Involvement of ZFR1 of Fusarium verticillioides in kernel colonization and the regulation of FST1, a putative sugar transporter gene required for fumonisin biosynthesis on maize kernels
Involvement of ZFR1 of Fusarium verticillioides in kernel colonization and the regulation of FST1, a putative sugar transporter gene required for fumonisin biosynthesis on maize kernels
复制标题
DOI：
10.1111/j.1364-3703.2007.00458.x
复制
发表时间：
2008-03-01
影响因子：
4.9
通讯作者：
Woloshuk, C. P.
中科院分区：
文献类型：
--
作者：
Bluhm, B. H. .;Kim, H.;Woloshuk, C. P.
伏马菌素包括一类由轮枝镰刀菌在玉米粒定殖期间产生的致癌真菌毒素。在以前的工作中，我们确定了ZFR 1，这是预测编码的锌（II）2Cys 6锌指转录因子伏马菌素B-1（FB 1）生产过程中所需的籽粒生长。在这项研究中，我们的特点是ZFR 1在玉米籽粒定殖和诱导FB 1生物合成的作用。ZFR 1缺失株（Delta zfr 1）在胚乳组织和各种其他碳源（包括葡萄糖和支链淀粉）上的生长比野生型少约2.5倍。然而，Delta zfr 1菌株显示出比野生型更高的α-淀粉酶活性和参与淀粉糖化的基因的表达，从而表明Delta zfr 1菌株的生长减少不是由于淀粉分解酶的抑制。在野生型菌株中，编码推定的糖转运蛋白的六个基因的表达显着大于胚乳组织上的胚芽组织，至少有三个的六个基因的表达受到负面影响的破坏ZFR 1。有趣的是，FST 1的破坏对生长、籽粒定殖或籽粒pH没有影响，但使玉米籽粒上的FB 1产量降低约82%。基于这些发现，我们假设ZFR 1通过调节参与碳水化合物感知或摄取的基因来控制FB 1的生物合成。
Fumonisins comprise a class of carcinogenic mycotoxins produced by Fusarium verticillioides during colonization of maize kernels. In previous work, we identified ZFR1, which is predicted to encode a Zn(II) 2Cys6 zinc finger transcription factor required for fumonisin B-1 (FB1) production during growth on kernels. In this study, we characterized the role of ZFR1 in colonizing maize kernels and inducing FB1 biosynthesis. The ZFR1 deletion strain (Delta zfr1) grew approximately 2.5-fold less than the wild-type on endosperm tissue and a variety of other carbon sources, including glucose and amylopectin. However, the Delta zfr1 strain displayed higher alpha-amylase activity and expression of genes involved in starch saccharification than the wild-type, thus indicating that the reduced growth of the Delta zfr1 strain was not due to inhibition of amylolytic enzymes. In the wild-type strain, expression of six genes encoding putative sugar transporters was significantly greater on endosperm tissue than on germ tissue, and expression of at least three of the six genes was negatively affected by disruption of ZFR1. Intriguingly, disruption of FST1 had no effect on growth, kernel colonization or kernel pH but decreased FB1 production by approximately 82% on maize kernels. Based on these findings, we hypothesize that ZFR1 controls FB1 biosynthesis by regulating genes involved in the perception or uptake of carbohydrates.