Characterization And Analysis Of The Genes Functioning In Tobacco Mutants Of Abnormally Branching

The study on the tobacco gene function is of great importance to the plant biology. Environmentaland genetic factors regulating plant development branch,Multi-gene and complicated mechanismaffecting the branch development.At present, the mechanism of tobacco regulation branch developmentis not clear, nor seen the related research of branch development about tobacco. Flanking sequencesobtained by FPNI. In this study, abnormal branching tobacco constructed by T-DNA activation tagging.Analysis and determine the insertion site and the genes by bioinformatics. Determine the gene whichcause of mutations. The main results were as follows:(1)A survey on the phenotypes was made over the T2, T3 population.And multiple alignmentswere made on the flanking sequences of T2, T3 lines. According to the genes by insertion locilocalization and blast for homologous proteins, the T-DNA insertion loci were localized. A genotypingto identify homozygous individual was also conducted for the 11 lines, the T2, T3 population wasgenotype segregated. And search the genes for the insertion site about near 100 k upstream anddownstream, to determine gene mutations cause abnormal branching belong to B3 superfamily.(2)ARF is subfamily of B3 superfamily. A total of 50 ARF genes were identified from tobaccowith complex genetic structures contained 10 exons generally. The prediction of subcellular localizationshowed that a few of ARF proteins harbored mitochondrial or chloroplast localization sequences. Themajority of ARF proteins were not found located signals. All members of the ARF genes were assignedto 22 chromosome. The analysis of expression pattern showed that the ARF genes had differentexpression patterns and tissue specificity.(3)The gene of B3 superfamily in tobacco not found. The study selected tomato a close relativeof tobacco. A totall of 97 B3 genes were confirmed in the tomato genome. All the members weredivided into four subfamilies, including LAV, ARF, RAV and REM, with 4, 22, 9 and 62 members,respectively. The branch of each subfamily was obviously distinguished from others in the phylogenetictree, with analyzing the function domains of all members. All members of the B3 superfamily wereassigned to each chromosome, and each subfamily distributed in different patterns and frequency. Theexpression patterns of 11 B3 superfamily members indicated that even the members in the samesubfamily had different spatial and temporal expression profiles. When treated by drought, NaCl, andhigh temperature, each member responded to different stress signals, and some respondings wereintense and significant. However, the response to ABA treatment was very weak.( 4) A total of 98 LBD genes were identified from tobacco with simple genetic structurescontained 1-3 exons generally. Tobacco LBD gene family be divided into two types(I and II). All LBDmembers had conserved domain CX2CX6CX3 C, however, the type II genes had secondary structure ofcoiled coil made of LX6LX3LX6 L. Furthermore, LBD genes can be divided into 5 sub families(Ia, Ib,Ic, Id and II) by their phylogenetic relationship with Arabidopsis. 36 members have EST evidenc; theanalysis of EST, array data and transcriptome show that the LBD genes had different expression patternsand tissue specificity.