The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, People's Republic of China.
The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, People's Republic of China.
J Biotechnol. 2017 Oct 10;259:228-234. doi: 10.1016/j.jbiotec.2017.06.1204. Epub 2017 Jul 6.
Shiraia bambusicola can produce a type of hypocrellin, which is applied in antibacterial, antitumoral, and antiviral areas. Studies on the hypocrellin pathway have not been confirmed due to the deficiency of suitable genetic methods. We constructed a clustered regularly interspaced short palindromic repeat sequences (CRISPR)/Cas9 system in Shiraia sp. SUPER-H168 and targeted a polyketide synthase (SbaPKS). No hypocrellin production was detected in the ΔSbaPKS mutant. Relative expression levels of SbaPKS and its adjacent genes were extremely down-regulated in the ΔSbaPKS mutant compared to those in the wild strain. Subsequent pathogenicity assays showed that deletion of SbaPKS attenuated virulence on bamboo leaves. In contrast, restored hypocrellin in a SbaPKS overexpression strain generated necrotic lesions on bamboo leaves. These results suggest that SbaPKS is involved in hypocrellin biosynthesis and hypocrellin has an essential role in the virulence of S. bambusicola on bamboo leaves. The CRISPR/Cas9 system in Shiraia sp. will open an avenue for decoding the hypocrellin pathway and genome editing of other filamentous fungi. Strategies that disrupt hypocrellin biosynthesis may reduce the detriment of S. bambusicola.
密纹羽竹荪能够产生一种原卟啉啉，这种物质应用于抗菌、抗肿瘤和抗病毒领域。由于缺乏合适的遗传方法，原卟啉啉途径的研究尚未得到证实。我们在密纹羽竹荪 SUPER-H168 中构建了一个成簇规律间隔短回文重复序列（CRISPR）/Cas9 系统，并靶向一个聚酮合酶（SbaPKS）。在 ΔSbaPKS 突变体中未检测到原卟啉啉的产生。与野生型菌株相比，ΔSbaPKS 突变体中 SbaPKS 及其相邻基因的相对表达水平极显著下调。随后的致病性测定表明，SbaPKS 的缺失削弱了其对竹叶的致病力。相比之下，在 SbaPKS 过表达菌株中恢复原卟啉啉会在竹叶上产生坏死斑。这些结果表明，SbaPKS 参与原卟啉啉生物合成，原卟啉啉在密纹羽竹荪对竹叶的毒力中起重要作用。密纹羽竹荪中的 CRISPR/Cas9 系统将为解码原卟啉啉途径和编辑其他丝状真菌基因组开辟道路。破坏原卟啉啉生物合成的策略可能会降低密纹羽竹荪的危害。
