Kruppa Michael, Calderone Richard
Department of Microbiology & Immunology, Georgetown University Medical Center, Washington DC 20057, USA.
FEMS Yeast Res. 2006 Mar;6(2):149-59. doi: 10.1111/j.1567-1364.2006.00024.x.
Signal transduction pathways provide mechanisms for adaptation to stress conditions. One of the most studied of these pathways is the HOG1 MAP kinase pathway that in Saccharomyces cerevisiae is used to adapt cells to osmostress. The HOG1 MAPK has also been studied in Candida albicans, and more recently observations on the Hog1p functions have been described in two other human pathogens, Aspergillus fumigatus and Cryptococcus neoformans. The important, but not surprising, concept is that this pathway is used for different yet similar functions in each of these fungi, given their need to adapt to different environmental signals. Current studies of C. albicans focus upon the identification of two-component signal proteins that, in both C. albicans and S. cerevisiae, regulate the HOG1 MAPK. In C. albicans, these proteins regulate cell wall biosynthesis (and, therefore, adherence to host cells), osmotic and oxidant adaptation, white-opaque switching, morphogenesis, and virulence of the organism.
信号转导通路为适应应激条件提供了机制。这些通路中研究最多的之一是HOG1丝裂原活化蛋白激酶（MAP激酶）通路，在酿酒酵母中该通路用于使细胞适应渗透压应激。HOG1 MAPK也已在白色念珠菌中得到研究，最近在另外两种人类病原体烟曲霉和新型隐球菌中也描述了关于Hog1p功能的观察结果。重要但并不令人惊讶的概念是，鉴于这些真菌各自需要适应不同的环境信号，该通路在每种真菌中用于不同但相似的功能。目前对白色念珠菌的研究集中在鉴定双组分信号蛋白，在白色念珠菌和酿酒酵母中，这些蛋白都调节HOG1 MAPK。在白色念珠菌中，这些蛋白调节细胞壁生物合成（因此也调节对宿主细胞的粘附）、渗透压和氧化剂适应、白色-不透明转换、形态发生以及该生物体的毒力。
