Inglis Diane O, Johnson Alexander D
Department of Biochemistry and Biophysics, University of California-San Francisco, San Francisco, California 94143, USA.
Mol Cell Biol. 2002 Dec;22(24):8669-80. doi: 10.1128/MCB.22.24.8669-8680.2002.
In response to a number of distinct environmental conditions, the fungal pathogen Candida albicans undergoes a morphological transition from a round, yeast form to a series of elongated, filamentous forms. This transition is believed to be critical for virulence in a mouse model of disseminated candidiasis. Here we describe the characterization of C. albicans ASH1, a gene that encodes an asymmetrically localized transcriptional regulatory protein involved in this response. We show that C. albicans ash1 mutants are defective in responding to some filament-inducing conditions. We also show that Ash1p is preferentially localized to daughter cell nuclei in the budding-yeast form of C. albicans cell growth and to the hyphal tip cells in growing filaments. Thus, Ash1p "marks" newly formed cells and presumably directs a specialized transcriptional program in these cells. Finally, we show that ASH1 is required for full virulence of C. albicans in a mouse model of disseminated candidiasis.
针对多种不同的环境条件，真菌病原体白色念珠菌会经历从圆形酵母形态到一系列细长丝状形态的形态转变。这种转变被认为在播散性念珠菌病小鼠模型的致病性中起关键作用。在此，我们描述了白色念珠菌ASH1的特征，该基因编码一种参与此反应的不对称定位转录调节蛋白。我们表明白色念珠菌ash1突变体在对某些诱导丝状化条件的反应中存在缺陷。我们还表明，Ash1p在白色念珠菌细胞生长的出芽酵母形态中优先定位于子细胞核，在生长的菌丝中定位于菌丝顶端细胞。因此，Ash1p“标记”新形成的细胞，并可能在这些细胞中指导特定的转录程序。最后，我们表明ASH1是白色念珠菌在播散性念珠菌病小鼠模型中完全致病所必需的。
