Transcriptome analysis associated with polysaccharide synthesis and their antioxidant activity in Cyclocarya paliurus leaves of different developmental stages

Weida Lin; Huanwei Chen; Jianmei Wang; Yongli Zheng; Qiuwei Lu; Ziping Zhu; Na Li; Zexin Jin; Junmin Li; Hongfei Lu

doi:10.7717/peerj.11615

Transcriptome analysis associated with polysaccharide synthesis and their antioxidant activity in Cyclocarya paliurus leaves of different developmental stages

PeerJ. 2021 Jun 14:9:e11615. doi: 10.7717/peerj.11615. eCollection 2021.

Authors

Weida Lin^{1

2}, Huanwei Chen³, Jianmei Wang⁴, Yongli Zheng⁵, Qiuwei Lu¹, Ziping Zhu¹, Na Li¹, Zexin Jin¹, Junmin Li¹, Hongfei Lu²

Affiliations

¹ Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation, Taizhou University, Taizhou, ZheJiang, China.
² College of Life Science and Medicine, Zhejiang Sci-Tech University, Hangzhou, Zhejiang, China.
³ Forest Research Institute of Longquan City, Longquan, Zhejiang, China.
⁴ Zhejiang Yuanyang Agriculture Development Co. Ltd, Suichang, Zhejiang, China.
⁵ Zhejiang Provincial Agricultural Products Quality Safety Center, Hangzhou, Zhejiang, China.

Abstract

Background: Cyclocarya paliurus (Batal.) Iljinskaja is a common endemic tree species and used as a Chinese medicine. The main active components in the leaves of this plant are polysaccharides. However, the temporal patterns of gene expression underlying the synthesis of polysaccharides in C. paliurus at different leaf developmental stages and its relationship with the polysaccharide content and antioxidant activities has not been reported to date.

Methods: RNA-seq was used to investigate the biosynthesis pathway of polysaccharides at the four developmental stages of C. paliurus leaves. The content and the antioxidant activities of polysaccharides were measured with typical biochemical methods and the identified correlations were statistically evaluated.

Results: Sixty-nine differentially expressed genes were found in the leaves during different developmental stages of C. paliurus. These are associated with glycosyltransferases and belong to 18 families. During different developmental stages of C. paliurus, the polysaccharide content first increased and then decreased, and the UDP-glucose 4-epimerase gene was found to be significantly positively correlated with the polysaccharide content. The clearance rates of DPPH radicals, superoxide anion radicals, hydroxyl radicals, and the reducing power of polysaccharides in the leaves of C. paliurus at different developmental stages showed a dose-dependent relationship with the concentration of polysaccharides.

Conclusions: The smallest fully expanded leaves are suitable for high-quality tea, and leaves with sizes below the largest fully expanded leaves are suitable for industrial production of polysaccharides.

Keywords: Antioxidant activity; Cyclocarya paliurus; Industrial production; Polysaccharide biosynthesis.

Grants and funding

This work was financially supported by Zhejiang Provincial Key Research and Development Program (2018C02021) and the Ten Thousand Talent Program of Zhejiang Province (2019R52043). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.