Cao Fang, Chen Jiang Ye
State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institute for Biological Science, Chinese Academy of Sciences, Shanghai 200031, China.
Shi Yan Sheng Wu Xue Bao. 2005 Apr;38(2):119-25.
The dimorphic transition of yeast and hyphal forms is one of most determinants in Candida albicans for its pathogenicity. This transition is regulated by several signal transduction pathways. Transcriptional factor Flo8 plays an important role in morphogenesis of Saccharomyces cerevisiae. In this work, a C. albicans genomic DNA library was introduced into a S. cerevisiae flo8/flo8 mutant and genes which could suppress invasive growth defect were isolated. A novel gene was isolated and designated CaPPE1 (Candida albicans PPE1 gene). CaPPE1 encoded for a 361 amino acid protein CaPpe1, shared highest similarity in amino acids (35% identity) with the protein phosphatase methylesterase Ppel of S. cerevisiae. In haploid of S. cerevisiae, ectopic expressed CaPPE1 could partially suppress the invasive growth defect of the flo8 mutant but failed to suppressed the invasive growth defects of the mutants in MAPK pathway(ste12/ste12 and tec1/ tecl). Ectopic expression of the CaPPE1 in diploid of S. cerevisiae suppress the filamentous growth defect of some mutants in MAPK pathway, but not in flo8/flo8 mutant under nitrogen starvation condition. It is suggested that CaPpe1 may be involved in different regulating pathways in diploid filamentous growth and in haploid invasive growth.
酵母和菌丝形态的二态性转变是白色念珠菌致病性的最重要决定因素之一。这种转变受多种信号转导途径调控。转录因子Flo8在酿酒酵母的形态发生中起重要作用。在本研究中，将白色念珠菌基因组DNA文库导入酿酒酵母flo8/flo8突变体中，并分离出能够抑制侵袭性生长缺陷的基因。分离出一个新基因并命名为CaPPE1（白色念珠菌PPE1基因）。CaPPE1编码一种361个氨基酸的蛋白质CaPpe1，与酿酒酵母的蛋白质磷酸酶甲酯酶Ppel在氨基酸水平上具有最高的相似性（35%的同一性）。在酿酒酵母单倍体中，异位表达CaPPE1可以部分抑制flo8突变体的侵袭性生长缺陷，但不能抑制MAPK途径（ste12/ste12和tec1/tec1）突变体的侵袭性生长缺陷。在氮饥饿条件下，CaPPE1在酿酒酵母二倍体中的异位表达可抑制MAPK途径中一些突变体的丝状生长缺陷，但不能抑制flo8/flo8突变体的丝状生长缺陷。这表明CaPpe1可能参与二倍体丝状生长和单倍体侵袭性生长的不同调控途径。
