Abstract:
Botcinic acid is a phytotoxic polyketide involved in the virulence of the gray mold fungus Botrytis cinerea. Here, we aimed to investigate the specific regulation of the cluster of Bcboa genes that is responsible for its biosynthesis. Our analysis showed that this cluster is located in a subtelomeric genomic region containing alternating G + C/A + T-balanced regions, and A + T-rich regions made from transposable elements that underwent RIP (Repeat-Induced Point mutation). Genetic analyses demonstrated that BcBoa13, a putative Zn2Cys6 transcription factor, is a nuclear protein with a major positive regulatory role on the expression of other Bcboa1-to-Bcboa12 genes, and botcinic acid production. In conclusion, the structure and the regulation of the botcinic acid gene cluster show similar features with the cluster responsible for the biosynthesis of the other known phytotoxin produced by B. cinerea, i.e., the sesquiterpene botrydial. Both clusters contain a gene encoding a pathway-specific Zn2Cys6 positive regulator, and both are surrounded by relics of transposons which raise some questions about the role of these repeated elements in the evolution and regulation of the secondary metabolism gene clusters in Botrytis.
摘要:
Botcinicacid是一种植物毒性聚酮化合物,与灰霉病菌Botrytiscinerea的毒力有关。这里,我们旨在研究负责其生物合成的Bcboa基因簇的特定调控。我们的分析表明,该簇位于包含交替的GC/AT平衡区域的亚端粒基因组区域,和由经历RIP(重复诱导点突变)的转座因子制成的富含A+T的区域。遗传分析表明,BcBoa13,一种推定的Zn2Cys6转录因子,是一种核蛋白,对其他Bcboa1至Bcboa12基因的表达具有主要的正调节作用,和肉毒酸生产。总之,该结构和调节的植物毒素簇显示出类似的特征,该簇负责生物合成的其他已知的植物毒素产生的。即,倍半萜属植物。两个簇都包含编码通路特异性Zn2Cys6正调节因子的基因,两者都被转座子的遗迹所包围,这对这些重复元素在葡萄孢属次生代谢基因簇的进化和调节中的作用提出了一些疑问。