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

Abstract

Xyloglucan endotransglucosylase/hydrolases (XTHs) are a glycoside hydrolase protein family involved in the biosynthesis of xyloglucans, with essential roles in the regulation of plant cell wall extensibility. By taking advantage of the whole genome sequence in Solanum lycopersicum, 37 SlXTHs were identified in the present work. SlXTHs were classified into four subfamilies (ancestral, I/II, III-A, III-B) when aligned to XTHs of other plant species. Gene structure and conserved motifs showed similar compositions in each subfamily. Segmental duplication was the primary mechanism accounting for the expansion of SlXTH genes. In silico expression analysis showed that SlXTH genes exhibited differential expression in several tissues. GO analysis and 3D protein structure indicated that all 37 SlXTHs participate in cell wall biogenesis and xyloglucan metabolism. Promoter analysis revealed that some SlXTHs have MeJA- and stress-responsive elements. qRT-PCR expression analysis of nine SlXTHs in leaves and roots of mycorrhizal colonized vs. non-colonized plants showed that eight of these genes were differentially expressed in leaves and four in roots, suggesting that SlXTHs might play roles in plant defense induced by arbuscular mycorrhiza. Our results provide valuable insight into the function of XTHs in S. lycopersicum, in addition to the response of plants to mycorrhizal colonization.

Genome-Wide Analysis of the Xyloglucan Endotransglucosylase/Hydrolase (XTH) Gene Family: Expression Pattern during Magnesium Stress Treatment in the Mulberry Plant (Morus alba L.) Leaves

“…Further, phylogenetic analysis indicated that MaXTH protein families were clustered into five groups ( Figure 1 ), similar to those observed for XTH proteins from sweet cherry [ 26 ]. Interestingly, the MaXTH proteins belonging to the same group demonstrated similar gene structures ( Figure 1 ) and conserved sequence expression, which is consistent with previously documented literature [ 11 , 20 ], suggesting that XTH members within the same group may exhibit analogous functionalities. Moreover, most of the MaXTH genes demonstrate the presence of two main conserved domains (Glyco_hydro_16 and XET_C domain) ( Figure 2 ).…”

“…Based on the M. alba genome, 22 XTH genes were identified based on our strictest identification workflow and labeled as MaXTH-1 to MaXTH-22 . The number of identified XTH genes was notably less compared to various other species, including tobacco (56), wheat (71), Solanum lycopersicum (37), and Glycine max (61) [ 11 , 18 , 22 , 52 ]. It is widely acknowledged that the functional attributes of genes are intricately linked to their structural and physicochemical characteristics [ 20 , 56 ].…”

“…In response to these challenges, plants have developed intricate regulatory mechanisms, including the involvement of distinct gene families, such as Xyloglucan endotransglucosylase/hydrolases ( XTH s) [ 10 ]. XTH s genes are classified within the glycoside hydrolase family 16 and are an essential group of enzymes primarily responsible for cleaving and rearranging the xyloglucan backbones within plant cell walls [ 11 , 12 , 13 ]. Specifically, family members of this gene carry out two distinct biochemical processes that are catalyzed by two specific enzymes: xyloglucan endotransglycosylase ( XET ) and xyloglucan endohydrolase ( XEH ) [ 14 ].…”

“…Several XTHs exhibit catalytic properties and play an essential role in regulating the extensibility of plant cell walls, root elongation, and plant growth [11,15]. Due to the advancement of sequencing technology and data availability, an expanding repertoire of XTH genes has been discovered and characterized in a broader range of species including Ananas comosus (48) [16], Arachis hypogaea L. (58) [17], Glycine max (61) [18] Arabidopsis thaliana [19], lpomoea batatas (36) [20], Oryza sativa (29) [21], Solanum lycopersicum L. (37) [11], Nicotiana tabacum (56) [22] Brassica rapa (53) and Brassica oleracea (35) [23]. Nonetheless, the XTH family constituents in mulberry remain undisclosed.…”

Integrated Multi-Omics Analysis to Reveal the Molecular Mechanisms of Inflorescence Elongation in Medicago sativa

“…Plant hormones play an important role in regulating lignin biosynthesis, organic matter accumulation, and other physiological activities and eventually influence the growth and development of plant tissues and organs [ 16 , 17 , 18 ]. Auxins (IAA) are frequently associated with stem elongation and root development and can promote or inhibit apical dominance [ 19 , 20 ].…”