Ruhong Xu

Heavy metal stress is a critical challenge to agricultural productivity, necessitating deeper insights into the molecular mechanisms of metal transport in plants. In this study, we conducted a comprehensive genome-wide characterization of the Natural Resistance-Associated Macrophage Protein (NRAMP) gene family in Arabidopsis thaliana and identified six AtNRAMP genes. Phylogenetic and synteny analyses revealed their distribution into two distinct clades and evolutionary conservation with legumes such as Glycine max and Arachis hypogaea, indicating functional divergence and gene duplication events maintained under purifying selection. Conserved protein motifs and domains, particularly the NRAMP transmembrane domain, highlighted their conserved role in divalent metal ion transport, while cis-regulatory element analysis demonstrated enrichment of stress- and hormone-responsive elements, pointing to tight transcriptional regulation under environmental challenges. Structural modeling further supported the functional conservation of AtNRAMP proteins. Expression profiling showed clear tissue-specific expression under normal conditions and strong, differential regulation in response to cadmium and other heavy metals, as well as to the phytohormone abscisic acid (ABA). Collectively, these results provide foundational insights into the evolutionary relationships, regulatory mechanisms, and stress-responsive expression of the AtNRAMP gene family, offering a framework for future functional studies and potential applications in developing crops with enhanced heavy metal tolerance and improved growth under stress conditions.

Castor (Ricinus communis L.), a member of the Euphorbiaceae family, is a non-edible oilseed crop extensively cultivated in arid and semi-arid regions worldwide for its diverse industrial uses. The B-cell lymphoma 2 (Bcl-2)-associated athanogene (BAG) family is a diverse and well-conserved co-chaperone family present in both plants and mammals. BAG proteins interact with a wide range of proteins, regulating various functions, including stress response, growth, and development. However, the function of BAGs in oilseed crops like castor remains largely unknown. In this study, we discovered 9 BAG protein family members (RcBAGs) in castor through genome-wide scanning. We investigated chromosomal localization, performed in silico promoter analysis, conducted phylogenetic and synteny analyses, and examined gene architecture. Additionally, we predicted protein-protein interactions and assessed the responses of these genes to various abiotic stresses and hormones. Based on their cellular localization, the RcBAG family was categorized into nuclear, chloroplastic, and cytoplasmic groups. Syntenic gene pairs across different crops also validated the importance and functional conservation of these BAG genes during evolution. Furthermore, in Ricinus communis, the RcBAG genes were scattered unevenly throughout seven of the 10 chromosomes. The study reveals that RcBAG genes are crucial for stress management and castor growth, responding to abiotic stimuli through distinct regulatory pathways. Quantitative real-time polymerase chain reaction (qRT-PCR) investigation revealed that 9 distinct RcBAG genes were strongly induced after cold and heat treatments. Functional analysis and protein-protein interactions were used to predict the potential regulatory network of RcBAGs, revealing tight networking and signaling with HSP proteins. This study provides a foundation for future research into the molecular mechanisms and regulatory processes during R. communis growth, development, response to various stressors, and protein interactions.

Introduction Purple wheat (GZ1) is a high-quality wheat variety, and understanding its starch accumulation is key to improving its quality. Investigating how phytohormone regulate starch accumulation during the development of GZ1 grains can shed light on the molecular mechanisms of starch accumulation, supporting optimized wheat production and breeding. This study explored the roles of the phytohormone abscisic acid (ABA) and jasmonic acid (JA) in starch accumulation within purple wheat kernels. Materials and methods Wheat variety GZ1 was cultivated under controlled field conditions, with samples collected at 10, 25, and 35 days post-anthesis for RNA extraction, starch and enzyme activity measurements, paraffin sectioning, phytohormone analysis, and qPCR validation. Results During grain development at 10, 25, and 35 days post-anthesis (dpa), starch content increased progressively, with the rate of accumulation slowing at 35 dpa. The activities of starch biosynthetic enzymes, including GBSS, SSS, and AGPase, increased from 10 to 25 dpa and declined at 35 dpa. Paraffin section analysis revealed enhanced starch granule accumulation across stages, consistent with the results of starch content measurement. ABA levels showed a continuous increase from 10 to 35 dpa, while both JA and JA-Ile levels decreased from 10 to 25 dpa and then increased markedly at 35 dpa. Venn diagram and heat map analyses showed that at 10 dpa, most ABA-related genes were upregulated, while JA-related genes were predominantly downregulated. By 35 dpa, ABA-related genes exhibited widespread downregulation in number, while JA-related genes showed an almost equal split between up- and downregulation. qRT-PCR results confirmed that the expression trends of ABA- and JA-related genes were consistent with transcriptome data. Starch synthesis-related genes, including TPP-7A, AGPS1a, NAC019, and GBSS1, were upregulated in expression between 10 and 25 dpa and downregulated at 35 dpa. Correlation analysis showed that starch content had a strong positive correlation with ABA levels and the activities of starch biosynthetic enzymes (GBSS, SSS, and AGPase). Starch content exhibited a moderate positive correlation with JA levels and no correlation with JA-Ile levels. ABA levels were positively correlated with the activities of the three starch biosynthetic enzymes, while JA content showed a strong positive correlation only with SSS activity. Conclusion This study elucidated the time-dependent regulatory roles of ABA and JA in starch accumulation during the natural development of GZ-1 seeds.

Shading plays an important role in determining nutrient content and yield fo wheat (Triticum aestivum). However, the genetic mechanism underlying the effects of shading treatment on grain filling remains unclear. Therefore, we performed phenotypic and transcriptome analyses on wheat cv. ZY96-3 during grain development under normal and shaded conditions. Shading resulted in a significant decrease in grain size and 1000-grain weight. Correlation analysis revealed the strong effect of shading on the mean and maximum grain-filling rate and secondary grain-filling parameters R2 and R3. And shading reduced starch content and starch-related enzyme activity (including granule-bound starch synthase and soluble starch synthase). Transcriptomic analyses showed that shading mainly affected pathways related to photosynthetic antenna proteins, carbon fixation in photosynthetic organisms, and starch and sucrose metabolism. Sixteen genes related to photosynthetic antenna protein and carbon fixation pathways were first upregulated and then downregulated; whereas all differentially expressed genes (PetC, Fd, LFNR1, LFNR2, PC, PsbO, PsaG, and PSB28) in the photosynthetic antenna protein pathway belonged to electron transport chain proteins. We found that shading treatment affects the physiological and molecular properties of grain development during the grain-filling stage. This study reveals new candidate genes (such as TaLFNR1-7A and TaFd-7A) for breeding wheat varieties with high photosynthetic efficiency in regions with insufficient light intensity.

Climate change, with its increasing temperatures, is significantly disrupting global agricultural systems, and wheat, a key cereal crop faces severe challenges. Heat stress has emerged as a critical threat, accelerating wheat growth, leading to premature maturation, reduced grain filling, and ultimately lower yields. The situation is exacerbated by more frequent and intense heat waves, particularly in regions already struggling with water scarcity. Maintaining the delicate balance of temperature and water necessary for optimal wheat production is becoming challenging, posing a serious risk to global food security. Therefore, there is an urgent need to develop adaptive strategies with innovations in breeding and transgenic technologies crucial to improving wheat resilience to environmental stresses, especially to combat the growing impacts of heat stress. Modern tools like CRISPR/Cas9, Transcription Activator-Like Effector Nucleases, and Zinc Finger Nucleases have been instrumental in developing wheat varieties with improved traits. However, the future of wheat cultivation requires more than just resistance to a single stressor. As climate change intensifies, there is an urgent need for wheat varieties that can withstand multiple stresses, including heat, drought, and pests. Developing these multi-stress-tolerant cultivars is crucial for ensuring food security in a rapidly changing climate.

Wheat grain morphology, particularly grain length (GL) and width (GW), is a key determinant of yield. To improve the suboptimal grain dimensions of the local anthocyanin-rich variety Guizi 1 (GZ1), we crossed it with Zhongyan 96-3 (ZY96-3), an elite germplasm known for faster grain filling and superior grain size. A genotyping-by-sequencing (GBS) approach was applied to an F2 population of 110 individuals derived from GZ1 × ZY96-3, resulting in the identification of 23,134 high-quality SNPs. Most of the SNPs associated with GL and GW were clustered on chromosomes 2B, 3A, and 3B. QTL mapping for GL revealed two major loci, GL1 on chromosome 2B and GL2 on chromosome 3B, and eight candidate genes were identified within their corresponding intervals (2B: 63.6–70.4 Mb; 3B: 631.5–633.3 Mb). These genes encode proteins potentially involved in grain size regulation, including a TOR2 regulation-associated protein, erect spike 2 (EP2), fibroblast growth factor 6 (FGF6), cellulose synthase-like (CSLD), RelA/pot homologue three family protein, and three GDSL esterase/lipase (GLIP) proteins. Additionally, we detected a QTL associated with GW on chromosome 3A and identified two candidate genes, TOR2 regulation and starch synthase within the 61.4–68.5 Mb interval. Overall, this study provides a strong theoretical and technical basis for wheat genetic improvement and offers valuable resources for precise QTL mapping and candidate gene discovery.

Seed priming is an effective seed pretreatment technology that enhances germination and overall crop performance by optimizing seed hydration and metabolic processes before planting. Seed quality is a critical determinant of ... | Find, read and cite all the research you need on Tech Science Press

A ferrugem da folha do trigo (Puccinia triticina Eriks.), importante doença do trigo em todo o mundo, causa graves perdas de rendimento e, portanto, o desenvolvimento de cultivares resistentes é muito importante. Nesta pesquisa, uma linhagem chinesa de trigo (Guinong08-6) mostrou resistência de plantas adultas a uma mistura de isolados do patógeno, , na região de Guiyang, China. Essa linhagem foi cruzada com uma linhagem suscetível de trigo (Guinong19) para desenvolver híbridos F1, F2 e F3. Combinados de marcadores SSR e STS foram usados para mapear genes de resistência à ferrugem da folha em Guinong08-6, e o fenótipo de resistência de Guinong08-6 foi co-regulado por dois genes dominantes complementares, chamados LrGn08-6A e LrGn08-6B. LrGn08-6A foi mapeado para o cromossomo 2AS com marcadores URIC-LN2 e Xgpw2204, que flanquearam o gene em distâncias de 1,8 centimorgano (cM) e 14,83 cM, respectivamente. LrGn08-6B foi mapeado para o cromossomo 4DL com marcadores Xgpw342 e Xbarc93, e ambos flanquearam o gene a uma distância de 26,57 cM. As análises genéticas e moleculares de marcadores demonstraram que LrGn08-6A, que foi herdado de Aegilops ventricosa, pode ser o gene de resistência Lr37, enquanto LrGn08-6B pode ser um gene recentemente descoberto de resistência à ferrugem da folha do trigo.