The Botrytis cinerea phytotoxin botcinic acid requires two polyketide synthases for production and has a redundant role in virulence with botrydial
The Botrytis cinerea phytotoxin botcinic acid requires two polyketide synthases for production and has a redundant role in virulence with botrydial
复制标题
DOI：
10.1111/j.1364-3703.2010.00692.x
复制
发表时间：
2011-08-01
影响因子：
4.9
通讯作者：
Viaud, Muriel
中科院分区：
文献类型：
--
作者：
Dalmais, Berengere;Schumacher, Julia;Viaud, Muriel
灰霉病菌灰葡萄孢产生两种主要的植物毒素，倍半萜botrydial，其生物合成基因簇已被确定，和聚酮botcinic酸。我们已经确定了两个聚酮合酶（PKS）编码基因，BcPKS6和BcPKS9，在番茄叶片感染过程中上调。基因失活和几个独立的突变体的次级代谢产物谱的分析表明，BcPKS6和BcPKS9是肉毒酸生物合成的关键酶。我们发现BcPKS6和BcPKS9基因，分别命名为BcBOA6和BcBO9（代表B. cinerea肉毒酸生物合成）位于不同的基因组基因座，每个基因座与其他推定的肉毒酸生物合成基因相邻，命名为BcBOA1至BcBOA17。推定的BcBOA基因的直向同源物存在于密切相关的真菌核盘菌中，但簇组织在两个物种之间不保守。至于葡萄球菌生物合成基因，BcBOA基因的表达在体外和植物生长过程中由G α亚基BCG 1共同调节。肉毒酸产量的损失不影响对菜豆和番茄叶片的毒力。然而，不产生肉毒酸或葡萄糖苷的双突变体（bcpks6 Delta bcbot2 Delta）表现出明显降低的毒力。因此，在B的毒力中，葡萄球菌和肉毒酸的作用是多余的。灰蝶已经被证实。
The grey mould fungus Botrytis cinerea produces two major phytotoxins, the sesquiterpene botrydial, for which the biosynthesis gene cluster has been characterized previously, and the polyketide botcinic acid. We have identified two polyketide synthase (PKS) encoding genes, BcPKS6 and BcPKS9, that are up-regulated during tomato leaf infection. Gene inactivation and analysis of the secondary metabolite spectra of several independent mutants demonstrated that both BcPKS6 and BcPKS9 are key enzymes for botcinic acid biosynthesis. We showed that BcPKS6 and BcPKS9 genes, renamed BcBOA6 and BcBO9 (for B. cinerea botcinic acid biosynthesis), are located at different genomic loci, each being adjacent to other putative botcinic acid biosynthetic genes, named BcBOA1 to BcBOA17. Putative orthologues of BcBOA genes are present in the closely related fungus Sclerotinia sclerotiorum, but the cluster organization is not conserved between the two species. As for the botrydial biosynthesis genes, the expression of BcBOA genes is co-regulated by the G alpha subunit BCG1 during both in vitro and in planta growth. The loss of botcinic acid production does not affect virulence on bean and tomato leaves. However, double mutants that do not produce botcinic acid or botrydial (bcpks6 Delta bcbot2 Delta) exhibit markedly reduced virulence. Hence, a redundant role of botrydial and botcinic acid in the virulence of B. cinerea has been demonstrated.