Riboflavin Accumulation and Molecular Characterization of cDNAs Encoding Bifunctional GTP Cyclohydrolase II/3,4-Dihydroxy-2-Butanone 4-Phosphate Synthase, Lumazine Synthase, and Riboflavin Synthase in Different Organs of Lycium chinense Plant

Molecules

Pham Anh Tuan¹  Shicheng Zhao¹  Jae Kwang Kim⁵  Yeon Bok Kim¹  Jingli Yang⁴  Cheng Hao Li⁴  Sun-Ju Kim²  Mariadhas Valan Arasu³  Naif Abdullah Al-Dhabi³  Sang Un Park¹ 

[1] Department of Crop Science, Chungnam National University, 99 Daehak-Ro, Yuseong-gu, Daejeon 305-764, Korea; E-Mails:;Department of Bio-Environmental Chemistry, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 305-764, Korea; E-Mail:;Department of Botany and Microbiology, Addiriyah Chair for Environmental Studies, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia; E-Mail:;State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China; E-Mails:;Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 406-772, Korea; E-Mail:

关键词: GTP cyclohydrolase II/3;    4-dihydroxy-2-butanone-4-phosphate synthase;    lumazine synthase;    riboflavin synthase;    Lycium chinense;    riboflavin;   

DOI  :  10.3390/molecules191117141

来源: mdpi

【 摘 要 】

Riboflavin (vitamin B2) is the precursor of flavin mononucleotide and flavin adenine dinucleotide—essential cofactors for a wide variety of enzymes involving in numerous metabolic processes. In this study, a partial-length cDNA encoding bifunctional GTP cyclohydrolase II/3,4-dihydroxy-2-butanone-4-phosphate synthase (LcRIBA), 2 full-length cDNAs encoding lumazine synthase (LcLS1 and LcLS2), and a full-length cDNA encoding riboflavin synthase (LcRS) were isolated from Lycium chinense, an important traditional medicinal plant. Sequence analyses showed that these genes exhibited high identities with their orthologous genes as well as having the same common features related to plant riboflavin biosynthetic genes. LcRIBA, like other plant RIBAs, contained a DHBPS region in its N terminus and a GCHII region in its C-terminal part. LcLSs and LcRS carried an N-terminal extension found in plant riboflavin biosynthetic genes unlike the orthologous microbial genes. Quantitative real-time polymerase chain reaction analysis showed that 4 riboflavin biosynthetic genes were constitutively expressed in all organs examined of L. chinense plants with the highest expression levels found in the leaves or red fruits. LcRIBA, which catalyzes 2 initial reactions in riboflavin biosynthetic pathway, was the highest transcript in the leaves, and hence, the richest content of riboflavin was detected in this organ. Our study might provide the basis for investigating the contribution of riboflavin in diverse biological activities of L. chinense and may facilitate the metabolic engineering of vitamin B2 in crop plants.

【 授权许可】

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