Establishing Virus Induced Gene Silence Technique in Africa Violet (Gesneriaceae)
| Autor: | Yu-Wen Kuo, 郭宇文 |
|---|---|
| Rok vydání: | 2008 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 96 African violet (Saintpaulia ionantha) is perennial Gesneriaceae plants. Its flowers show two different type of symmetry: zygomorphy (wild type) and actinomorphy (perolic type) types. In precious studies on gene expression pattern for flower symmetry, we found CYC(CYCLOIDEA) gene is a candidate in controlling flower development for zygomorphy. However, its function and phenotypic effect have never been investigated. The aim of this study is therefore to establish a VIGS system in African violet. With VIGS system, we can further explore the function of floral symmetry gene such as CYC. To establish the system, we start by using SiPDS (Saintpaulia ionantha phytoene desaturase) as a reporter gene and then flower symmetric SiCYC (Saintpaulia ionantha cycloidea) as our interest gene. We use two virus vectors, CymMV (cymbidium mosaic virus) and TRV (tobacco rattle virus), produce three constructs: pCymMV-SiPDS、pTRV2-SiCYC and pTRV2-SiPDS. TRV vector was transformed into agrobacterium for infection. In order to compare the efficiency of different Agrobacterium strains, we transformed pCambia-3130 into GV3101, GV2260 and LBA4404 three different agrobacterium strains. And use GUS as a reporter gene to detect the efficiency of different agrobacterium strains. The result shows that 2 day post infecttion with three strains of agrobacterium carrying GUSintron-pCambia-3130, there was no GUS activity in leaves. This may due to the low infection rate of agrobacterium to Africa plantlet, and our limited sample size. 1 month after infect with TRV and CymMV virus vector, there was no silencing phenotypes. When using RT-PCR detect CymMV virus RNA, no CymMV virus RNA was detected in the plant. TRV infection also failed to induce VIGS. However, surprisingly we found artificial TRV2 sequence in both infected and non-infected plants. But there was no TRV1 detectable in the plants. Since the detected TRV2 was different from our construct, and TRV2 can not move without TRV1, the TRV2 sequence may have already inserted into plant genome before our experiment, and cause the failure of our infection. In the future works, it should be cautious to confirm non-TRV2 insertion strain for establishing African violet VIGS system. No TRV2 insert primitive Africa violet may be the proper material for investigation. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|