Wang Fen, Song Xinhua, Dong Xiaoming, Zhang Jiaojiao, Dong Caihong
State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, No. 3 1st Beichen West Road, Beijing, Chaoyang District, 100101, China.
School of Life Sciences, Shandong University of Technology, Zibo, Shandong, 255000, China.
Appl Microbiol Biotechnol. 2017 Jun;101(11):4645-4657. doi: 10.1007/s00253-017-8276-7. Epub 2017 Apr 13.
Cryptochromes (CRYs) belong to the photolyase/cryptochrome flavoprotein family, which is widely distributed in all kingdoms. A phylogenetic analysis indicated that three Cordyceps militaris proteins [i.e., cryptochrome DASH (CmCRY-DASH), (6-4) photolyase, and cyclobutane pyrimidine dimer (CPD) class I photolyase] belong to separate fungal photolyase/cryptochrome subfamilies. CmCRY-DASH consists of DNA photolyase and flavin adenine dinucleotide-binding domains, with RGG repeats in a C-terminal extension. Considerably, more carotenoids and cordycepin accumulated in the ΔCmcry-DASH strain than in the wild-type or ΔCmwc-1 strains, indicating an inhibitory role for CmCRY-DASH in these biosynthetic pathways. Fruiting body primordia could form in the ΔCmcry-DASH strain, but the fruiting bodies were unable to elongate normally, differently from the Cmwc-1 disruption strain, where primordium differentiation did not occur. Cmcry-DASH expression is induced by light in the wild-type strain, but not in the ΔCmwc-1 strain. CmCRY-DASH is also necessary for the expression of Cmwc-1, implying that Cmcry-DASH and Cmwc-1 exhibit interdependent expression. The Cmvvd expression levels in the wild-type and ΔCmcry-DASH strains increased considerably following irradiation, while Cmvvd expression in the ΔCmwc-1 strain was not induced by light. It is speculated that the photo adaptation may be faster in the Cmcry-DASH mutant based on Cmvvd transcript dynamics. These results provide new insights into the biological functions of fungal DASH CRYs. Furthermore, the DASH CRYs may regulate fruiting body development and secondary metabolism differently than WC-1.
隐花色素（CRYs）属于光解酶/隐花色素黄素蛋白家族，广泛分布于所有生物界。系统发育分析表明，三种蛹虫草蛋白[即隐花色素DASH（CmCRY-DASH）、（6-4）光解酶和环丁烷嘧啶二聚体（CPD）I类光解酶]属于不同的真菌光解酶/隐花色素亚家族。CmCRY-DASH由DNA光解酶和黄素腺嘌呤二核苷酸结合结构域组成，在C末端延伸区有RGG重复序列。值得注意的是，与野生型或ΔCmwc-1菌株相比，ΔCmcry-DASH菌株中积累了更多的类胡萝卜素和虫草素，这表明CmCRY-DASH在这些生物合成途径中起抑制作用。ΔCmcry-DASH菌株中可形成子实体原基，但子实体不能正常伸长，这与不发生原基分化的ΔCmwc-1缺失菌株不同。在野生型菌株中，CmCRY-DASH的表达受光诱导，但在ΔCmwc-1菌株中不受光诱导。CmCRY-DASH对Cmwc-1的表达也是必需的，这意味着Cmcry-DASH和Cmwc-1表现出相互依赖的表达。照射后，野生型和ΔCmcry-DASH菌株中的Cmvvd表达水平显著增加，而ΔCmwc-1菌株中的Cmvvd表达不受光诱导。根据Cmvvd转录本动态推测，Cmcry-DASH突变体中的光适应可能更快。这些结果为真菌DASH CRYs的生物学功能提供了新的见解。此外，DASH CRYs可能与WC-1不同地调节子实体发育和次生代谢。
