园艺学报 ›› 2019, Vol. 46 ›› Issue (7): 1303-1319.doi: 10.16420/j.issn.0513-353x.2018-0717

• 研究论文 • 上一篇    下一篇



  1. 1南京农业大学园艺学院,南京 210095;2江苏省农业科学院种质资源与生物技术研究所,南京 210014
  • 出版日期:2019-07-25 发布日期:2019-07-25
  • 基金资助:

Identification and Expression Analysis of NAC Transcription Factor Gene Family Under Low Temperature in Cucumis sativus var. hardwickii

ZHAO Yanqing1,DU Jianchang2,WANG Panqiao1,QIN Xiaodong1,and CHEN Jinfeng1,*   

  1. 1College of Horticulture,Nanjing Agricultural University,Nanjing 210095,China;2Institute of Crop Germplasm and Biotechnology,Jiangsu Academy of Agricultural Science,Nanjing 210014,China
  • Online:2019-07-25 Published:2019-07-25

摘要: 以哈氏黄瓜(Cucumis sativus var. hardwickii)为试验材料,基于全基因组测序结果,利用生物信息学分析方法,鉴定获得77个NAC转录因子,其结构高度保守,序列长度在151 ~ 653个氨基酸之间,在7条染色体中呈非均匀分布;理论等电点在4.54 ~ 9.10之间;大部分转录因子定位在细胞核和细胞质膜上;系统发生分析显示所有NAC转录因子聚类为6个亚家族,其中亚家族Ⅲ序列结构较为多样性;进化分析发现NAC转录因子存在片段重复和串联重复等复制模式,没有发生近代的全基因组复制事件,并在进化过程中受到纯化选择作用;NAC转录因子基因在哈氏黄瓜幼苗根中表达量最高,其次为雌花和叶片;荧光定量分析发现,低温处理下,检测的15个NAC基因中有12个显著上调表达,3个下调表达,并存在一组表达量差异明显的HdNAC32–HdANC47片段复制基因对。由此可知NAC转录因子在受低温胁迫的哈氏黄瓜中发挥重要的转录调控作用。

关键词: 黄瓜, 哈氏黄瓜, NAC转录因子, 低温胁迫, 基因表达

Abstract: The hardwickii(Cucumis sativus var. hardwickii)is recognized as the wild ancestor of cultivated cucumber,and plays an important role in cucumber genetics and cultivar improvement. In this study,a total of 77 NAC transcription factors were identified with methods of bioinformatics based on sequencing hardwickii genome. The NAC transcription factors were highly conserved. The length of sequences varied and ranged from 151 to 653 amino acids,and unevenly distributed in seven chromosomes. The theoretical isoelectric point(pI)ranged from 4.54 to 9.10. Most of NAC transcription factors were located in the cell nucleus and plasma membrane. Phylogenetic analysis showed that NAC proteins could be classified into six subfamilies,of which the third subfamily exhibited structural diversity. Evolutionary analysis indicated that segmental and tandem duplication events had occurred under the purifying selection pressure,while no recent whole-genome duplication(WGD)events were found in NAC transcription factors. Tissue-specific expression analysis showed that most of genes were highly expressed in root,followed by the female flowers and leaves. In addition,12 up-regulated NAC genes and 3 down-regulated NAC genes were identified under low temperature treatment via RT-PCR. Among which,HdNAC32 and HdANC47,a pair of segmental duplication genes,showed opposite expression patterns. Thus the conclusion was drawn out that NAC transcription factors play a critical role in the transcriptional regulation of cold tolerance in hardwickii under cold stress.

Key words: cucumber, hardwickii, NAC transcription factor, cold stress, gene expression