Tobacco Mutant Databases

The Tobacco Mutant Database (TobaccoMDB) maintains a database of mutant data for the model higher plant tobacco. Data available from TobaccoMDB includes the EMS, T-DNA mutants and related information.

Project description

Nicotiana tabacum L. belongs to the Solanaceae family, which contains many agriculturally important species such as tomato, potato, eggplant, and pepper. Tobacco is an important cash crop and dicotyledonous model plant for research. Recently, the draft genomes of Nicotiana tabacum and Nicotiana sylvestris and Nicotiana tomentosiformis were assembled. Nicotiana tabacum is an amphiploid species (2n=48) likely resulting from an interspecific cross between N. sylvestris (2n=24) and N. tomentosiformis (2n=24). Futhermore, a high-resolution genetic linkage map, physical maps, and completed genome sequence for tobacco will be available.

The goal of this project (funded by This work was financially supported by China Tobacco Genome Project [110201101009(JY-03), 110201201004(JY-04), 110201301005(JY-05)]) is to add to the growing collection of genomic resources available for tobacco by creating large collections of T-DNA lines and EMS-mutagenic lines. These resources can therefore serve to identify mutations in genes predicted to affect agronomic characteristics of Solanaceae and other plants. Mutant lines are publicly available through this site, allowing any interested researchers to identify knockouts or activation in specific genes of interest.

TobaccoMDB resource details

Activation tagging was used to generate approximately 100,000 transgenic tobacco plants. Southern blot analysis indicated that there were 1.6 T-DNA inserts per line on average in our transformed population. The phenotypes observed include abnormalities in leaf and flower morphology, plant height, flowering time, branching, and fertility. Among 6,000 plants in the T0 generaton, 57 displayed visible phenotypes. Among 4,105 lines in the T1 generation, 311 displayed visible phenotypes. Fusion primer and nested integrated PCR (FPNI-PCR) was used to identify 963 independent genomic loci of T-DNA insertion sites (ISs) in 1,257 T1 lines. The distribution of T-DNA insertions was non-uniform and correlated well with the predicted gene density along each chromosome. The insertions were biased toward genic regions and noncoding regions within 5 kb of a gene. Fifteen plants that showed the same phenotype as their parent with a dominant pattern in the T2 generation were chosen randomly to detect the expression levels of genes adjacent to the T-DNA integration sites by semi-quantitative RT-PCR (sqRT-PCR). Fifteen candidate genes were identified. Activation was observed in 7 out of the 15 adjacent genes, including one that was located 13.1 kb away from the enhancer sequence. The activation-tagged population described in here will be a highly valuable resource for tobacco functional genomics research using both forward and reverse genetic approaches.

A new tobacco mutant population induced by ethyl methane sulfonate mutagen was developed for functional genomics applications. 94,997 M2 family lines and 14,189 derived high-generation lines were generated from the donor of ZY100. We isolated 1,607 mutant lines and 8,610 mutant plants with altered morphological phenotypes from 5,513 independent M2 families that consisted of 69,531 M2 plants. The 2,196 phenotypic categories in the M2 putative mutants were classified into four groups with 17 major categories and 51 subcategories. Verification of the phenotypes in high generations indicated that 70.63% of the M3 lines, 84.87% of the M4 lines, and 95.75% of the M5 lines could perfectly transmit pre-mutations of the corresponding M2, M3, and M4 mutant plants. Along with the increased generation of mutants, the ratios of lines inheriting pre-mutations increased and lines with emerging neo-mutations decreased. Genetic analyses of 18 stably heritable mutants showed that two mutants were double recessive, five were monogenic recessive, eight presented monogenic dominant inheritance and two presented semi-dominant inheritance. All of the phenotyping data, mutant images and seeds were registered in "TobaccoMDB" database.