Xiaoli Tang

SINA (Seven in Absentia) E3 ubiquitin ligase represents a major class of E3 ligase in the ubiquitin‑proteasome system (UPS) and play critical roles in diverse plant physiological processes. In this study, the kiwifruit (Actinidia chinensis Planch.) AcSINA1 was systematically investigated via bioinformatics, spatiotemporal and stress-responsive expression profiles, and functional analyses. Bioinformatics analysis revealed that AcSINA1 was located on kiwifruit chromosome 3 and encoded a 317 amino acid protein, with a predicted molecular weight of 35 848.65 Da and an isoelectric point of 6.54. Meanwhile, AcSINA1 protein harbored the conserved RING and SINA domains and shared the closest phylogenetic relationship with rice OsSINA3. The gene promoter was enriched in stress and hormone responsive cis‑elements, including elements responsive to abscisic acid (ABA), methyl jasmonate (MeJA), salicylic acid (SA), light, and anaerobic induction. Expression analysis showed that AcSINA1 exhibited the highest transcript abundance in kiwifruit stems. The expression profiling under multiple treatments suggested that AcSINA1 showed significant expression changes in response to ABA, cold, and salt stresses. The GUS staining assay further proofed that AcSINA1 were predominantly expressed in stems and lateral root tips of transgenic Arabidopsis. Functional research revealed that compared with wild type, the transgenic Arabidopsis had a higher germination rate, greater shoot fresh weight, and longer primary root length under ABA treatment at both germination and vegetative stages. These findings enrich our knowledge of plant SINA proteins and lay foundation for breeding new salt-tolerant cultivars.

The XYLP family is reported to be essential for the regulation of growth and development, mediating plant hormone signals, and promoting adaptation to environmental stresses across various plant species. Although the XYLP family in Actinidia chinensis (kiwifruit) enhances the understanding of developmental processes and abiotic stress responses, a systematic analysis of this gene family remains lacking. In this study, 28 AcXYLP genes were identified in the kiwifruit genome, which were classified into five clades based on a phylogenetic tree. Collinearity analysis revealed that the expansion of AcXYLP genes was predominantly influenced by segmental genome duplication events. Gene ontology and protein–protein interaction network analysis indicated that AcXYLP genes were involved in pathways related to plant growth, developmental process, and abiotic stresses responses. The promoter regions harboring cis-acting elements associated with plant growth and development, phytohormones, and stress responses, highlighting the significant roles of the AcXYLP gene family. Expression profile analysis of 28 AcXYLP genes in different tissues revealed their tissue-specific functions. Notably, AcXYLP13, AcXYLP15 and AcXYLP27 were identified as top-ranked nodes in STRING-predicted network protein involved in plant growth and abiotic stress responses, indicating their central roles in coordinating developmental signaling and stress responses. This study facilitated further exploration of the functional characteristics of AcXYLP genes.

The size of leaves and fruits is a crucial agronomic and economic trait for fruit trees. The ‘Bartlett’ pear is a famous cultivar with succulent and delicious fruit and is cultivated globally. ‘Xiang shuomi’ is a bud sport of the ‘Bartlett’ pear, discovered in our breeding work, and exhibits enlarged leaves and fruits. However, the specific regulatory mechanism of this superior agronomic trait is still elusive. In this study, comprehensive transcriptome and metabolome analyses were performed to explore the differences in gene expression and metabolite accumulation between these two pear cultivars. The transcriptome analysis showed a total of 1279 differentially expressed genes (DEGs), with the flavonoid biosynthetic process being the most significant enriched biological process. Metabolome data indicated the detection of 412 differentially abundant metabolites (DAMs), with the metabolites of flavonoid biosynthesis being enriched significantly. The integrative transcriptomic and metabolomics analysis further confirmed the pivotal role of the flavonoid biosynthetic process in distinguishing the two cultivars. Importantly, the genes that encoded enzymes related to flavonoid biosynthesis, including CHS, CHI, HCT, LAR and CYP75B1, increased their expressions in the ‘Xiang shuomi’ pear. Correspondingly, the metabolites galangin, chlorogenic acid, luteolin and catechin were found to accumulate in the ‘Xiang shuomi’ pear. Overall, this research identified key pathways and genes influencing the fruit and leaf size of pears, providing fundamental information for the high-yield breeding of fruit trees.

Background: Respiratory health is closely related to immune system function, and diet can also influence immune homeostasis. Diet, an important part of a healthy lifestyle, is also linked to respiratory health. We aimed to explore the relationship between different dietary patterns and the risk of chronic respiratory diseases (CRDs), including chronic bronchitis (CB), emphysema, and asthma.Method: A total of 23,042 adults from the United States were selected from the National Health and Nutrition Examination Survey (NHANES) dataset between 2007 and 2018. Diet quality was assessed using 2-day, 24-hour dietary recall data and quantified as the Healthy Eating Index-2020 (HEI-2020), the Dietary Inflammation Index (DII), the Mediterranean Dietary Index (MEDI), and the Dietary Approaches to Stop Hypertension Index (DASHI). Binary logistic regression models, restricted cubic splines (RCS), and the weighted quartile sum (WQS) models were used to assess the relationship between diet quality and the risk of CB, emphysema, and asthma.Results: In logistic regression analyses of the four dietary indices with the three chronic respiratory diseases, it was consistently observed that higher dietary quality scores were linked to a reduced risk of respiratory disease. These consistent trends were also evident in the assessments of the dose–response relationship between dietary quality score and the risk of respiratory disease. Furthermore, evaluations of the combined effects of dietary components across different dietary indices in the risk of chronic respiratory disease yielded results consistent with the logistic regression models. Notably, high-quality protein, minerals, and fiber-rich fruits and vegetables emerged as the food groups making the most significant contributions to health across different dietary indices.Conclusion: Low-quality diets, lacking in high-quality protein, minerals, and fruits and vegetables rich in dietary fiber, are associated with a higher risk of chronic respiratory disease, regardless of the dietary index used to measure diet quality.

SINA (Seven in absentia) proteins in the subtype of E3 ubiquitin ligase family play a crucial role in plant growth and development. However, their functions in response to salt and osmotic stresses in oil crops are still largely unknown. In this study, a total number of 23 BnaSINAs were identified in the rapeseed genome. Chromosome location and collinear relationship analyses revealed that they were unevenly distributed on 13 chromosomes, and have gone through 22 segmental duplication events under purifying selection. Phylogenetic and gene structural analyses indicated that they belonged to five main groups, and those in the same subgroup showed similar gene structure. All BnaSINAs were predicted to form homo- or heterodimers. Except BnaSINA7, BnaSINA11, BnaSINA17 and BnaSINA18, which lacked the N-terminal RING finger, all BnaSINAs contained a conserved C-terminal SINA domain, a typical structural feature of the RING-type E3 ligase family. Transcriptional expression analyses demonstrated that most BnaSINAs were ubiquitously expressed in roots, stems, leaves, flowers, pods and seeds, and all were responsive to salt and osmotic stresses. Further, yeast two-hybrid and Arabidopsis mutant complementation analyses demonstrated that BnaSINA4 interacted with BnaSINA17 to form heterodimer, and expression of BnaSINA17 in the Arabidopsis sina2 mutant restored its growth resistance to salt and osmotic stresses. Our findings provide an important genetic foundation for the functional elucidation of BnaSINAs and a novel gene resource for the breeding of new oil crop cultivars with improved abiotic stress resistance.

Small heat shock proteins (sHSPs) are a group of chaperone proteins existed in all organisms. The functions of sHSPs in heat and abiotic stress responses in many glycophyte plants have been studied. However, their possible roles in halophyte plants are still largely known. In this work, a putative sHSP gene KvHSP26 was cloned from K. virginica. Bioinformatics analyses revealed that KvHSP26 encoded a chloroplastic protein with the typical features of sHSPs. Amino acid sequence alignment and phylogenetic analysis demonstrated that KvHSP26 shared 30-77 homology with other sHSPs from Arabidopsis, cotton, durian, salvia, and soybean. Quantitative real-time PCR (qPCR) assays exhibited that KvHSP26 was constitutively expressed in different tissues such as leaves, stems, and roots, with a relatively higher expression in leaves. Furthermore, expression of KvHSP26 was strongly induced by salt, heat, osmotic stress, and ABA in K. virginica. All these results suggest that KvHSP26 encodes a new sHSP, which is involved in multiple abiotic stress responses in K. virginica, and it has a great potential to be used as a candidate gene for the breeding of plants with improved tolerances to various abiotic stresses.

Background: Glycine soja is a halophytic soybean native to saline soil in Yellow River Delta, China. Photosystem I (PSI) performance and the interaction between photosystem II (PSII) and PSI remain unclear in Glycine soja under salt stress. This study aimed to explore salt adaptability in Glycine soja in terms of photosystems coordination. Results: Potted Glycine soja was exposed to 300 mM NaCl for 9 days with a cultivated soybean, Glycine max, as control. Under salt stress, the maximal photochemical efficiency of PSII (Fv/Fm) and PSI (△MR/MR₀) were significantly decreased with the loss of PSI and PSII reaction center proteins in Glycine max, and greater PSI vulnerability was suggested by earlier decrease in △MR/MR₀ than Fv/Fm and depressed PSI oxidation in modulated 820 nm reflection transients. Inversely, PSI stability was defined in Glycine soja, as △MR/MR₀ and PSI reaction center protein abundance were not affected by salt stress. Consistently, chloroplast ultrastructure and leaf lipid peroxidation were not affected in Glycine soja under salt stress. Inhibition on electron flow at PSII acceptor side helped protect PSI by restricting electron flow to PSI and seemed as a positive response in Glycine soja due to its rapid recovery after salt stress. Reciprocally, PSI stability aided in preventing PSII photoinhibition, as the simulated feedback inhibition by PSI inactivation induced great decrease in Fv/Fm under salt stress. In contrast, PSI inactivation elevated PSII excitation pressure through inhibition on PSII acceptor side and accelerated PSII photoinhibition in Glycine max, according to the positive and negative correlation of △MR/MR₀ with efficiency that an electron moves beyond primary quinone and PSII excitation pressure respectively. Conclusion: Therefore, photosystems coordination depending on PSI stability and rapid response of PSII acceptor side contributed to defending salt-induced oxidative stress on photosynthetic apparatus in Glycine soja. Photosystems interaction should be considered as one of the salt adaptable mechanisms in this halophytic soybean.