The Cloning And Initial Function Analysis Of IAA Related Gene In Eggplant(Solanum Melongena L.)

IAA plays an important role in promoting cell growth, fruit development, as well as inparthenocarpic fruit development. Thus, cloning parthenocarpic IAA-related genes and studying itsmechanism of action have important implications for the molecular mechanism of in-depth study ofparthenocarpic fruit development and guidance parthenocarpic varieties breeding. This research basis onSSH library between parthenocarpic eggplant line ‘D-10’ and non-parthenocarpic eggplant line ‘03-2’.The purpose is to analyze the differences in the expression pattern of IAA-related gene sequences. Afterit, RACE is used for the cloning of IAA-related gene and then the vector for RNAi and VIGS should beestablished to study the function of this gene. The main results were summed as follows:1. Based on analysis of SSH library between parthenocarpic eggplant and non-parthenocarpiceggplant, there are4IAA-related ESTs(Z47、Z732、F1134、F1312) are found. qRT-PCR is used to studythe expression pattern of these ESTs in parthenocarpic eggplant and non-parthenocarpic eggplant. TheReal-time PCR results showed that the expression regulation of the4ESTs is different in each variety.And the expression level of Z732in parthenocarpy is significantly higher than in non-parthenocarpicovary.2. CDNA sequence of gene SmIAA19is obtained by RT-PCR and RACE from parthenocarpiceggplant. The length of SmIAA19is800bp, including a558bp ORF, which encodes185amino acids.The gene is close to potatoes in the evolutionary tree, and on the same branch with tomatoes. Result ofqRT-PCR indicates that SmIAA19gene is expressed in ovary and fruit of eggplant parthenocarpy andnon-parthenocarpy, and the expression in parthenocarpy is significantly higher than non-parthenocarpy.The highest expression is found at anthesis day in parthenocarpic ovaries. SmIAA19expression quantitykeeps in low level in the non-parthenocarpy strain neither the condition of low temperature nor theoptimum temperature. So this research shows that SmIAA19gene may be associated with the eggplantparthenocarpy.3. An RNAi vector has been constructed to silence SmIAA19gene by homologous recombinationcloning (Gateway). A length of416bp of cDNA is selected to construct the RNAi vector for SmIAA19.As soon as the vector is completed, detection should be conducted by microbial PCR, sequencing,digestion and so on. At last the RNAi vector should be transformed into Agrobacterium, it lays thefoundation for further validating the role of this gene in the parthenocarpic eggplant.4. On the basis of SmAGPP gene has been cloned in the laboratory, VIGS vector has been finishedand the text that infects the vector into leaves has been completed. Silencing effect was analyzed byquantitative phenotypes and qRT-PCR. Comparing with the control group, it shows no obviousphenotypical difference in silence plant but gene expression is fall down.