| Summary: | 碩士 === 國立臺灣大學 === 農藝學研究所 === 87 === Transgenic rice (Oryza sativa L. TNG67) plants overexpressed HVA22 gene were studied. Four plasmids were constructed as follows: (1) pYAVH: ABRC1/Amy 6-4 promoter::HVA22 gene and 35S promoter::hpt (hygromycin phosphotransferase) gene (2) pCAVGH: ABRC1/Amy6-4 promoter::HVA22 gene , 35S promoter::hpt gene and 35S promoter::GUS. (3) pSAVGH: 35S promoter::HVA22 gene ,35S promoter::hpt gene and 35S promoter::GUS gene. (4) at-pSAVGH: 35S promoter::antisense HVA22 gene, 35S promoter::hpt gene and 35S promoter::GUS gene
The regeneration frequenies of rice plants transformed with four plasmids were 5.3%, 2.8%, 2.8% and 1.1% respectively.The plasmid containing the inducible promoter(ABRC1/Amy 6-4 promoter) has a higher transformed persontage.
PCR amplification was used to exam the existense of transgene integration. It was observed that there are 4 plants in YAV-III have no HVA22 gene amplification sequence. This suggests that different transgenic plants can be obtained with HVA22 gene or not be obtained with HVA22 gene in a transgenic line.
The Southern blot analysis showed that HVA22 gene inserted into the rice genome successfully, and with the copy number from 3 to 10 in each transformant.
The Northern blot analysis showed that all transformants express HVA22 mRNA in different level.
In vegetative growth stage, the transgeinc rice plants with ABA inducible promoter showed normal growth. However, the plants with 35S constitutive promoter showed less tiller and lower seed-set percentage. The plant transformed with antisense HVA22 was inhibited concerning the plant height and flowering time. These results suggest that the growth of rice plants can be affected by overexpression of HVA22 gene or antisense HVA22 gene.
|
|---|
