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Further studies on sugar transporter (SWEET) genes in wheat (Triticum aestivum L.)

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Abstract

SWEET proteins represent one of the largest sugar transporter family in the plant kingdom and play crucial roles in plant development and stress responses. In the present study, a total of 108 TaSWEET genes distributed on all the 21 wheat chromosomes were identified using the latest whole genome sequence (as against 59 genes reported in an earlier report). These 108 genes included 14 of the 17 types reported in Arabidopsis and also included three novel types. Tandem duplications (22) and segmental duplications (5) played a significant role in the expansion of TaSWEET family. A number of cis-elements were also identified in the promoter regions of TaSWEET genes, indicating response of TaSWEET genes during development and also during biotic/abiotic stresses. The TaSWEET proteins carried 4–7 trans-membrane helices (TMHs) showing diversity in structure. Phylogenetic analysis using SWEET proteins of wheat and 8 other species gave four well-known clusters. Expression analysis involving both in silico and in planta indicated relatively higher expression of TaSWEET genes in water/heat sensitive and leaf rust resistant genotypes. The results provided insights into the functional role of TaSWEETs in biotic and abiotic stresses, which may further help in planning strategies to develop high yielding wheat varieties tolerant to environmental stresses.

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Acknowledgements

The work was carried out, when TG and GS held JRF/SRF positions under a research project funded under NASF-ICAR program of Government of India. PKG was awarded Hony Scientist position and HSB was awarded Senior Scientist position both from Indian National Science Academy (INSA). For qRT-PCR, RNA for a pair of NILs was available from another collaborative project funded by NASF-ICAR. Bioinformatics Infrastructure Facility (BIF) laboratory was used for carrying out a part of the bioinformatics work. Head, Department of Genetics and Plant Breeding, CCS University, Meerut, provided the necessary infrastructure.

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  1. Department of Genetics and Plant Breeding, Ch. Charan Singh University, Meerut, 250004, India

    Tinku Gautam, Gautam Saripalli, P. K. Sharma, H. S. Balyan & P. K. Gupta

  2. Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, 110021, India

    Vijay Gahlaut

  3. Advance Center for Computational & Applied Biotechnology, Uttarakhand Council for Biotechnology (UCB), Dehradun, India

    Anuj Kumar

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  1. Tinku Gautam
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PKG, HSB and PKS conceived the experiment and also edited and finalized the manuscript. TG conducted most of the experiments including qRT-PCR with the help of GS. AK conducted molecular dynamics analysis and VG helped in chromosome mapping.

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Correspondence to P. K. Gupta.

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Gautam, T., Saripalli, G., Gahlaut, V. et al. Further studies on sugar transporter (SWEET) genes in wheat (Triticum aestivum L.). Mol Biol Rep 46, 2327–2353 (2019). https://doi.org/10.1007/s11033-019-04691-0

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