High Chromosomal Stability and Immortalized Totipotency Characterize Long-Term Tissue Cultures of Chinese Ginseng (Panax Ginseng).

Sitong Liu,Yutong Liu,Xinfeng Wang,Zhenhui Wang,Lili Jiang,Xiaodong Liu,Linfeng Li,Ning Li,Bao Liu,Xueqi Fu,Jing Zhao,Xiaomeng Li

doi:10.3390/genes12040514

Abstract

Chinese ginseng (Panax ginseng C. A. Meyer) is a highly cherished traditional Chinese medicine, with several confirmed medical effects and many more asserted health-boosting functions. Somatic chromosomal instability (CIN) is a hallmark of many types of human cancers and also related to other pathogenic conditions such as miscarriages and intellectual disabilities, hence, the study of this phenomenon is of wide scientific and translational medical significance. CIN also ubiquitously occurs in cultured plant cells, and is implicated as a major cause of the rapid decline/loss of totipotency with culture duration, which represents a major hindrance to the application of transgenic technologies in crop improvement. Here, we report two salient features of long-term cultured callus cells of ginseng, i.e., high chromosomal stability and virtually immortalized totipotency. Specifically, we document that our callus of ginseng, which has been subcultured for 12 consecutive years, remained highly stable at the chromosomal level and showed little decline in totipotency. We show that these remarkable features of cultured ginseng cells are likely relevant to the robust homeostasis of the transcriptional expression of specific genes (i.e., genes related to tissue totipotency and chromosomal stability) implicated in the manifestation of these two complex phenotypes. To our knowledge, these two properties of ginseng have not been observed in any animals (with respect to somatic chromosomal stability) and other plants. We posit that further exploration of the molecular mechanisms underlying these unique properties of ginseng, especially somatic chromosomal stability in protracted culture duration, may provide novel clues to the mechanistic understanding of the occurrence of CIN in human disease.

Highlights

We propose that further elucidation of the molecular mechanisms underlying these properties of ginseng, especially somatic chromosomal stability, is scientifically intriguing and may bear important implications for human health with respect to the occurrence of chromosome instability (CIN) in many human pathogenic conditions
The embryogenic state of the ginseng callus remained unaltered over 12 years of continuous subculture and showed a high frequency (>95%) of plantlet regeneration, defined as totipotency
We report two striking biological properties characterizing long-term callus cultures of Chinese ginseng: high chromosomal stability and virtually immortalized totipotency

Summary

Introduction

A given combination of chromosome number and structure constitutes a distinct chromosomal complement, i.e., karyotype, which characterizes every eukaryotic organism, and is usually very stable. It is known that the karyotype undergoes dramatic changes under intrinsic or environmental stresses, some of which can be mitotically and/or meiotically heritable. Changes in karyotype can be of major evolutionary significance, such as speciation [1,2]. Abnormal deviations of the chromosome number and structure in somatic cells of the human body, collectively termed 4.0/). Chromosome instability (CIN), may have catastrophic consequences and are often causally linked to severe pathogenic conditions, especially many types of cancer [3,4,5,6,7]. Understanding the factors influencing, and mechanisms underpinning, somatic

Results

Discussion

Conclusion