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Plant function and evolutionary biology
RESEARCH ARTICLE

iTRAQ and RNA-seq analyses provide an insight into mechanisms of recalcitrance in a medicinal plant Panax notoginseng seeds during the after-ripening process

Na Ge A B C , Kai Yang A B C , Ling Yang A B C , Zhen-Gui Meng A B C , Long-Geng Li A B C and Jun-Wen Chen https://orcid.org/0000-0003-3902-1784 A B C *
+ Author Affiliations
- Author Affiliations

A College of Agronomy and Biotechnology, Yunnan Agricultural University, Fengyuan Road, Panlong District, Kunming, Yunnan 650201, China.

B The Key Laboratory of Medicinal Plant Biology of Yunnan Province, Yunnan Agricultural University, Fengyuan Road, Panlong District, Kunming, Yunnan 650201, China.

C National and Local Joint Engineering Research Center on Germplasm Innovation and Utilization of Chinese Medicinal Materials in Southwestern China, Yunnan Agricultural University, Fengyuan Road, Panlong District, Kunming, Yunnan 650201, China.

* Correspondence to: cjw31412@hotmail.com

Handling Editor: Thomas Roberts

Functional Plant Biology 49(1) 68-88 https://doi.org/10.1071/FP21197
Submitted: 29 October 2020  Accepted: 20 October 2021   Published: 26 November 2021

© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing

Abstract

Panax notoginseng (Burk) F.H. Chen is an important economic and medicinal plant from the family of Araliaceae, and its seed is characterised by the recalcitrance and after-ripening process. However, the molecular mechanism on the dehydration sensitivity is not clear in recalcitrant seeds. In the present study, isobaric tag for relative and absolute quantification (iTRAQ) and RNA-seq were used to analyse the proteomic and transcriptomic changes in seeds of P. notoginseng in days after-ripening (DAR). A total of 454 differentially expressed proteins (DEPs) and 12 000 differentially expressed genes (DEGs) were obtained. The activity of enzymes related to antioxidant system were significantly increased, and the late embryogenesis abundant (LEA) protein family and most members of glutathione metabolism enzymes have been downregulated during the after-ripening process. The lack or inadequate accumulation of LEA proteins in the embryo and the low activity of antioxidant defense in glutathione metabolism might be the key factors leading to the dehydration sensitivity in recalcitrant seeds of P. notoginseng. In addition, the increased activity of elycolysis (EMP), citric acid cycle (TCA) and pentose phosphate pathway (PPP) pathways might be one of important signals to complete the after-ripening process. Overall, our study might provide a new insight into the molecular mechanism on dehydration sensitivity of recalcitrant seeds.

Keywords: after-ripening process, dehydration sensitivity, iTRAQ, Panax notoginseng, proteomics, recalcitrant seeds, RNA-seq, transcriptome.


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