Isolation and characterization of water-deficit stress-responsive α-expansin 1 (EXPA1) gene from Saccharum complex

Abstract

In this study, full-length (1282-1330 bp) α-expansin 1 (EXPA1) gene from three different accessions belonging to Saccharum complex (Saccharum officinarum-SoEXPA1, Erianthus arundinaceus-EaEXPA1, and Saccharum spp. hybrid-ShEXPA1) was isolated using RAGE technique and characterized. The intronic and coding regions of isolated expansin genes ranged between 526-568 and 756-762 bp, respectively. An open reading frame encoding a polypeptide of 252 amino acids was obtained from S. officinarum and commercial sugarcane hybrid, whereas 254 amino acids were obtained in E. arundinaceus, a wild relative of Saccharum. Bioinformatics analysis of deduced protein revealed the presence of specific signature sequences and conserved amino acid residues crucial for the functioning of the protein. The predicted physicochemical characterization showed that the protein is stable in nature with instability index (II) value less than 40 and also clearly shown the dominance of random coil in the protein structure. Phylogenetic analysis revealed high conservation of EXPA1 among Saccharum complex and related crop species, Sorghum bicolor and Zea mays. The docking study of EXPA1 protein showed the interaction with xylose, which is present in xyloglucan of plant cell wall, elucidated the role of the expansin proteins in plant cell wall modification. This was further supported by the subcellular localization experiment in which it is clearly seen that the expansin protein localizes in the cell wall. Relative expression analysis of EXPA1 gene in Saccharum complex during drought stress showed high expression of the EaEXPA1 in comparison with SoEXPA1 and ShEXPA1 indicating possible role of EaEXPA1 in increased water-deficit stress tolerance in E. arundinaceus. These results suggest the potential use of EXPA1 for increasing the water-deficient stress tolerance levels in crop plants.

Expansin-mediated developmental and adaptive responses: A matter of cell wall biomechanics?

“…The transcripts of many α-expansins are up-regulated under abiotic stress (Marowa et al, 2016 ; Tenhaken, 2015 ). Accordingly, genetic approaches have shown that enhanced expansin expression might contribute to stress tolerance to drought (Chen et al, 2016 ; Hao et al, 2017 ; Liu et al, 2019 ; Narayan et al, 2019 ; Yang et al, 2020 ), high salinity (Chen et al, 2017 ; 2018a ; Hao et al, 2017 ; Lu et al, 2013 ; Yan et al, 2014 ; Zhang et al, 2019b ), heat (Xu et al, 2007 ; 2014 ), cold (Peng et al, 2019 ; Zhang et al, 2018a ), oxidative (Chen et al, 2018b ) and heavy metal (cadmium) stress (Ren et al, 2018 ; Zhang et al, 2018b ). Moreover, Han et al ( 2012 ; 2015 ) described that overexpression of -expansin TaEXPB23 also enhanced tolerance to oxidative and salt stress, similar to the -expansins ZmEXPB6 and ZmEXPB8 studied by Geilfus et al ( 2015 ) and Wu et al ( 2001 ) respectively.…”

Reproductive developmental transcriptome analysis of Tripidium ravennae (Poaceae)

“…The members of the expansin family were significantly over-represented in the hypergeometric annotation tests as well as the differential expression analysis, which identified nine different transcript annotations of expansins as well as other canonical floral induction integrators. As culms produced new vertical growth, the upregulation of multiple expansin family members validated their role in the reproductive process of Tripidium [ 71 – 73 ].…”

Isolation, characterization and expression analysis of stress responsive plant nuclear transcriptional factor subunit (NF-YB2) from commercial Saccharum hybrid and wild relative Erianthus arundinaceus

“…In a perspective of understanding the role of NF-YB2 subunit in drought and salinity stress response, NF-YB2 from E. arundinaceus, a wild relative of Saccharum, a known source of drought and salinity stress tolerance (Augustine et al 2015b;Valarmathi et al 2018;Manoj et al 2019;Ashwin Narayan et al 2019) and commercial Saccharum hybrid Co 86032 was isolated and characterized. The isolated EaNF-YB2 and ShNF-YB2, each of 543 bp, predicted to encode a protein of 180 amino acid residues which shared identity of 97% with S. bicolor NF-YB2 and 93% identity with Z. mays NF-YB2 with 100% query coverage.…”

“…A successful hybridization between Saccharum spp hybrids and Erianthus species, and the presence of Erianthus chromosomes in intergeneric hybrids have been reported (D'Hont et al 1995;Piperidis et al 2000Piperidis et al , 2010Nair et al 2017;Premachandran et al 2017). E. arundinaceus is well known for its tolerance to abiotic stresses (Ram et al 2001;Augustine et al2015a, b, c;Anunanthini et al 2019;Ashwin Narayan et al 2019;Deng et al 2019;Manoj et al 2019) and has become a powerful genetic resource for the genetic improvement of the sugarcane varieties. It has been reported that drought and salinity induce many stress-responsive mechanisms regulated by various genes which include genes encoding transcription factors (TFs).…”