Inducing The Silence Of γ-tubulin Gene In Nicotiana Tabacum With Potato Virus X Vector

γ-tubulin is a importance unit of microtubule organization center, dispersed in cytoplasm,nucleolus and all microtubule arrays, γ-tubulin also play a vital role in microtubule nucleation, cell cycle and the formation of spindle. For the disruption of y-tubulin causing the young plant death, it bring some diffcults in exploring its functions.In our experiments, the recombination PVX vectors, including the different fragment of y-tubulin cDNA, were used to induce the endogenesis y-tubulin mRNA degradation. And the special phenotyes were expected for studying the functions of γ-tubulin.The vectors of PVX-D and PVX-E were selected for inoculation tobaccos. After 14 days of post inoculation, the mosaic disease spots were appeared in leaves. After 2 months of post inoculation, the small-narrow and sunken-brink leaves were found. During the tobacco development, more special phenotypes such as the alternation of small-narrow and sunken-brink leaves, stem branching in the region of root and apex and the sterile tobaccos also found in tobaccos. Using some methods such as SEM, IF and Real－time PCR, all the phenotypes of that tobaccos were seperately study in the tissue,cell and transcription levels. The results showed that the mRNA of γ-tubulin in tobacco leave were successfully knock-down by VIGS, the lower mRNA of γ-tubulin in tobacco leave cells caused the cells of sporgy parenchyma more bigger and the loss-small cell and the lower chloroplast in palisade parenchyma; the cytoskeleton and the distribution of chloroplast in guard cells were changed; the nulear membrane diffused and nucleus became smaller; the activation of pollen of tobaccos degraded. All facts demonstrated that the lower expression of the y-tubulin in tobacco had severity impact on the development of tobacco and its leaves.