Mitochondrial Genome Comparison Research Of Soybean Cytoplasmic Male Sterility On RNA Level

Soybean, originated in China, is an important kind of plant source of protein and edible oil. Since 1923, researchers in China has cultivated more than 1,000 kinds of soybean breeds by tridational breeding methods, which plays an important role in the promotion of soybean production, and greatly satisfies consumer demands. However, since 1995, China has began to import soybeans, and by 2006 the imports had rised to 2827 million tons, accounting for two thirds of the domestic soybean market. Chinese soybean can not meet growing domestic demand, mainly because of the low soybean production. The average level of soybean production is not only lower than the three-top soybean producing States- United States, Brazil and Argentina, but also lower than the world's average. Therefore, it is quite urgent to search for new soybean resourse with high yield.Cytoplasmic male sterility (cytoplasmic male sterility, CMS) is a natural phenomenon, widely existed in higher plants. It is maternal genetic, with sterial pollen but normal pistil. The sterility Can be restored by nuclear restore gene. The breeding work can be more easier by the use of CMS plants, because there is no need to cut the pollen and it will save much labor and money. Thus the male sterial line is widely used in the world. Heterosis has been successfully utilized in rice, corn and other major crops, but no soybeans, because of the lack of perfect male sterial line. Our study is to discover the mechanism of cytoplasmic male sterility and find out infertility-related genes in soybeans, in order to cultivate soybean male sterial line, that will make great improvement in soybean production in China.All life activities in cells need energy, which comes from nutrients in the body by a series of oxidation-reduction reactions. Each mole of glucose molecules can relese about 690,000 cards energy. But the cell can not immediately consume so much energy, it stores up most of the energy by the form of available free energy. Mitochondria, the primary venue of respiration, lacks of an effective system of mismatch repair. So mitochondrial genome, compared with nuclear genome, has a higher variability. Once this mutation leads to abnormal mitochondrial function, affecting cell respiration, will play an adverse effect on cells. Therefore, I chose 7 mitochondrial genes, encoding key proteins in respiratory chain, as probe to conduct northern blot experiment among male sterile line, maintainer line and F1 generation, expecting to find out CMS relative genes and then finally make clear the mechanism of soybean infertility, in order to improve the yield of soybean.In this experiment, the plant materials are sterial line(JLCMS1A), maintainer line(JLCMS1B) and F1 generation of soybean. I chose 7 mitochondrial genes in soybean as probe to make northern blot analysis among the above three materials.The main results are as follows:1. There are no differances between the three lines on the analysis of atpA,coxI,coxIII,cob and coxI.2. The content of longer copy of atp6 in CMS line and F1 line is much more than the maintainer line.3. The length of nad9 gene in maintainer line is shorter than CMS line and F1 line.