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Functional characterization of a WRKY family gene involved in somatic embryogenesis in Panax ginseng

  • Yu Yang
  • Ni Wang
  • Shoujing ZhaoEmail author
Original Article


As a perennial herbaceous species, Panax ginseng is widely cultivated and used as traditional herbal medicine. The root of Panax ginseng commonly remains expensive as conventional breeding of Panax ginseng is difficult. Somatic embryogenesis (S.E.) is a useful tool for plant propagation and optimal model for understanding the mechanisms of plant embryogenesis. In Panax ginseng, increasing studies have been widely performed to optimize the technology of S.E., while the underlying mechanism remains unclear. In this paper, we cloned and identified a WRKY family gene named PgWRKY6 which is upregulated in response to 2,4-D (2,4-dichlorophenoxyacetic acid)-induced embryogenic callus development. The silencing of PgWRKY6 obviously reduces the induction rate of embryogenic callus, indicating its crucial role in S.E. of Panax ginseng hairy root. The expressions of several ROS-scavenging genes are also inducible during embryogenic callus development, and the transcriptions of PgGST, PgAPX1, and PgSOD are demonstrated to be regulated by PgWRKY6. Recombinant PgWRKY6, an approximate 40-KDa protein purified from Escherichia coli, shows a specific DNA-binding activity with a potential recognition site of TTGAC(C/T). This work demonstrated that as a conserved WRKY family transcription factor, PgWRKY6 functions upstream of PgGST, PgAPX1, and PgSOD, and potentially mediated auxins –ROS signaling pathway in the process of S.E. in Panax species.


Panax ginseng PgWRKY6 ROS-scavenging l Somatic embryogenesis 


Authors’ contribution

Designed research: S.Z., Y.Y; performed research: Y.Y.; analyzed data: N.W; WROTE the paper: Y.Y.

Funding information

This work is supported by the National Natural Science Foundation of China (31270337 to S.Z.), Science and Technology Development Program of Jilin province (20190201157JC to S.Z.), and Supporting Fund for Teachers’ Research of Jining Medical University to Y.Y. (JYFC2018JS009).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

709_2019_1455_MOESM1_ESM.pdf (299 kb)
ESM 1 (PDF 298 kb)


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Copyright information

© Springer-Verlag GmbH Austria, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Shandong Collaborative Innovation Center for Diagnosis, Treatment and Behavioral InterventionsJining Medical UniversityJiningChina
  2. 2.School of Life SciencesJilin UniversityChangchunChina
  3. 3.Changchun Vocational Institute of TechnologyChangchunChina

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