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The gene expression and enzymatic activity of pinoresinol-lariciresinol reductase during wood formation in Taiwania cryptomerioides Hayata

  • Nien-Ting Chiang , Li-Ting Ma , Yi-Ru Lee , Nai-Wen Tsao , Chih-Kai Yang , Sheng-Yang Wang and Fang-Hua Chu EMAIL logo
Published/Copyright: August 14, 2018
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Abstract

Taiwania (Taiwania cryptomerioides Hayata) is an indigenous conifer species of Taiwan. Various secondary metabolites of Taiwania with diverse bioactivities have been identified, and lignans are especially abundant in the heartwood (hW). In the present study, the wood of this species was separated to cambium (Cam), sapwood (sW), transition zone (TZ) and hW and their transcriptomes were sequenced. Three pinoresinol-lariciresinol reductases (PLRs; designated TcPLR1, TcPLR2.2 and TcPLR3), which are responsible for lignan biosynthesis, were cloned and their expressions in wood tissues were detected. TcPLRs had higher expression levels in Cam and sW in RNA-seq and reverse transcriptase-polymerase chain reaction (RT-PCR) results. Liquid chromatography-mass spectrometry (LC-MS) analysis of the reaction products of TcPLRs revealed that TcPLR1 can reduce (+)-pinoresinol to lariciresinol, and both TcPLR2.2 and TcPLR3 could reduce (+)-pinoresinol to lariciresinol and secoisolariciresinol.

  1. Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  2. Research funding: Financial assistance from the Ministry of Science and Technology of Taiwan is gratefully acknowledged.

  3. Employment or leadership: None declared.

  4. Honorarium: None declared.

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Supplementary Material:

The online version of this article offers supplementary material (https://doi.org/10.1515/hf-2018-0026).


Received: 2018-02-07
Accepted: 2018-07-13
Published Online: 2018-08-14
Published in Print: 2019-02-25

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