Cloning And Characterization Of The Growth And Resistance Peanut Gene And Study Their Expression

Peanut is one of the important oil and economic crops worldwide, ranking the fourth important oildcrop globally. The yield,qualities,disease and adversity defenses of peanut are important production problems which have long been affecting the sustainable development of peanut dormain. However, these characters are resulted from the composite regulations of internal genes under certain environments, especially closely associated with seed gene itself. In order to known the mechanism underneath the growth and development of peanut seed, our laboratory have constructed a mix full-length cDNA library of developing seed, and have carried out library screening, sequencing and bioinformatics analysis. Six genes relating to seed development and defenses were chosen for further study based on the work done, aiming to characterize the expressions in different tissues and stages as well as associating with abiotics stresses. The roles of in participating signal pathway was also predicted using bioinformatics methods.1.Using semi-quantitative RT-PCR, the expression levels of CEM1, LEA gene, ACRE19-like gene, GAPDH, PDH-E1ACPHA were analysed in different stages of peanut pericarp, testa, kernel (10d, 20d, 30d, 40d, 50d, 60 day after pegging) , and the results showed that amplified bands of CEM1 is brighter in pericarp; two LEA genes all express in pericarp, testa, kernel with no same patterns; ACRE19-like gene express more in pericarp; GAPDH gene shows its expression in pericarp, testa, kernel, but the expression level is not high; PDH-E1ACPHA gene expresses in pericarp, testa, kernel weakly, with 10d and 60d of pericarp, 60d of testa and 40d and 50d of kernel expressed a litter higher。2. The expression levels of CEM1, LEA genes, ACRE19-like gene, GAPDH and PDH-E1ACPHA gene in different organs (root, stem, leaf, flower,gynophores and pod ) of peanut were also carried using semi-quantitative RT-PCR. CEM1gene only express in gynophores and pod, LEA-3D10 gene expressed in root, stem , leaf, flower and gynophores, but LEA-5H23 gene expressed main in pods. ACRE19-like gene almost not expressed in root and leaf, but higher in flower and gynophores, GAPDH gene and PDH-E1ACPHA gene expressed in all organs of not so high.3. Semi-quantitative RT-PCR was employed to analysis the expression levels of LEA genes, ACRE19-like gene under stresses of abiotics treatments. Two LEA genes under various stresses exhibited different expression patterns, ACRE19-like gene expressed high in all abiotics stresses with higher expression level in low temperature and drought, changing expression levels with time after stresses with SA, ABA and ethylene.4. Using Bioinformatics analysis the molecular weight, isoelectric point, hydrophobicity, signal peptide and so on, we predicted that CEM1 was related to the development of peanut pericarp, and that ACRE19-like genes might have something to do with multi-signal trasduction pathway regulated by the peanuts and LEA to do with drought-resistance of peanuts. Besides, GAPDH and PDH-E1ACPHA might have an important regulation role in maintaining the stability in metabolism of peanut mass and energy, which provided a foundation for the study and identification of function in peanut genes. which is some helpful for the further research in peanut .So far, the studies on molecular biology in peanut are still weak in comparison with other equiponderance crops but are carried out much quicker than before.The results obtained in the paper would increase our understanding of the area which would supply with guidance for peanut production.