Genome-wide identification and expression analysis of the E2 gene family in potato

  • Weigang Liu
  • Xun Tang
  • Xi Zhu
  • Xuehong Qi
  • Ning ZhangEmail author
  • Huaijun Si
Original Article


E2 (ubiquitin conjugating enzymes) is an important part of the ubiquitin–proteasome pathway. These enzymes have a significant role to play during plant growth and development, which can response to various stresses. To date, the E2 family has been reported in some high plants, but the genome-wide characterization of this gene family in potato remains unknown. In the present study, 57 putative StUBCs were identified, which were clustered into eight subgroups based on phylogeny. The introns varied in numbers 0 to 9. The highest numbers of introns were 5, which accounted for 31.57%. The analysis of gene duplication showed that 22 StUBC genes were involved in 13 segmental duplication events, while no tandem duplication was found in StUBC genes. According to gene ontology analysis (GO), StUBC family major function is protein binding and ion binding. The RNA sequencing data revealed that 15 StUBC genes were highly expressed in different organs and tubers. 27 StUBC genes were up-regulated under 50 µM ABA treatments. Moreover, the RNA-seq data and qRT-PCR analysis indicated that 17 StUBC genes responded to heat stress. 8 StUBC genes responded to salt stress according to qRT-PCR analysis, and StUBC2, StUBC12, StUBC30 and StUBC13 were predominant expression. The result of this research could provide valuable information to insight into potato E2 family and establish a foundation for further to elucidate function of E2 genes.


Genome-wide Potato E2 ubiquitin conjugating enzymes Expression analysis 



This research was supported by the National Natural Science Foundation of China (31660416, 31860399) and Discipline Construction Fund Project of Gansu Agricultural University (GSAU-XKJS-2018-169).

Compliance with ethical standards

Conflict of interest

The authors declare no conflict of interest.

Supplementary material

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Distribution information of E2 genes on 12 chromosomes. We renamed StUBC1-StUBC56 according to its order of appearance on the chromosome. The gene that was not located on the chromosomal location was renamed StUBC57.
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Copyright information

© Springer Nature B.V. 2018

Authors and Affiliations

  • Weigang Liu
    • 1
  • Xun Tang
    • 1
    • 2
  • Xi Zhu
    • 1
    • 2
  • Xuehong Qi
    • 1
  • Ning Zhang
    • 1
    Email author
  • Huaijun Si
    • 1
    • 2
  1. 1.College of Life Science and TechnologyGansu Agricultural UniversityLanzhouPeople’s Republic of China
  2. 2.Gansu Provincial Key Laboratory of Aridland Crop Science, Gansu Key Laboratory of Crop Genetic and Germplasm EnhancementGansu Agricultural UniversityLanzhouPeople’s Republic of China

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