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A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products
Published on: October 4, 2019
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Two Cycloartenol Synthases for Phytosterol Biosynthesis in Polygala tenuifolia Willd
Mei Lan Jin1, Woo Moon Lee2, Ok Tae Kim3
1Department of Herbal Crop Research, National Institute of Horticultural and Herbal Science, Rural Development Administration, Eumseong 27709, Korea. milan80623@korea.kr.
International Journal of Molecular Sciences
|November 16, 2017
Summary
This study identifies two novel oxidosqualene cyclase (OSC) genes, PtCAS1 and PtCAS2, in Polygala tenuifolia. Methyl jasmonate treatment significantly increased the expression of these genes, suggesting their role in triterpenoid biosynthesis.
Area of Science:
- Biochemistry
- Molecular Biology
- Plant Science
Background:
- Oxidosqualene cyclases (OSCs) are crucial enzymes regulating phytosterol and triterpene saponin biosynthesis.
- Understanding OSC gene function is vital for elucidating plant metabolic pathways.
Purpose of the Study:
- To identify and characterize novel OSC genes in *Polygala tenuifolia* seedlings.
- To investigate the effect of methyl jasmonate (MeJA) on the expression of these OSC genes.
Main Methods:
- RNA-sequencing (RNA-Seq) analysis was performed on *Polygala tenuifolia* seedlings under control and MeJA-treated conditions.
- Differential gene expression was analyzed using fragments per kilobase million (FPKM) values.
- Putative OSC genes were isolated, characterized in yeast cells, and their expression patterns were analyzed using quantitative real-time PCR (qRT-PCR).
Main Results:
- Two full-length cDNAs of putative OSC genes, *PtCAS1* and *PtCAS2*, were identified.
- Functional expression in yeast confirmed that *PtCAS1* and *PtCAS2* produce cycloartenol.
- Gene expression was highest in flowers (*PtCAS1*) and roots (*PtCAS2*).
- MeJA treatment led to a 1.5-fold increase in *PtCAS1* and a 2-fold increase in *PtCAS2* transcripts.
Conclusions:
- The identified *PtCAS1* and *PtCAS2* genes encode functional cycloartenol synthases in *Polygala tenuifolia*.
- MeJA significantly induces the expression of *PtCAS1* and *PtCAS2*, highlighting their role in MeJA-responsive triterpenoid biosynthesis.
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