Plant Diversity ›› 2021, Vol. 43 ›› Issue (06): 510-522.DOI: 10.1016/j.pld.2020.10.004

• Articles • Previous Articles    

Genome-wide identification and expression analysis of NtbHLH gene family in tobacco (Nicotiana tabacum) and the role of NtbHLH86 in drought adaptation

Ge Baia,b,c, Da-Hai Yanga,b,c, Peijian Chaod, Heng Yaoa,b,c, MingLiang Feia,b,c, Yihan Zhanga,b,c, Xuejun Chena,b,c, Bingguang Xiaoa,b,c, Feng Lid, Zhen-Yu Wange, Jun Yangd, He Xiea,b,c   

  1. a Tobacco Breeding and Biotechnology Research Center, Yunnan Academy of Tobacco Agricultural Sciences, Kunming, Yunnan, China;
    b Key Laboratory of Tobacco Biotechnological Breeding, Kunming, Yunnan, China;
    c National Tobacco Genetic Engineering Research Center, Kunming, Yunnan, China;
    d National Tobacco Gene Research Centre, Zhengzhou Tobacco Research Institute, Zhengzhou, Henan, China;
    e Institute ofBioengineering, Guangdong Academy of Sciences, Guangzhou, Guangdong, 510316, China
  • Received:2020-09-16 Revised:2020-10-12 Online:2021-12-25 Published:2022-01-11
  • Contact: Jun Yang, He Xie
  • Supported by:
    This work was funded by the National Natural Science Foundation of China (grant number 31760072 to G. Bai, and grant number 31860413 to H. Xie) and Yunnan Applied Basic Research Project (grant number 202001AT070010 to G. Bai) and the Yunnan Academy of Tobacco Agricultural Sciences (grant numbers YNTC-2016YN22 and CNTC-110202001025(JY08) to H. Xie, YNTC-2016YN24, YNTC-2015YN02, YNTC-2018530000241002, and YNTC-2019530000241003 to D.-H. Yang).

Abstract: The bHLH transcription factors play pivotal roles in plant growth and development, production of secondary metabolites and responses to various environmental stresses. Although the bHLH genes have been well studied in model plant species, a comprehensive investigation of the bHLH genes is required for tobacco with newly obtained high-quality genome. In the present study, a total of 309 NtbHLH genes were identified and can be divided into 23 subfamilies. The conserved amino acids which are essential for their function were predicted for the NtbHLH proteins. Moreover, the NtbHLH genes were conserved during evolution through analyzing the gene structures and conserved motifs. A total of 265 NtbHLH genes were localized in the 24 tobacco chromosomes while the remained 44 NtbHLH genes were mapped to the scaffolds due to the complexity of tobacco genome. Moreover, transcripts of NtbHLH genes were obviously tissue-specific expressed from the gene-chip data from 23 tobacco tissues, and expressions of 20 random selected NtbHLH genes were further confirmed by quantitative real-time PCR, indicating their potential functions in the plant growth and development. Importantly, overexpressed NtbHLH86 gene confers improve drought tolerance in tobacco indicating that it might be involved in the regulation of drought stress. Therefore, our findings here provide a valuable information on the characterization of NtbHLH genes and further investigation of their functions in tobacco.

Key words: bHLH gene family, Development, Genome-wide analysis, Characterization