, Volume 246, Issue 5, pp 1019–1028 | Cite as

Altered expression of the TaRSL2 gene contributed to variation in root hair length during allopolyploid wheat evolution

  • Haiming Han
  • Huifang Wang
  • Yao Han
  • Zhaorong Hu
  • Mingming Xin
  • Huiru Peng
  • Yingyin Yao
  • Qixin Sun
  • Zhongfu NiEmail author
Original Article


Main conclusion

Altered expression of the TaRSL2 gene was positively correlated with variation in root hair length during allopolyploid wheat evolution, and overexpression of TaRSL2 in Arabidopsis increases root hair length.

Root hairs aid nutrient and water uptake and anchor the plant in the soil. Allopolyploid wheats display significant growth vigor in terms of root hair length compared to their diploid progenitors, but little is known about the molecular basis of variation in root hair length during wheat allopolyploidization. Here, we isolated three orthologs of the Arabidopsis root hair gene ROOT HAIR DEFECTIVE SIX-LIKE 2 (AtRSL2) in allohexaploid wheat, designated TaRSL2-4A, TaRSL2-4B and TaRSL2-4D. The deduced polypeptides of these three TaRSL2 homoeologous genes shared high similarity, and a conserved basic helix-loop-helix (bHLH) domain was present in their C-terminal regions. Notably, the expression of TaRSL2 was positively correlated with root hair length of wheat accessions with different ploidy levels. Moreover, ectopic overexpression of TaRSL2-4D in Arabidopsis could increase root hair length. We found that the transcript levels of TaRSL2 homoeologous genes dynamically changed during allopolyploid wheat evolution, implicating the complexity of the underlying molecular mechanism. Collectively, we propose that altered expression of the TaRSL2 gene contributed to variation in root hair length in allopolyploid wheats.


Gene expression Polyploidization ROOT HAIR DEFECTIVE SIX-LIKETriticum aestivum 



Basic helix-loop-helix





This research was supported by grants from the Major Program of the National Natural Science Foundation of China (31290212) and the National Key Research and Development Program of China (Grant No. 2016YFD0100801).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflicts of interest.

Supplementary material

425_2017_2735_MOESM1_ESM.pdf (2.5 mb)
Supplementary material 1 (PDF 2539 kb)


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Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  • Haiming Han
    • 1
  • Huifang Wang
    • 1
  • Yao Han
    • 1
  • Zhaorong Hu
    • 1
  • Mingming Xin
    • 1
  • Huiru Peng
    • 1
  • Yingyin Yao
    • 1
  • Qixin Sun
    • 1
  • Zhongfu Ni
    • 1
    Email author
  1. 1.State Key Laboratory for Agrobiotechnology, Key Laboratory of Crop Heterosis and Utilization (MOE), Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina

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