title: Evolutionary origin of the NCSI gene subfamily encoding norcoclaurine synthase is associated with the biosynthesis of benzylisoquinoline alkaloids in plants.
abstract: Sacred lotus is rich in biologically active compounds, particularly benzylisoquinoline alkaloids (BIAs). Here, we report on isolation of genes encoding (S)-norcoclaurine synthase (NCS) in sacred lotus, which is a key entry-enzyme in BIA biosynthesis. Seven NCS genes, designated NnNCS1 through NnNCS7, were identified in the sacred lotus genome, and five are located next to each other within a 83 kb region on scaffold 8. The NCS genes are divided into two subfamilies, designated NCSI and NCSII. The NCSII genes are universal in plants, while the NCSI genes are only identified in a limited number of dicotyledonous taxa that produce BIAs. In sacred lotus, only NnNCS4 belongs to the NCSII subfamily, whilst the rest NCS genes within the NCSI subfamily. Overall, the NnNCS7 gene was predominantly expressed in all tested tissues, and its expression is significantly correlated with alkaloid content in leaf. In contrast, the NnNCS4 expression shows no significant correlation with alkaloid accumulation in leaf, and its lack of expression cannot inhibit alkaloid accumulation. Taken together, these results suggest that the NCSI subfamily is crucial for BIA biosynthesis, and its origin may represent an important evolutionary event that allows certain plant taxa to produce BIAs.
authors.affiliation: Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden of the Chinese Academy of Sciences, Wuhan, 430074, P. R. China.|Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Sornkanok
authors.initials: S
authors.lastname: Vimolmangkang
authors.affiliation: Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden of the Chinese Academy of Sciences, Wuhan, 430074, P. R. China.
authors.forename: Xianbao
authors.initials: X
authors.lastname: Deng
authors.affiliation: Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden of the Chinese Academy of Sciences, Wuhan, 430074, P. R. China.|Graduate University of Chinese Academy of Sciences, 19A Yuquanlu, Beijing, 100049, China.
authors.forename: Albert
authors.initials: A
authors.lastname: Owiti
authors.affiliation: Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Thitirat
authors.initials: T
authors.lastname: Meelaph
authors.affiliation: Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden of the Chinese Academy of Sciences, Wuhan, 430074, P. R. China.|Graduate University of Chinese Academy of Sciences, 19A Yuquanlu, Beijing, 100049, China.
authors.forename: Collins
authors.initials: C
authors.lastname: Ogutu
authors.affiliation: Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden of the Chinese Academy of Sciences, Wuhan, 430074, P. R. China.|Sino-African Joint Research Center, Chinese Academy of Sciences, Wuhan, 430074, China.
authors.forename: Yuepeng
authors.initials: Y
authors.lastname: Han
mesh_terms: D000470:Alkaloids / Q000096:biosynthesis*; D044182:Benzylisoquinolines / Q000378:metabolism*; D005075:Biological Evolution; D019731:Carbon-Nitrogen Ligases / Q000235:genetics*; D031653:Nelumbo / Q000201:enzymology* / Q000235:genetics*; D018515:Plant Leaves / Q000201:enzymology
chemical_list: D000470:Alkaloids; D044182:Benzylisoquinolines; D019731:Carbon-Nitrogen Ligases; C450500:norcoclaurine synthase