Dynamic evolution of Panax species

Abstract

Background: Panax ginseng is one of the most valuable medicinal plants in Korea. However, deciphering its full genome sequence information for crop improvement has been hampered due to its complex genomic, genetic, and growth characteristics. Many efforts have been made in the past decade to overcome these limitations and understand the genome structure and the evolutionary history of P. ginseng.

Methods: This review aims to discuss the current status of genomic studies on P. ginseng and related species, and the experimental clues suggesting phylogenetic classification and evolutionary history of the genus Panax.

Conclusion: The development of sequencing technologies made genome sequencing of the large P. ginseng genome possible, providing fundamental information to deciphering the evolutionary history of P. ginseng and related species. P. ginseng went through two rounds of whole genome duplication events after diverging from the closest family Apiaceae, which was unveiled from complete whole genome sequences. Further in-depth comparative genome analysis with other related species and genera will uncover the evolutionary history as well as important morphological and ecological characteristics of Panax species.

Keywords: Evolution; Panax ginseng; Whole genome duplication; Whole genome sequence.

Fig. 1

Simultaneous detection of repeat elements in P. ginseng chromosomes using multi-color FISH. FISH signals are shown for transposable element (a, b), and satellite DNA (c, d) probes. a PgDel1-Cy5, b PgDel2-DEAC, c Pg167TRa-Texas Red, and d Pg167TRb-Alexa Fluor 488. e Chromosomes from a–d were arranged according to PgDel2 signal and chromosome length. The last row in e show the merged signals of the four repeats. Bars = 10 µm (color figure online)

Fig. 2

Two whole genome duplication events occurring for Panax species. Reorganized and redrawn based on divergence time estimations of Lee et al. (2017), Kim et al. (2017), and Kim et al. (2018)

Fig. 3

Distribution of PgDel2 retrotransposon in diploid P. notoginseng and tetraploid P. ginseng and P. quinquefolius. In P. notoginseng, PgDel2 was dispersed in pericentromeric regions of all chromosomes. In tetraploid Panax, PgDel2 was concentrated at pericentromeric regions in 24 out of 48 chromosomes. Bar = 10 µm

Fig. 4

Two intercontinental migration of Panax species recreated based on Kim et al. (2018). P. g P. ginseng, P. s P. stipuleanatus, P. j P. japonicas, P. v P. vietnamensis, P. n P. notoginseng, P. t P. trifolius, P. q P. quinquefolius