Expression Research And Function Analysis Of SlMYBL Gene In Tomato

In the process of plant growth and development, there are many kind ofparticipation and regulation of transcription factors, MYB transcription factor, is the oneof the more important plant transcription factors, and it constitutes one of the largestfamily of transcription factors in plant. This kind of family of transcription factors hasthe common features, is in its n-terminal contains about52amino acid residues, and theamino acid residues formed MYB domain structure, and the structure of MYB domainis highly conservative. MYB proteins in plants according to the number of MYBdomain repetitive sequence can be divided into three types: contains two MYBrepetitive sequence of R2R3MYB, contains three adjacent MYB repetitive sequenceR1R2R3-MYB and some other usually contains only a MYB repetitive sequence ofspecific groups collectively called MYB-like protein. MYB transcription factor familyin plants, mainly involved in plant growth and metabolism of cells, but the part is alsoinvolved in plant response to external art, when plant is outside bad conditions, such ashigh temperature, damage, the abiotic stress such as drought, signal will continue toinspire the stress related expression of transcription factors. And these transcriptionfactors will interact with their corresponding cis element, then start the expression ofspecific genes, so plants will appear a series of physiological and biochemical reaction,which changes the resistance of plants against the outside environment. MYBtranscription factors in plants is one of the important family of transcription factors, andthe class of transcription factors are closely related to the resistance of plants, itsresearch mainly concentrated in the model plant, such as arabidopsis and rice. However, so far, the tomato MYB genes in the process of abiotic stress related researchis less, qRT-PCR technique was used to study stress under the condition of tomatoMYB class gene expression patterns are also reported. And tomato as an importantvegetable crops, the plant’s ability to fight outside bad environment is a kind ofimportant agronomic characters, thus the MYB family genes involved in tomato onmolecular mechanism of plant stress response is necessary. This study based on NCBIdatabase login sequence of tomato, the cloning size of1350bp gene and the ORF of1245bp, encoding414amino acids. Expression pattern analysis shows that SlMYBL inmature leaves, stems, and sepals in higher quantity. Using fluorescence quantitativePCR analysis showed that SlMYBL genes in exogenous hormones IAA, MeJa and ABAtreatment to express quantity increase. Abiotic stress results show that in the hightemperature, low temperature, damage and salt, the gene expression induced bydifferent degrees. This research is mainly to obtain the following results:1、According to the NCBI database login sequence of tomato, and design specificprimers, cloning from the wild type tomato AC++and get length of1350bp genefragment.2、bioinformatics analysis, SlMYBL protein has a conservative dna-binding domain:MYB-like, C-end and multiple phosphorylation sites, mainly located in themitochondrial matrix and in the cytoplasm, the protein secondary structure prediction is26.33%of alpha helix,1.93%of the beta fold,6.28%of the extension chain,65.46%ofthe random curl. And with a number of known plant MYB protein sequence alignmentsimilarity high up to70%.3、In wild type tomatoes and mutant Nr, rin organizations，the SlMYBL genesexpression pattern analysis found: the SlMYBL genes express in higher quantity in thewild type (WT) in young leaves, mature leaves and old leaves,；Expression is less inroots, stems and sepals. In Nr mutants IMG to B+4did not change significantlyexpression of fruit, but the mutant rin relative strengthening of various periods of fruitexpression.4、fluorescence quantitative PCR analysis of exogenous hormones on SlMYBL geneexpression: wild type tomato plants found in exogenous hormone treatment, SlMYBLgene by IAA, ABA, MeJa and hormones GA3induced.5、abiotic stress on SlMYBL gene expression: the high and low temperatureprocessing tomato plant SlMYBL after gene expression. Salt after processing SlMYBLgene expression is characterized by raised, but more sensitive than the root. To induceSlMYBL gene expression after injury treatment, but the genetic slower response toinjury.6、build the pBI121-SlMYBL super expression vector and pBIN19-SlMYBL silentcarrier, and by agrobacterium mediated method will exceed expression vector and silentcarrier success into tomato AC++cotyledon explant, and received multiple tomatotransgenic strains.7、transgenic tomato strains under simulated drought conditions, over-expressionstrain compared with wild type strain more healthy plant growth status, silence and thewild type strain poor plant growth condition. Under the condition of the dehydrationenvironment, over-expression strain dehydration rate than wild type strain is slow.