Plant Biotechnology Journal最新文献

High temperature has posed significant challenges to global agriculture, markedly leading to reduced fertility and yield losses in tomato (Solanum lycopersicum). Therefore, thermotolerance-conferring genes and loci are needed to further improve cultivated tomatoes. Here we identified an E3 ubiquitin ligase SlRNF185, containing a C3HC4-type RING-HC domain, that confers tomato pollen thermotolerance. As a predominant ubiquitination member, SlRNF185 could degrade the SlVPS29 protein induced by heat stress to enhance thermotolerance. Mechanistically, we found that a heat shock transcription factor SlHSFA7 dramatically activates the expression of SlRNF185 under heat stress and acts as a positive regulator of tomato pollen thermotolerance. Collectively, our findings reveal that a SlHSFA7-SlRNF185 genetic module regulates ubiquitination-mediated degradation of SlVPS29 under heat stress, providing the strategy for breeding thermotolerance tomato varieties.

Amino acids serve as fundamental building blocks and signalling molecules in plants, orchestrating stress adaptation mechanisms against diverse biotic and abiotic environmental challenges. However, the mechanism by which plants alter their nutrient metabolism processes to coordinate nitrogen use efficiency (NUE) and salt tolerance remains elusive. Here, we identified a Lysine-Histidine-type transporter 5 (LHT5) gene through genome-wide association studies (GWAS) that enhances NUE via amino acid accumulation regulation. Further research showed that OsLHT5 also confers salt tolerance in rice by promoting proline biosynthesis through transcriptional upregulation of OsP5CS1 and OsP5CS2 genes, thereby increasing cellular proline levels for osmotic adjustment. Notably, we identified a functionally critical 30-bp deletion in the OsLHT5 coding region, designated as the elite haplotype LHT5^HapA, which substantially enhances amino acid transport capacity and consequently improves both NUE and salt tolerance. Functional validation demonstrated that overexpression of LHT5^HapA significantly increases amino acid content, nitrogen accumulation, grain yield and salt stress tolerance compared to the wildtype allele. This study establishes a novel molecular framework linking amino acid transport to the coordination of nutrient utilisation and stress tolerance, offering valuable genetic resources and breeding strategies for developing climate-resilient rice cultivars with enhanced productivity under both optimal and saline conditions.

Promoter engineering holds immense potential for fine-tuning gene expression and optimising agronomic traits, yet conventional genome-editing tools face limitations in precision, scalability, and risk mitigation. Here, we develop Prime Editing-mediated Promoter Engineering (PEPE), a DSB-free platform integrating bidirectional Protospacer adjacent motif (PAM) recognition (NGG/CCN) with combinatorial duo-pegRNA strategies to achieve tiled, overlapping deletions across entire plant promoters. Applying PEPE to the 1.8-kb rice D53 promoter, we generated a mutant library with stepwise deletions. Edited alleles showed stable inheritance, and dual-method validation confirmed the precision at junctions. Quantitative profiling revealed functional modularity: core-region deletions suppressed D53 expression by 70%-85%, while a distal deletion (D53-G9C10) paradoxically upregulated transcription 2.2-fold, uncovering a cryptic repressor element. Phenotypic variation corresponded with transcriptional changes, establishing a direct link between cis-regulatory diversity and agronomic traits. By circumventing DSBs and enabling kilobase-scale CRE manipulation, PEPE establishes a robust framework for decoding promoter logic and accelerating trait pyramiding in crops. This study advances plant genome editing by merging precision with scalability, offering transformative potential for breeding climate-resilient, high-yield cultivars.

The main genetic diversity observed in cultivated citrus results from a reticulate evolution involving four ancestral taxa whose radiation occurred in allopatry. In such context, GWAS analysis, genome diversity and transcriptomic studies will be significantly enhanced through pangenome approaches. We report the implementation of a super-pangenome for cultivated citrus, established with de novo assemblies of C. medica, C. reticulata and C. micrantha, released for the first time alongside a published chromosome-scale assembly of C. maxima. Repetitive element annotation revealed that half of each genome consisted of transposable elements or DNA-satellites. The new genome assemblies display strong synteny and collinearity, while discrepancies are observed with the C. maxima assembly. Resequencing information from 55 accessions helped to explore the intra- and interspecific diversity of the ancestral taxa and their relationships with horticultural groups. Diagnostic SNPs of the ancestral taxa revealed interspecific introgressions in several representative accessions of C. reticulata, C. maxima and C. medica as well as insights into the origin and phylogenomic structures of horticultural groups. PAV analysis revealed a gene whose absence or presence was specific to one of the ancestral taxa. Diagnostic PAV analysis uncovered a large chloroplastic introgression in C. medica chromosome 4. The analysis of the functional enrichment and species-specific adaptations in the citrus super-pangenome revealed distinct functional specialisations. This highlights the evolutionary paths that have shaped species, contributing to the diversity in the citrus super-pangenome while maintaining a shared foundation of essential biological processes. We established a Genome Hub, offering a platform for continuous genomic research.