Segal E D, Cha J, Lo J, Falkow S, Tompkins L S
Department of Microbiology, Stanford University, Stanford, CA 94305, USA.
Proc Natl Acad Sci U S A. 1999 Dec 7;96(25):14559-64. doi: 10.1073/pnas.96.25.14559.
Helicobacter pylori, present in half of the world's population, is a very successful pathogen. It can survive for decades in the human stomach with few obvious consequences to the host. However, it is also the cause of gastric diseases ranging from gastritis to ulcers to gastric cancer and has been classified a type 1 carcinogen by the World Health Organization. We have previously shown that phosphorylation of a 145-kDa protein and activation of signal transduction pathways are associated with the attachment of H. pylori to gastric cells. Here we identify the 145-kDa protein as the H. pylori CagA protein. We also show that CagA is necessary to induce a growth-factor-like phenotype (hummingbird) in host gastric cells similar to that induced by hepatocyte growth factor (HGF). Additionally, we identify a second cellular phenotype induced after attachment by H. pylori, which we call SFA (stress fiber associated). SFA is CagA independent and is produced by type I and type II H. pylori.
幽门螺杆菌存在于全球一半的人口中，是一种非常成功的病原体。它能在人类胃部存活数十年，对宿主几乎没有明显影响。然而，它也是从胃炎到溃疡再到胃癌等胃部疾病的病因，并且已被世界卫生组织列为1类致癌物。我们之前已经表明，一种145 kDa蛋白的磷酸化和信号转导通路的激活与幽门螺杆菌附着于胃细胞有关。在此，我们确定该145 kDa蛋白为幽门螺杆菌CagA蛋白。我们还表明，CagA对于在宿主胃细胞中诱导类似于肝细胞生长因子（HGF）所诱导的生长因子样表型（蜂鸟样）是必需的。此外，我们确定了幽门螺杆菌附着后诱导的第二种细胞表型，我们称之为SFA（应力纤维相关）。SFA不依赖CagA，由I型和II型幽门螺杆菌产生。
