Vacher S, Cotton P, Fèvre M
Laboratoire de Biologie Cellulaire Fongique (bât Lwoff), UMR CNRS 5122, Microbiologie et Génétique, Université Claude Bernard-Lyon I, 10 rue Dubois, 69622 Villeurbanne Cedex, France.
Gene. 2003 May 22;310:113-21. doi: 10.1016/s0378-1119(03)00525-0.
In yeast, the SNF1 gene product is essential for the release of catabolic repression. We report the isolation and characterization of an SNF1 homologue from the necrotrophic pathogen Sclerotinia sclerotiorum. Ss snf1 encodes a 765-amino-acid protein in which the catalytic domain has an overall identity with the yeast proteins varying from 55 to 76% while the C-terminal half of Ss SNF1 has a weak homology of about 20% with the yeast sequences. Reverse transcription-polymerase chain reaction showed that its transcripts were weakly and constitutively expressed in planta and in vitro regardless of the nature of the carbon sources and of the presence or absence of glucose. Expression of Ss snf1 in yeast cells allowed the snf1 mutant cells to utilize sucrose, raffinose or glycerol for growth while expression of the Ss snf1 catalytic domain did not restore growth on raffinose or glycerol. Ss SNF1 is structurally homologous to Snf1p, suggesting that the interactions between the kinase and the accessory subunits to activate the enzymatic complex are conserved in fungi.
在酵母中，SNF1基因产物对于解除分解代谢阻遏至关重要。我们报道了从坏死营养型病原菌核盘菌中分离和鉴定出的一个SNF1同源物。Ss snf1编码一个765个氨基酸的蛋白质，其中催化结构域与酵母蛋白的整体一致性在55%至76%之间，而Ss SNF1的C端一半与酵母序列的同源性较弱，约为20%。逆转录-聚合酶链反应表明，无论碳源的性质以及葡萄糖的存在与否，其转录本在植物体内和体外均呈弱组成型表达。在酵母细胞中表达Ss snf1可使snf1突变细胞利用蔗糖、棉子糖或甘油进行生长，而Ss snf1催化结构域的表达并不能恢复在棉子糖或甘油上的生长。Ss SNF1在结构上与Snf1p同源，这表明激酶与辅助亚基之间激活酶复合物的相互作用在真菌中是保守的。
