these results reveal a novel role of the SAPK Hog1p in the control of cell cycle progression as cells leave a resting state.
静息是真核生物的一个基本过程。应激激活蛋白激酶（SAPK）对细胞周期进程的控制对于细胞适应细胞外刺激至关重要。在酵母中，HOG MAPK 信号通路的激活导致细胞周期在几个阶段受到控制。在本手稿中，我们描述了 Hog1p 在调节从静止状态重新进入细胞周期中的作用。Hog1p 激活缺失的细胞显示出从停滞期进入有丝分裂细胞周期的延迟。此外，可阻遏的 Hog1p 等位基因（Hog1AS）在该阶段表现出与缺失菌株相当的行为。此外，Hog1p 在静止期退出时的作用与细胞活力的丧失无关。此外，当细胞从停滞期进入有丝分裂细胞周期时，Hog1p 被迅速激活并集中在细胞核中，在那里它修饰了几个基因的表达。通过激活 p38 在高等真核细胞中获得类似的结果。因此，这些结果揭示了 SAPK Hog1p 在控制细胞离开静止状态时的细胞周期进程中的新作用。
