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Rosa roxburghii , a calciphilic species native to the mountainous regions of Southwest China, is renowned for its high vitamin C and bioactive components, making it valuable for culinary and medicinal uses. This species exhibits remarkable tolerance to the high-calcium conditions typical of karst terrains. However, the underlying mechanisms of this calcium resilience remain unclear. The Ca 2 + /cation antiporter (CaCA) superfamily plays a vital role in the transport of Ca 2 + and other cations and is crucial for plant tolerance to metal stress. However, the roles and evolutionary significance of the CaCA superfamily members in R. roxburghii remain poorly understood. This study identified 22 CaCA superfamily genes in R. roxburghii , categorized into four subfamilies. The gene structures of these RrCaCAs show considerable conservation across related species. Selection pressure analysis revealed that all RrCaCAs are subject to purifying selection. The promoter regions of these genes contain numerous hormone-responsive and stress-related elements. qRT-PCR analyses demonstrated that H + /cation exchanger (CAX) RrCAX1a and RrCAX3a were highly responsive to Ca 2 + stress, cation/Ca 2 + exchanger (CCX) RrCCX4 to Mg 2 + stress, and RrCCX11a to Na + stress. Subcellular localization indicated that RrCAX1a is localized to the plant cell membrane, and its stable transformation in tobacco confirmed its ability to confer enhanced resistance to heavy Ca 2 + stresses, highlighting its crucial role in the high-calcium tolerance mechanisms of R. roxburghii . This research establishes a foundation for further molecular-level functional analyses of the adaptation mechanisms of R. roxburghii to high-calcium environments.

Phospholipase C (PLC) is an essential enzyme involved in lipid signaling pathways crucial for regulating plant growth and responding to environmental stress. In sorghum, 11 PLC genes have been identified, comprising 6 PI-PLCs and 5 NPCs . Through phylogenetic and interspecies collinearity analyses, structural similarities between SbPLCs and ZmPLCs proteins have been observed, with a particularly strong collinearity between SbPLCs and OsPLCs. Promoter function analysis has shown that SbPLCs are significantly enriched under abiotic stress and hormonal stimuli, like ABA, jasmonic acid, drought, high temperature, and salt. Gene co-expression networks, constructed using a weighted gene co-expression network analysis (WGCNA), highlight distinct expression patterns of SbPLC1 , SbPLC3a , and SbPLC4 in response to abiotic stress, providing further insights into the expression patterns and interactions of SbPLCs under various environmental stimuli. qRT-PCR results reveal variations in expression levels among most SbPLCs members under different stress conditions (drought, NaCl, NaHCO 3 ), hormone treatments (ABA), and developmental stages, indicating both specific and overlapping expression patterns. This comprehensive analysis offers valuable insights into the roles of SbPLCs in sorghum, shedding light on their specific expression patterns, regulatory elements, and protein interactions across different environmental stimuli and developmental stages.

Cadmium (Cd) is a toxic heavy metal that accumulates in plants, negatively affecting their physiological processes, growth, and development, and poses a threat to human health through the food chain. 6-phosphogluconolactonase (PGL) is a key enzyme in the Oxidative Pentose Phosphate Pathway(OPPP) in plant cells, essential for cellular metabolism. The OPPP pathway provides energy and raw materials for organisms and is involved in antioxidant reactions, lipid metabolism, and DNA synthesis. This study describes the Cd responsive gene AetPGL from Aegilops tauschii. Overexpression of AetPGL under Cd stress increased main root length and germination rate in Arabidopsis . Transgenic lines showed higher antioxidant enzyme activities and lower malondialdehyde (MDA) content compared to the wild type. The transgenic Arabidopsis accumulated more Cd in the aboveground part but not in the underground part. Expression levels of AtHMA3 , AtNRAMP5 , and AtZIP1 in the roots of transgenic plants increased under Cd stress, suggesting AetPGL may enhance Cd transport from root to shoot. Transcriptome analysis revealed enrichment of differentially expressed genes (DEGs) in the plant hormone signal transduction pathway in AetPGL -overexpressing plants. Brassinosteroids (BR), Gibbenellin acid (GA), and Jasmonic acid (JA) contents significantly increased after Cd treatment. These results indicate that AetPGL may enhance Arabidopsis ' tolerance to Cd by modulating plant hormone content. In conclusion, AetPGL plays a critical role in improving cadmium tolerance and accumulation and mitigating oxidative stress by regulating plant hormones, providing insights into the molecular mechanisms of plant Cd tolerance.

Trisomy harbouring an extra copy of the chromosome generally causes a variety of physical and intellectual disabilities in mammals but is an extremely rare and important genetic stock in plants. In this study, a spontaneous trisomy plant in a Chinese kale accession ( Brassica oleracea var. alboglabra , CC, 2 n = 18) that showed significantly smaller plant architecture when compared to other normal plants was found and subsequently confirmed by cytological analysis in which the chromosome set of 2 n = 19 and abnormal chromosome behaviour were observed. Then, based on the gene expression deviation determined by RNA-seq, the extra chromosome copy in this trisomy was identified as chromosome C2 (TC2). Compared to normal plants, TC2 not only showed generally upregulated differentially expressed genes (DEGs) on chromosome C2 (97.21% of 573 DEGs in chromosome C2) but also exhibited a whole-genome expression perturbation, in which 1329 DEGs (69.87% of total DEGs) were observed along two-copy chromosomes ( trans -effect). The genes in the high (gene expression value > 100) and medium (100 > gene expression value > 10) groups were more prone to decreased gene expression, but the genes in the low group (10 > gene expression value > 0.1) showed upregulated expression deviation. In addition, GO (Gene ontology) annotation analysis revealed that the upregulated DEGs in the trans -effect group were overrepresented by the genes involved in the response to stress category, while the downregulated DEGs in the trans -effect group were mostly enriched in pathways related to DNA synthesis. In conclusion, we think our results can provide important resources for genetic analysis in B. oleracea and show some novel insights for understanding trisomy plant biology.