Aug 2026· Plant Science· Vol 372, pp.
113398
· 0 citations· 60 references
Medicine
TL;DR
This study elucidates the multifaceted roles of GmCXE31 in coordinating soybean salt tolerance, lipid metabolism and agronomic traits, providing theoretical and genetic resources for salt-tolerant and high-quality soybean molecular breeding.
Abstract
KEY MESSAGE
GmCXE31 negatively regulates salt tolerance and lipid synthesis in soybean, and the cxe31-edited lines improve soybean yield and seed quality. Carboxylesterases (CXEs), as essential lipid hydrolases of the α/β-hydrolase fold superfamily, are critical for plant stress responses, hormone signaling and secondary metabolism. The key candidate gene GmCXE31 was previously identified in our laboratory through a genome‑wide association study (GWAS) of soybean lipid‑related traits. In the present study, we further identified 60 GmCXE family genes in soybean. Phylogenetic analysis clustered them into 11 conserved subfamilies. Cis-acting element analysis showed their promoters are enriched with elements related to abiotic stress, growth and hormone signaling, suggesting potential roles in soybean development and stress adaptation. GmCXE31 is highly expressed in seedling roots and responsive to strigolactones (SLs) and salt stress. Functional assays revealed that GmCXE31 negatively regulates soybean salt tolerance: its overexpression reduced salt tolerance in Arabidopsis and soybean under 150mM NaCl stress, while its knockout enhanced this trait. Lipid profiling revealed GmCXE31-edited lines had higher seed oil content, elevated oleic/linoleic acid ratio and lower saturated fatty acid proportion, which was achieved by regulating lipid synthesis-related genes like GmNFYA. Agronomic trait analysis showed GmCXE31-edited lines had increased nodule number, plant height and single-plant yield at maturity, with opposite phenotypes in overexpression lines. In conclusion, this study elucidates the multifaceted roles of GmCXE31 in coordinating soybean salt tolerance, lipid metabolism and agronomic traits, providing theoretical and genetic resources for salt-tolerant and high-quality soybean molecular breeding.
Carboxylesterases (CXEs) participate in diverse plant metabolic processes, including isoflavone biosynthesis. However, the soybean GmCXE subfamily remains poorly characterized, especially in relation to root isoflavone accumulation and the response to Fusarium oxysporum. Here, fifty-six putative GmCXE genes were identified in the soybean genome and classified into three major phylogenetic clades. Analyses of gene structure, conserved motifs, protein domains, and promoter cis-elements revealed conserved features as well as potential functional divergence among subfamily members. Collinearity and duplication analyses indicated that segmental duplication was the main driver of GmCXE subfamily expansion. Tissue-specific expression profiling and RT-qPCR validation selected five root-expressed genes as candidates associated with isoflavone accumulation. SNP variation analysis and allelic group analysis of 209 soybean accessions further prioritized GmCXE54 as a candidate gene for root isoflavone accumulation. Allelic groups defined by a putative promoter SNP, Chr.20-rs39215413, showed significant differences in root daidzein and total isoflavone contents, with accessions carrying the C allele exhibiting higher levels of both traits than those carrying the T allele. Functional analysis in soybean hairy roots showed that GmCXE54 overexpression increased daidzein and total isoflavone accumulation. At 3 h after F. oxysporum inoculation, GmCXE2, GmCXE39, and GmCXE54 were induced, with GmCXE54 showing the strongest response in the resistant accession ZD27. These findings clarify GmCXE subfamily evolution and identify GmCXE54 as a candidate gene associated with root isoflavone accumulation and early F. oxysporum response, offering new perspectives for improving soybean isoflavone-related traits and investigating root response mechanisms.
This study systematically characterizes the composition, expansion and stress response patterns of the GmATG gene family, revealing functional differentiation among family members.
First comprehensive characterization of the RLCK gene family in sugarcane is presented, elucidating its evolutionary features, expression dynamics and functional roles, and providing compelling evidence that ScRLCK53 modulates salt tolerance through activation of the JA signaling pathway.
Shichao Wang, Pingping Lin, Deng Wu et al.· Plant physiology and biochem...· 0 citations
The SWEET (Sugars Will Eventually be Exported Transporter) family, a class of sugar transporters identified in recent years, plays important roles in plant growth and development. Increasing evidence suggests that SWEET genes are also involved in plant responses to abiotic stresses, including salt stress. However, the genome-wide composition and salt-responsive functions of SWEET genes in Elymus nutans Griseb. have not been systematically characterized to date. This study presents the first genome-wide identification of the SWEET gene family in E. nutans and functional characterization of EnSWEET15 in salt stress response, providing candidate genes and a theoretical basis for improving salt tolerance in this species. A total of 12 EnSWEET genes were identified from the E. nutans genome and were unevenly distributed across eight chromosomes. Phylogenetic analysis classified them into four subfamilies, and promoter analysis revealed abundant cis-elements related to hormone signaling and stress responses, suggesting roles in abiotic stress adaptation. Expression analysis showed that EnSWEET15 was significantly upregulated in both roots and leaves under salt stress. The full-length EnSWEET15 coding sequence (930 bp ORF) was cloned and functionally characterized. Heterologous overexpression in Arabidopsis thaliana indicated that EnSWEET15 enhances salt tolerance. Transgenic lines showed reduced reactive oxygen species (ROS) accumulation and increased activities of antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), compared with wild-type plants under salt stress. Overall, this study identifies EnSWEET15 as a positive regulator of salt tolerance via modulating ROS homeostasis, providing novel insights into SWEET-mediated salt stress response in perennial forages and valuable genetic resources for salt-tolerant breeding of E. nutans.
Functional characterization demonstrated that transgenic tobacco plants overexpressing AsGRF17 displayed significantly enhanced drought tolerance compared with wild-type plants, and this study provides new insights into the molecular mechanisms underlying AsGRF17 -mediated drought tolerance in oat.
Jingyan Li, Shi Tong, Kailian Li et al.· 0 citations
Introduction Aspartate kinase (AK) functions as a key regulatory enzyme in seed development and amino acid metabolism in plants. Although soybean (Glycine max) is a model high protein crop rich in essential amino acids, systematic characterization of its AK gene family remains limited. Methods To identify AK family genes at the genome wide level and analyze their functions, we performed a comprehensive bioinformatic analysis of the soybean genome, including phylogenetic reconstruction, promoter cis element prediction, transcriptomic profiling, and subcellular localization via GFP fusion assays. Functional validation was conducted using GmAK6 overexpressing transgenic soybean lines, with amino acid profiles quantified by HPLC. Results A total of 16 GmAK genes were identified, unevenly distributed across 10 chromosomes, with segmental duplication as the primary evolutionary driver of family expansion. Promoter analysis revealed that nearly half of the cis acting elements are associated with phytohormone signaling (e.g., jasmonic acid, abscisic acid) and abiotic stress responses (e.g., wounding, low temperature). Transcriptomic data showed distinct spatiotemporal expression patterns, with GmAK5 and GmAK6 significantly upregulated during seed development. GmAK6 was localized to chloroplasts. Amino acid profiling of GmAK6 overexpressing seeds demonstrated increased accumulation of methionine, threonine, and cysteine, alongside reduced levels of glutamate and proline. Discussion These results suggest that GmAK6 plays a regulatory role in amino acid metabolism during seed development and highlight the functional importance of AK genes in soybean.
Chao Fan, Wenwei Liang, Wei Li et al.· Frontiers in Plant Science· 0 citations
