Project description:The degree of yellowing in tobacco leaves is an important indicator for determining the maturity and harvesting time of tobacco leaves. Reduction in chlorophyll is of utility for promoting the concentrated maturation of tobacco leaves and achieving mechanised harvesting and mining, and utilising tobacco yellow leaf regulatory genes is of great significance for the selection and breeding of tobacco varieties suitable for mechanised harvesting and the resolution of the molecular mechanisms controlling leaf colouration. In this study, the phenotypes of the yellow-leaf K326 and K326 varieties were analysed, and it was observed that the yellow-leaf K326 variety exhibited a distinct yellow leaf phenotype with a significant reduction in chlorophyll content. Subsequently, using a combination of BSA-seq, transcriptomic sequencing (RNA-seq), and proteomic sequencing approaches, we identified the candidate gene Nitab4.5_0008674g0010 that encodes dihydroneopterin aldolase as a factor associated with tobacco leaf yellowing. Finally, by measuring the folate content in K326 and Huangye K326, the folate content in Huangye K326 was observed to be significantly lower than that in K326, thus indicating that folate synthesis plays a crucial role in phenotypic changes in tobacco yellow leaves. This study is the first to use BSA-seq combined with RNA-seq and proteomic sequencing to identify candidate genes in tobacco yellow leaves. The results provide a theoretical basis for the analysis of the mechanism of tobacco yellow leaf mutations.
2024-10-23 | GSE270039 | GEO
Project description:Composition of interleaf bacteria in tobacco leaves with different disease severity and healthy tobacco leaves
Project description:Comparative analysis of tobacco leaves transcriptomes unveils carotenoid pathway potentially determined the characteristics of aroma compounds in different environmental regions. Tobacco (Nicotiana tabacum) is a sensitive crop to environmental changes, and a tobacco with unique volatile aroma fractions always formed in specific ecological conditions. In order to investigate the differential expressed genes caused by environmental changes and reveal the formation mechanism of characteristics of tobacco in three different aroma tobacco regions of Guizhou Province, Agilent tobacco microarray was adapted for transcriptome comparison of tobacco leaves in medium aroma tobacco region Kaiyang and light aroma tobacco regions Weining and Tianzhu. Results showed that there was big difference among the gene expression profiles of tobacco leaves in different environmental conditions. A total of 517 differential expressed genes (DEGs) between Weining and Tianzhu were identified, while 733 and 1,005 genes differentially expressed between Longgang and another two tobacco regions Weining and Tianzhu, respectively. Compared with Longgang, up-regulated genes in Weining and Tianzhu were likely involved in secondary metabolism pathways, especially carotenoid pathway, including PHYTOENE SYNTHASE, PHYTOENE DEHYDROGENASE, LYCOPENE ε-CYCLASE, CAROTENOID β-HYDROXYLASE and CAROTENOID CLEAVAGE DIOXYGENASE 1 genes, while most down-regulated genes played important roles in response to temperature and light radiation, such as heat shock proteins. Gene Ontology and MapMan analyses demonstrated that the DEGs among different environmental regions were significantly enriched in light reaction of photosystem II, response of stimulus and secondary metabolism, suggesting they played crucial roles in environmental adaptation and accumulation of aroma compounds in tobacco plants. Through comprehensive transcriptome comparison, we not only identified several stress response genes in tobacco leaves from different environmental regions but also highlighted the importance of carotenoid pathway genes for characteristics of aroma compounds in specific growing regions. Our study primarily laid the foundation for further understanding the molecular mechanism of environmental adaptation of tobacco plants and molecular regulation of aroma substances in tobacco leaves.
Project description:Tobacco (Nicotiana tabacum L.) is an important cash crop, and the size of its leaves significantly influences both yield and quality. However, the upper part of tobacco leaves, due to its dense tissue structure, often faces issues such as narrow and thick leaves during the production of roasted cigarettes. These problems have a severe impact on the yield and quality of the upper leaf. Although the mechanism of leaf size regulation in Arabidopsis thaliana has been extensively studied, it remains unclear for tobacco. Therefore, this research aimed to investigate the role of the NtAN3 gene in regulating tobacco leaf size by utilizing the NC82 variety. The researchers created both an overexpression mutant (G27) and a silencing mutant (M21) of the NtAN3 gene and examined their impact on leaf size using cell morphology observation and transcriptome analysis. These research findings offer valuable insights for molecular breeding aimed at improving tobacco yield and enhancing the availability of upper leaves.