Metabolic Regulation of Two pksCT Gene Transcripts in Monascus ruber Impacts Citrinin Biosynthesis
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Published:2023-12-07
Issue:12
Volume:9
Page:1174
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ISSN:2309-608X
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Container-title:Journal of Fungi
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language:en
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Short-container-title:JoF
Author:
He Yi12ORCID, Zhu Lisha12, Dong Xingxing1, Li Aoran2, Xu Suyin2, Wang Liling3, Shao Yanchun4
Affiliation:
1. National R&D Center for Se-Rich Agricultural Products Processing, Hubei Engineering Research Center for Deep Processing of Green Se-Rich Agricultural Products, School of Modern Industry for Selenium Science and Engineering, Wuhan Polytechnic University, Wuhan 430023, China 2. Key Laboratory for Deep Processing of Major Grain and Oil, Ministry of Education, Hubei Key Laboratory for Processing and Transformation of Agricultural Products, School of Food Science and Engineering, Wuhan Polytechnic University, Wuhan 430023, China 3. College of Food Science and Engineering, Tarim University, Alar 843300, China 4. College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
Abstract
Citrinin (CIT), a secondary metabolite produced by the filamentous fungi Monascus species, exhibits nephrotoxic, hepatotoxic, and carcinogenic effects in mammals, remarkably restricting the utilization of Monascus-derived products. CIT synthesis is mediated through the pksCT gene and modified by multiple genetic factors. Here, the regulatory effects of two pksCT transcripts, pksCTα, and pksCTβ, generated via pre-mRNA alternative splicing (AS), were investigated using hairpin RNA (ihpRNA) interference, and their impact on CIT biosynthesis and the underlying mechanisms were assessed through chemical biology and transcriptome analyses. The CIT yield in ihpRNA-pksCTα and ihpRNA-pksCT (α + β) transformants decreased from 7.2 μg/mL in the wild-type strain to 3.8 μg/mL and 0.08 μg/mL, respectively. Notably, several genes in the CIT biosynthetic gene cluster, specifically mrl3, mrl5, mrr1, and mrr5 in the ihpRNA-pksCT (α + β) transformant, were downregulated. Transcriptome results revealed that silencing pksCT has a great impact on carbohydrate metabolism, amino acid metabolism, lipid metabolism, and AS events. The key enzymes in the citrate cycle (TCA cycle) and glycolysis were significantly inhibited in the transformants, leading to a decrease in the production of biosynthetic precursors, such as acetyl-coenzyme-A (acetyl-coA) and malonyl-coenzyme-A (malonyl-coA). Furthermore, the reduction of CIT has a regulatory effect on lipid metabolism via redirecting acetyl-coA from CIT biosynthesis towards lipid biosynthesis. These findings offer insights into the mechanisms underlying CIT biosynthesis and AS in Monascus, thus providing a foundation for future research.
Funder
National Natural Science Foundation of China Outstanding Youth Program of Hubei Provincial Natural Science Foundation
Subject
Plant Science,Ecology, Evolution, Behavior and Systematics,Microbiology (medical)
Reference40 articles.
1. Orange, red, yellow: Biosynthesis of azaphilone pigments in Monascus fungi;Chen;Chem. Sci.,2017 2. Overexpression of monacolin K biosynthesis genes in the Monascus purpureus azaphilone polyketide pathway;Zhang;J. Agric. Food Chem.,2019 3. Long, P.C., Zhu, L.S., Lai, H.F., Xu, S.Y., Dong, X.X., Shao, Y.C., Wang, L.L., Cheng, S.Y., Liu, G., and He, J.R. (2023). Monascus red pigment liposomes: Microstructural characteristics, stability, and anticancer activity. Foods, 12. 4. Red yeast rice: A systematic review of the traditional uses, chemistry, pharmacology, and quality control of an important Chinese folk medicine;Zhu;Front. Pharmacol.,2019 5. Yoon, H.R., Ku, D., Han, S., Shin, S.C., Kim, H.W., and Kim, H.J. (2022). Safety evaluation of mycotoxin citrinin production from Monascus ruber through whole-genome sequencing and analytical evaluation. 3 Biotech, 12.
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