College of Life Science, Jilin Agricultural University, Changchun, Jilin, China.
Research Center for Ginseng Genetic Resources Development and Utilization, Changchun, Jilin, China.
PLoS One. 2020 Jun 11;15(6):e0234423. doi: 10.1371/journal.pone.0234423. eCollection 2020.
The NAC gene family is one of the important plant-specific transcription factor families involved in variety of physiological processes. It has been found in several plant species; however, little is known about the gene family in ginseng, Panax ginseng C.A. Meyer. Here we report identification and systematic analysis of this gene family in ginseng. A total of 89 NAC genes, designated PgNAC01 to PgNAC89, are identified. These genes are alternatively spliced into 251 transcripts at fruiting stage of a four-year-old ginseng plant. The genes of this gene family have five conserved motifs and are clustered into 11 subfamilies, all of which are shared with the genes of the NAC gene families identified in the dicot and monocot model plant species, Arabidopsis and rice. This result indicates that the PgNAC gene family is an ancient and evolutionarily inactive gene family. Gene ontology (GO) analysis shows that the functions of the PgNAC gene family have been substantially differentiated; nevertheless, over 86% the PgNAC transcripts remain functionally correlated. Finally, five of the PgNAC genes, PgNAC05-2, PgNAC41-2, PgNAC48, PgNAC56-1, and PgNAC59, are identified to be involved in plant response to cold stress, suggesting that this gene family plays roles in response to cold stress in ginseng. These results, therefore, provide new insights into functional differentiation and evolution of a gene family in plants and gene resources necessary to comprehensively determine the functions of the PgNAC gene family in response to cold and other abiotic stresses in ginseng.
NAC 基因家族是参与多种生理过程的植物特异性转录因子家族之一。它已在几种植物物种中被发现；然而，关于人参 Panax ginseng C.A. Meyer 中的基因家族，人们知之甚少。在这里，我们报告了在人参中鉴定和系统分析这个基因家族的情况。总共鉴定到 89 个 NAC 基因，命名为 PgNAC01 到 PgNAC89。这些基因在 4 年生人参果实期被剪接为 251 个转录本。该基因家族的基因具有 5 个保守基序，并聚类为 11 个亚家族，所有这些亚家族都与拟南芥和水稻等双子叶和单子叶模式植物中鉴定的 NAC 基因家族的基因共享。这一结果表明，PgNAC 基因家族是一个古老且进化上不活跃的基因家族。基因本体论（GO）分析表明，PgNAC 基因家族的功能已经发生了实质性的分化；然而，超过 86%的 PgNAC 转录本仍然具有功能相关性。最后，鉴定到 5 个 PgNAC 基因，即 PgNAC05-2、PgNAC41-2、PgNAC48、PgNAC56-1 和 PgNAC59，参与植物对冷胁迫的响应，表明该基因家族在人参对冷胁迫的响应中发挥作用。因此，这些结果为植物中一个基因家族的功能分化和进化以及确定 PgNAC 基因家族在人参对冷胁迫和其他非生物胁迫响应中的功能所需的基因资源提供了新的见解。
