Study On Effect Of Sound On Differential Expression Genes In Chrysanthemum

Much work has been done about some environment stresses such as drought, water flow, salinity and mechanical stimulation inducing the differential expression of genes in plant. However, Reports about the study of the effects of the sound, a widespread environment stress, on the gene expression of plants are rare. Only the preliminary study showed that heredity substance had no variation under sound stimulation, but gene expression was altered. However, it is still unclear which gene fragments in the plant are differentially expressed under sound stimulation. In this thesis, chrysanthemum is chosen as. test material and the differential expression of chrysanthemum genes are preliminarily studied to screen out genes induced by the sound wave.Firstly, the total RNA of chrysanthemum is extracted. The chrysanthemum seedling is treated by sound wave with a certain intensity (100dB) and frequency (1000 Hz) for 60 minutes a day, After 9 days, the total RNA of the treated group and the control group are extracted with RNase Plant Mini kit. The results show that high-quality total RNA has been obtained. The concentration, the purity and the integrality of the total RNA can satisfy the need of the subsequent tests. Moreover, the yield rate of total RNA is larger in the treated group than in the control group(Tab 4.1).As a template, the total RNA extracted from the treated group and the control group is reversely transcribed into cDNA. mRNA reverse transcription differential display PCR(DDRT-PCR) is applied to screen out the differential expression gene fragments induced by the sound wave. 8 pieces of bands, which are SA5-1, SA5-2, SA7, CA7, SCI, SC8-1, SC8-2, CGI respectively, are isolated by the polypropylene acyl gel electrophoresis(Fig 5.7, 5.8). After being re-amplified, only the 3 bands, which are SA5-2, SCI and SC8-1, appear on the agarose gel(Fig 5.9). The molecular weight of the three gene fragments on the agarose gel and on the polypropylene acyl gel is approximate. They are the fragments that are looked for.Northern dot hybridization is used to further confirm whether SA5-2, SCI and SC8-1 are the differential expression gene induced by the sound wave or not. The results demonstrate that SA5-2 and SC8-1 are really the differential expression genes, whose molecular weight are 290bp and 270bp respectively. Thereinto, SA5-2 is dominantly expressed, and SC8-1 is differentially expressed, while SCI is fake positivefragment(Fig 5.10,5.11,5.12). SA5-2 and SC8-1 are goning to be cloned and sequenced, and then their functions further analyzed.By analyzing the differential gene fragments in the chrysanthemum and in the Arabidopsis thaliana, it is found that SA5-2 in the chrysanthemum and SA3 in the Arabidopsis thaliana are very similar(Fig 5.13,5.14), which are amplified from primer combination with the same anchored primer: AAG CTT TTT TTT TTA and the similar random primer. The sequence of random primer is AAGCTTAGTAGGC and AAGCTTTGGTCGA respectively. In addition, the molecular weight of SA5-2 and SA3 is also very approximate. The two gene fragments will be further analyzed in the succedent tests.