Zhang Shuwen, Xu Tingting, Ren Yongyu, Song Lianjun, Liu Zhao, Kang Xiangyang, Li Yun
State Key Laboratory of Tree Genetics and Breeding, Beijing Forestry University, Beijing, China.
National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China.
Front Plant Sci. 2023 Apr 3;14:1030298. doi: 10.3389/fpls.2023.1030298. eCollection 2023.
The transcription factor family is a large plant gene family, participating in plant growth and development, secondary metabolite synthesis, biotic and abiotic stresses responses, and hormone signaling. Eucommia ulmoides is a widely planted economic tree species in China that can produce trans-polyisoprene: Eucommia rubber (Eu-rubber). However, genome-wide identification of the NAC gene family has not been reported in . In this study, 71 NAC proteins were identified based on genomic database of . Phylogenetic analysis showed that the EuNAC proteins were distributed in 17 subgroups based on homology with NAC proteins in Arabidopsis, including the E. ulmoides-specific subgroup Eu_NAC. Gene structure analysis suggested that the number of exons varied from 1 to 7, and multitudinous genes contained two or three exons. Chromosomal location analysis revealed that the genes were unevenly distributed on 16 chromosomes. Three pairs of genes of tandem duplicates genes and 12 segmental duplications were detected, which indicated that segmental duplications may provide the primary driving force of expansion of . Prediction of cis-regulatory elements indicated that the genes were involved in development, light response, stress response and hormone response. For the gene expression analysis, the expression levels of genes in various tissues were quite different. To explore the effect of genes on Eu-rubber biosynthesis, a co-expression regulatory network between Eu-rubber biosynthesis genes and genes was constructed, which indicated that six genes may play an important role in the regulation of Eu-rubber biosynthesis. In addition, this six genes expression profiles in E. ulmoides different tissues were consistent with the trend in Eu-rubber content. Quantitative real-time PCR analysis showed that genes were responsive to different hormone treatment. These results will provide a useful reference for further studies addressing the functional characteristics of the NAC genes and its potential role in Eu-rubber biosynthesis.
转录因子家族是一个庞大的植物基因家族，参与植物生长发育、次生代谢物合成、生物和非生物胁迫响应以及激素信号传导。杜仲是中国广泛种植的经济树种，能够产生反式聚异戊二烯，即杜仲橡胶（Eu-橡胶）。然而，尚未见关于杜仲NAC基因家族全基因组鉴定的报道。在本研究中，基于杜仲基因组数据库鉴定出71个NAC蛋白。系统发育分析表明，根据与拟南芥中NAC蛋白的同源性，杜仲NAC蛋白分布在17个亚组中，包括杜仲特有的亚组Eu_NAC。基因结构分析表明，外显子数量从1到7不等，许多基因含有两个或三个外显子。染色体定位分析显示，这些基因在16条染色体上分布不均。检测到三对串联重复基因和12个片段重复，这表明片段重复可能是杜仲NAC基因家族扩张的主要驱动力。顺式调控元件预测表明，这些基因参与发育、光响应、胁迫响应和激素响应。对于基因表达分析，各组织中这些基因的表达水平差异很大。为了探究这些基因对杜仲橡胶生物合成的影响，构建了杜仲橡胶生物合成基因与这些基因之间的共表达调控网络，这表明六个杜仲NAC基因可能在杜仲橡胶生物合成调控中发挥重要作用。此外，这六个杜仲NAC基因在杜仲不同组织中的表达谱与杜仲橡胶含量的变化趋势一致。定量实时PCR分析表明，这些基因对不同激素处理有响应。这些结果将为进一步研究杜仲NAC基因的功能特性及其在杜仲橡胶生物合成中的潜在作用提供有用的参考。
