Regulatory genes controlling fatty acid catabolism and peroxisomal functions in the filamentous fungus Aspergillus nidulans
Regulatory genes controlling fatty acid catabolism and peroxisomal functions in the filamentous fungus Aspergillus nidulans
复制标题
DOI：
10.1128/ec.5.5.794-805.2006
复制
发表时间：
2006-05-01
期刊：
影响因子：
--
通讯作者：
Davis, Meryl A.
中科院分区：
文献类型：
--
作者：
Hynes, Michael J.;Murray, Sandra L.;Davis, Meryl A.
脂肪酸的催化作用在许多真菌的生活方式中很重要，包括植物和动物病原体。这已经在构巢曲霉中进行了研究，构巢曲霉可以在乙酸盐和脂肪酸作为碳源上生长，导致乙酰辅酶A（CoA）的产生：乙酰辅酶A通过位于过氧化物酶体中的乙醛酸旁路代谢，从而实现异生。对乙酸利用特异性的酶以及乙醛酸旁路酶的乙酸诱导是通过Znz-Cys，双核簇活化剂FacB。然而，乙醛酸旁路的酶以及脂肪酸β-氧化和过氧化物酶体蛋白也可由脂肪酸诱导。我们有：分离的突变体不能在脂肪酸上生长。两个相应的基因，farA和farB，编码两个高度保守的家族的相关Zn-2-Cys（6）双核蛋白存在于丝状子囊菌，包括植物病原体。在白色念珠菌、汉逊德巴利酵母和解脂耶氏酵母中发现了单一直系同源物，但在阿舒囊菌、克鲁维酵母、酵母属谱系中没有发现。北方印迹分析表明，farA基因的缺失消除了短链和长链脂肪酸对许多基因的诱导，而farB基因的缺失消除了短链诱导。在编码乙醛酸旁路、β-氧化和过氧化物酶体功能的基因中，已经确定了每种蛋白质的相同核心6-bp体外结合位点。该序列在其它丝状子囊菌C. albicans、D. hansenii和Y.在解脂酵母中，而不是在酿酒酵母中的相应基因中。
The catabolism of fatty acids is important in the lifestyle of many fungi, including plant and animal pathogens. This has been investigated in Aspergillus nidulans, which can grow on acetate and fatty acids as sources of carbon, resulting in the production of acetyl coenzyme A (CoA): Acetyl-CoA is metabolized via the glyoxalate bypass, located in peroxisomes, enabling gluconeogenesis. Acetate induction of enzymes specific for acetate utilization as well as glyoxalate bypass enzymes is via the Znz-Cys, binuclear cluster activator FacB. However, enzymes of the glyoxalate bypass as well as fatty acid beta-oxidation and peroxisomal proteins are also inducible by fatty acids. We have :isolated mutants that cannot grow on fatty acids. Two of the corresponding genes, farA and farB, encode two highly conserved families of related Zn-2-Cys(6) binuclear proteins present in filamentous ascomycetes, including plant pathogens. A single ortholog is found in the yeasts Candida albicans, Debaryomyces hansenii, and Yarrowia lipolytica, but not in the Ashbya, Kluyveromyces, Saccharomyces lineage. Northern blot analysis has shown that deletion of the farA gene eliminates induction of a number of genes by both short- and long-chain fatty acids, while deletion of the farB gene eliminates short-chain induction. An identical core 6-bp in vitro binding site for each protein has been identified in genes encoding glyoxalate bypass, beta-oxidation, and peroxisomal functions. This sequence is overrepresented in the 5' region of genes predicted to be fatty acid induced in other filamentous ascomycetes, C. albicans, D. hansenii, and Y. lipolytica, but not in the corresponding genes in Saccharomyces cerevisiae.