Characterization and Mapping of a Novel Premature Leaf Senescence Mutant in Common Tobacco (Nicotiana tabacum L.)

Abstract

As the last stage of plant development, leaf senescence has a great impact on plant’s life cycle. Genetic manipulation of leaf senescence has been used as an efficient approach in improving the yield and quality of crop plants. Here we describe an ethyl methane sulfonate (EMS) mutagenesis induced premature leaf senescence mutant yellow leaf 1 (yl1) in common tobacco (Nicotiana tabacum L.). The yl1 plants displayed early leaf yellowing. Physiological parameters and marker genes expression indicated that the yl1 phenotype was caused by premature leaf senescence. Genetic analyses indicated that the yl1 phenotype was controlled by a single recessive gene that was subsequently mapped to a specific interval of tobacco linkage group 11 using simple sequence repeat (SSR) markers. Exogenous plant hormone treatments of leaves showed that the yl1 mutant was more sensitive to ethylene and jasmonic acid than the wild type. No similar tobacco premature leaf senescence mutants have been reported. This study laid a foundation for finding the gene controlling the mutation phenotype and revealing the molecular regulation mechanism of tobacco leaf senescence in the next stage.

Analysis of Physiological and Transcriptomic Differences between a Premature Senescence Mutant (GSm) and Its Wild-Type in Common Wheat (Triticum aestivum L.)

“…Endogenous levels of abscisic acid (ABA) in the rice premature senescence mutant psl85 increase considerably in the late stage of aging, indicating that psl85 takes part in ABA-induced leaf senescence [ 22 ]. Compared with WT, the tobacco leaf senescence mutant yl1 shows higher mones [ 23 ]. An auxin-auxotrophic mutant of tobacco, IVA3 , shows premature death [ 24 ].…”

Transcriptome divergence between developmental senescence and premature senescence in Nicotiana tabacum L.

“…Gene_22548(UNE10) and gene_58303(SPL5) belonged to the significantly expressed transcription factor, gene_38513(EIN3) and gene_26067(ABF2) were enriched in ethylene and ABA signal transduction pathway, gene_14104(At5g53970), gene_20929(UMK3), gene_36428(HSP90) and gene_82898(ACLB-1) were the key DEGs due to PPI analysis. Gene_34964(SAG12) and gene_35004(RBCS) were regarded as the senescence-associated genes 46,47 . Most of the transcript levels detected by qRT-PCR showed the similar patterns with the gene expression levels obtained from RNA-Seq (Supplementary Table S5, Supplementary Figure S2), and the accordance of transcriptome sequencing and qRT-PCR results were confirmed by a high correlation coefficient (R 2 ) of 0.8753 ( Fig.…”

iTRAQ-based quantitative proteomic of tobacco (Nicotiana tabacum L.) identified major host proteins involved in photosystems throughout the aging process

“…In addition, up-regulated proteins were also involved in metabolic pathways such as "Protein processing in endoplasmic reticulum" (8), "Tyrosine metabolism" (7), "Phenylpropanoid biosynthesis" (6), "ABC transporters" (5) and "Plant-pathogen interaction" (5) and "Isoquinoline alkaloid biosynthesis" (5). Down-regulation of protein involves in "Photosynthesis" (26), "Carbon fixation in photosynthetic organisms" (18), "Glycolysis/glycogenesis" (11), "Ribosome" (8), "Oxidative phosphorylation" (7), "Pentose phosphate pathway" (7) and so on ( Fig. 5A).…”