The Analysis Of Bt Transgenic Rice Pollen Fertility And Storage Protein Under Temperature Treatment

Plant transgenic engineering technology provides a advanced, efficient and safe way for the resist of rice pest to ensure the sustainable rice yields. This research attempts to analyze the ecological adaptability of transgenic Bt rice seed setting ratio and seed storage protein quality in order to explain the decrease of transgenic Bt rice seed setting ratio as well as the impact on seed storage protein quality with the expression of Bt gene and provide a important basis for the application of transgenic rice production.Minghui63(Oryza sativa L.), T1C-19 and 2A-1 were selected as the experimental materials in this study. Minghui63, T1C-19 and 2A-1 with Bt gene(cry1C* and cry2A*) are near isogenic lines which are provided by Professor Lin Yongjun. On conditions of 22 ℃, 33 ℃and natural temperature the indexes of pollen viability, fertility and germinability combined with seed setting ratio were detected in order to understand Bt gene in transgenic rice yield potential impact on the ecological adaptability. Also, the treatments of 22 ℃, 33 and natural temperature during ℃ rice filling stage was setted to analyze the protein contents and components, especially the Glutelin and its subunits.The main obtained results are as follows:1. The fertility of Minghui63, T1C-19 and 2A-1 have no significant difference on conditions of different temperature. But the pollen viability of T1C-19 was decreased at 33 ℃ compared to MH63, while the pollen viability of 2A-1 had no significant difference.The germinability of MH63 and 2A-1 were 3.9% and 4.9% at 33 ℃ treatment which had a higher level than T1C-19 that was consistent with the result of pollen viability. According to the seed setting ratio, T1c-19 had difference on seed setting ratio especially at 33 ℃ treatment.2. The crude protein under temperature treatment(33℃ and 22℃) were lower and the content of low temperature reduced more, but there was no significant difference between Minghui63, T1C-19 and 2A-1 under the same conditions. According to the SDS-PAGE with the SSPs components of the step extraction, the content of transgenic rice 2A-1 and T1C-19 grain soluble protein(Albumin and Globulin) increased, while Prolamin and Glutelin reduced. The transgenic rice grain protein composition changed while Albumin and Globulin protein of T1C-19 increased under low temperature and the Prolamin content of 2A-1 T1C-19 fell under high temperature. Especially under 33℃ treatment, on one hand the contents of pro-glutelin(57 k D) of MH63 was improved, on the other hand the contents of pro-glutelin(57 k D) of Bt transgenic rices both were improved separately showing that the composition and accumulation of SSPs transformed on high temperature stress.While the polymerization is attributable to disulfide bond formation. In the subsequent amino acid analysis, especially cysteine content of T1C-19 increased by 67% and 43% than MH63 at normal and 33℃ temperature.3. According to the result of Glu A subunit in the immunoblotting, the pro-glutelin of Glu A-1 subunit had no significant differnce during varities at 33 ℃, but the α-glutelin of T1C-19 and 2A-1 had a lower level than MH63; while the Glu A-2 and Glu A-3 subunit had a specific expression with 90 k Da polymer. The expression of Glu B-1 and Glu B-2 subunit had no significant difference during temperatures and varities indicating consistency and stability; according to the Western Blot of Glu B-4 and Glu B-5 subunit, the expression of 90 k Da polymer of T1C-19 and 2A-1 had a significantly higher level than MH63 at 33 ℃ and 22℃ as well as the gray value of of 90 k Da polymer 2A-1 had a significantly higher level than MH63.The indexes of pollen germinability, fertility and viability germinability indicates Bt transgenic rice has little difference under normal temperature with MH63 but under temperature treatment. There has no difference between composition of SSPs in rice grain, but the the specific expression of Glu B-4 and Glu B-5 subunit. Thess findings will enrich the knowledge of grain protein deposition under high-temperature stress at the molecular level and provide a potential temperature-response indicator to assess the grain quality.