Genome-Wide Identification of Expansin Genes in Wild Soybean (Glycine soja) and Functional Characterization of Expansin B1 (GsEXPB1) in Soybean Hair Root

Abstract

Wild soybean, the progenitor and close relative of cultivated soybean, has an excellent environmental adaptation ability and abundant resistance genes. Expansins, as a class of cell wall relaxation proteins, have important functions in regulating plant growth and stress resistance. In the present study, we identified a total of 75 members of the expansin family on the basis of recent genomic data published for wild soybean. The predicted results of promoter elements structure showed that wild soybean expansin may be associated with plant hormones, stress responses, and growth. Basal transcriptome data of vegetative organs suggest that the transcription of expansin members has some organ specificity. Meanwhile, the transcripts of some members had strong responses to salt, low temperature and drought stress. We screened and obtained an expansin gene, GsEXPB1, which is transcribed specifically in roots and actively responds to salt stress. The results of A. tumefaciens transient transfection showed that this protein was localized in the cell wall of onion epidermal cells. We initially analyzed the function of GsEXPB1 by a soybean hairy root transformation assay and found that overexpression of GsEXPB1 significantly increased the number of hairy roots, root length, root weight, and the tolerance to salt stress. This research provides a foundation for subsequent studies of expansins in wild soybean.

New integrative vectors increaseAgrobacterium rhizogenestransformation and help characterise roles for soybeanGmTMLgene family members

“…Collectively, our findings demonstrate the effectiveness of pHOG13 and pHGUS7 as new tools for enhancing the transformation efficiency of A. rhizogenes K599 in hairy root studies. The K599 strain is effective in transforming several species, including the legumes G. max (soybean; Kereszt et al, 2007;Lin et al, 2011;Zhang et al, 2021;Chu et al, 2022), G. soja (wild soybean; Feng et al, 2022;Li et al, 2024), P. vulgaris (common bean;Estrada-Navarrete et al, 2007;Ferguson et al, 2014), P. sativum (pea; e.g. Li et al, 2023), Lens culinaris (lentil; Foti and Pavli, 2020), Cicer arietinum (chickpea; Aggarwal et al, 2018), Vigna radiata (mungbean; Cuong et al, 2023;Lin et al, 2022;, Vigna unguiculata (cowpea; Ji et al, 2019), Cajanus cajan (pigeon pea; Meng et al, 2019), and non-legumes such as Gossypium hirsutum (cotton; Zhou et al, 2022), citrus species (Ma et al, 2022;Gong et al, 2024), Cucumis sativus (cucumber; Nguyen et al, 2022), Cucurbita moschata (pumpkin; Geng et al, 2022), etc.…”

Harnessing Knowledge from Plant Functional Genomics and Multi-Omics for Genetic Improvement

“…Another study identified 75 members of the expansin ( EXP ) family in wild soybean ( Glycine soja ). In the identified 75 members of the expansin ( EXP ) family, overexpression of GsEXPB1 increased the number of hairy root and tolerance to salt stress [ 4 ]. Sehrish et al identified 122 SET domain genes ( SDGs ) genes in B.napus and characterized their evolution, structure and expression patterns in detail [ 5 ].…”

Overexpression of Wild Soybean Expansin Gene GsEXLB14 Enhanced the Tolerance of Transgenic Soybean Hairy Roots to Salt and Drought Stresses

“…The expansin gene family in wild soybeans may be of great significance for soybean molecular breeding, but related research is scarce. Our research group completed the whole-genome identification of the wild soybean expansin family in a previous study and analyzed the expression patterns of some expansin genes [ 35 ]. Previous studies have shown that GsEXLB14 is specifically transcribed in wild soybean roots, and its transcript levels are significantly upregulated under salt and drought stress treatments.…”