The XTH Gene Family in Schima superba: Genome-Wide Identification, Expression Profiles, and Functional Interaction Network Analysis

Abstract

Xyloglucan endotransglucosylase/hydrolase (XTH), belonging to glycoside hydrolase family 16, is one of the key enzymes in plant cell wall remodeling. Schima superba is an important timber and fireproof tree species in southern China. However, little is known about XTHs in S. superba. In the present study, a total of 34 SsuXTHs were obtained, which were classified into three subfamilies based on the phylogenetic relationship and unevenly distributed on 18 chromosomes. Furthermore, the intron–exon structure and conserved motif composition of them supported the classification and the members belonging to the same subfamily shared similar gene structures. Segmental and tandem duplication events did not lead to SsuXTH gene family expansion, and strong purifying selection pressures during evolution led to similar structure and function of SsuXTH gene family. The interaction network and cis-acting regulatory elements analysis revealed the SsuXTH expression might be regulated by multiple hormones, abiotic stresses and transcription factors. Finally, expression profiles and GO enrichment analysis showed most of the tandem repeat genes were mainly expressed in the phloem and xylem and they mainly participated in glycoside metabolic processes through the transfer and hydrolysis of xyloglucan in the cell wall and then regulated fiber elongation.

Genome-wide characterization of the xyloglucan endotransglucosylase/hydrolase gene family in Solanum lycopersicum L. and gene expression analysis in response to arbuscular mycorrhizal symbiosis

“…Conserved motifs analysis indicates that SlXTHs from subfamily I/II and III have ten conserved motifs, whereas SlXTH31 and SlXTH36 from subfamily I/II have only six and seven, respectively. This is consistent with previous reports for other XTHs ( Behar, Graham & Brumer, 2018 ; Wu et al, 2020 ; Qiao et al, 2022 ; Yang, Zhang & Zhou, 2022 ).…”

“…Furthermore, based on the release of the tomato genome ( The Tomato Genome Consortium, 2012 ), we identified 37 SlXTH gene members by genome-wide screening. Consistent with this, large numbers of XTHs have been found in other plant species ( Yokoyama & Nishitani, 2001 ; Yokoyama, Rose & Nishitani, 2004 ; Saladié et al, 2006 ; Atkinson et al, 2009 ; Rai et al, 2016 ; Song et al, 2018 ; Wang et al, 2018 ; Fu, Liu & Wu, 2019 ; Li et al, 2019 ; Wu et al, 2020 ; Zhu et al, 2022 ; Qiao et al, 2022 ; Yang, Zhang & Zhou, 2022 ).…”

“…Different numbers of XTH genes have been identified and characterized in plant species such as Arabidopsis thaliana (33 genes; Yokoyama & Nishitani, 2001 ), Oryza sativa (29 genes; Yokoyama, Rose & Nishitani, 2004 ), Sorghum bicolor (35 genes; Rai et al, 2016 ), Hordeum vulgare (24 genes; Fu, Liu & Wu, 2019 ), Actinidia deliciosa (14 genes; Atkinson et al, 2009 ), Malus domestica (11 genes; Atkinson et al, 2009 ), Glycine max (61 genes; Song et al, 2018 ), Solanum lycopersicum (25 genes; Saladié et al, 2006 ), Ananas comosus (48 genes; Li et al, 2019 ), Brassica rapa (53 genes; Wu et al, 2020 ), Brassica oleracea (38 genes; Wu et al, 2020 ), Nicotiana tabacum (56 genes; Wang et al, 2018 ), Vitis vinifera L. (34 genes; Qiao et al, 2022 ), Arachis hypogaea L. (58 genes; Zhu et al, 2022 ) and Schima superba (34 genes; Yang, Zhang & Zhou, 2022 ).…”

CiXTH29 and CiLEA4 Role in Water Stress Tolerance in Cichorium intybus Varieties

“…The amount of CiXTH29 basal expression in Galatina, even if higher than Brindisina, Esportazione and Rossa Italiana, could be not high enough to protect the plant from water stress damage. The high basal expression levels of XTH29 in chicory varieties (Selvatica, Zuccherina di Trieste and Galatina) is certainly an important feature, since XTH29 is known to be poorly expressed in Arabidopsis [ 65 ], in Brassica [ 66 ] and, as shown recently, in the roots and fruits of Schima superba [ 67 ]. Nevertheless, several pieces of evidence demonstrate an important role of XTHs in drought stress, as reported in Medicago truncatula [ 68 ], Arabidopsis [ 26 , 29 ], tomato [ 27 ], grapevine [ 69 ] and Salicornia aeuropaea [ 70 ].…”

Genome-wide identification of XTH genes in Liriodendron chinense and functional characterization of LcXTH21

“…Due to their important roles in drought stress and growth, XTH family members have been identified in various plants, including A. thaliana (33 genes), Oryza sativa (29 genes), Hordeum vulgare (24 genes), Populus spp. (41 genes), Ananas comosus (24 genes), and Schima superba (34 genes) ( Yokoyama and Nishitani, 2001 ; Yokoyama et al., 2004 ; Geisler-Lee et al., 2006 ; Fu et al., 2019 ; Li et al., 2019 ; Yang et al., 2022 ).…”