Wang Xiaodi, Wei Jingyi, Tang Fufang, Chen Fusheng
State Key Laboratory of Agricultural Microbiology, College of Food Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China.
State Key Laboratory of Agricultural Microbiology, College of Food Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China; School of Life Science, Guizhou Normal University, Universities Town, Huaxi District, Guiyang, Guizhou 550025, China.
Int J Biol Macromol. 2025 Feb;288:138604. doi: 10.1016/j.ijbiomac.2024.138604. Epub 2024 Dec 9.
Blue light, as an important environmental factor, greatly affects the production of Monascus pigments (MPs) and citrinin in Monascus spp. In this study, the deletion, complementation, and overexpression mutants of MrcreD from Monascus ruber M7, which encodes an arrestin-like protein, were constructed and cultivated on PDA (Potato dextrose agar) medium to study the effects of blue light on MPs and citrinin production. The results revealed that blue light inhibited the formation of cleistothecia, conidia, and the production of MPs and citrinin in M. ruber M7. However, under blue light, in contrast to M. ruber M7, MrcreD-overexpressing strain displayed increased production of extracellular yellow pigments and intracellular orange pigments, whereas MrcreD-deleted strain showed enhanced production of intracellular yellow and orange pigments. Then, the extracellular citrinin production decreased in both mutants. The RT-qPCR results demonstrated that compared to M. ruber M7, overexpressing MrcreD increased the expression of genes involved in MPs biosynthesis, and decreased the genes involved in citrinin biosynthesis, while deleting MrcreD increased the expression of citrinin-relative genes. This is the first time that the functions of MrcreD gene in filamentous fungi have been researched under blue light, and it provides a strategy for exploring complex light-regulatory systems in filamentous fungi.
蓝光作为一种重要的环境因素，对红曲霉菌种中红曲色素（MPs）和桔霉素的产生有很大影响。在本研究中，构建了来自红曲霉菌M7的MrcreD（编码一种类抑制蛋白）的缺失、互补和过表达突变体，并在PDA（马铃薯葡萄糖琼脂）培养基上培养，以研究蓝光对MPs和桔霉素产生的影响。结果表明，蓝光抑制了红曲霉菌M7中闭囊壳、分生孢子的形成以及MPs和桔霉素的产生。然而，在蓝光下，与红曲霉菌M7相比，过表达MrcreD的菌株细胞外黄色色素和细胞内橙色色素的产量增加，而缺失MrcreD的菌株细胞内黄色和橙色色素的产量增加。然后，两个突变体的细胞外桔霉素产量均下降。RT-qPCR结果表明，与红曲霉菌M7相比，过表达MrcreD增加了参与MPs生物合成的基因表达，并降低了参与桔霉素生物合成的基因表达，而缺失MrcreD则增加了桔霉素相关基因的表达。这是首次在蓝光下研究丝状真菌中MrcreD基因的功能，为探索丝状真菌复杂的光调节系统提供了一种策略。
