| China is a major country for plant oil consuming and importing. Rape is the main oil-bearing crop considering its growing areas and developing speed. In addition, Rape heterosis is becoming wide accept way to research the molecular mechanism of genic male sterility. In this study, based on the results of gene expression in Brassica napus double-dominat cytoplasm male sterile line by microarrays, we select six genes, GAPC and AT2G36580 are related to glucose metabolism, LACS9 and ACAT2 are involved in fatty acid metabolism, PABP and LTP12 are anther specific genes. Our purpose is to clarify the molecular mechanism of genic male sterility of Brassica napus. So we decide to explore all the chosen genes'expression model in roots, stems, leaves, flowers, pods, pistils and stamens by realtime PCR. Bn_PABP was cloned and sequenced, then gene structure and function were analysed by bioinformatics software. In all, we expect to understand the molecular mechanism of Brassica napus genic male sterility. The results as follows:1. In glucose metabolism, GAPC and AT2G36580 were expressed in all organizations. in fertile buds They exhibit the highest expression level at the stage of tetrad to uninucleate, which are 5.06 and 1.69 times compared to that at the meiosis stage. Furthermore, GAPC and AT2G36580 in fertile line stamen had a higher expression levels Nearly 9.11 and 4.47 fold than in sterile line pistils.2. In fatty acid metabolism, LACS9 and ACAT2 were highly expressed in pods. They were strong expressed in fertile buds, uninucleate stage, which are 3.28 times and 1.39 times respectively higher than that at the meiosis stage. However, they were significantly lower expressed in sterile buds. Further analysis of LACS9 and ACAT2 in stamens and pistils showed that expression level in fertile line stamens were 2.03 and 3.43 fold higher than that in sterile line pistils.3. PABP and LTP12 are anther specific genes. That is to say, both of them were highest expressed in flowers especially at the stage of tetrad to uninucleate in fertile buds But they were obviously lower expressed in sterile buds. Analysis of PABP and LTP12 in stamens and pistils showed that expression levels in fertile line stamens were 6.78 and 9.45 fold higher compared to that in pistils of sterile line.4. Analysis of gene expression profile indicated that all six gene expression patterns have some identities, such as the expression level of fertile buds raised up from the stage of tetrad to uninucleate and declined at the trinucleate stage, while they were significantly lower expressed in sterile buds from tetrad to uninucleate stage. Further analysis of these genes in stamens and pistils suggest that all of them were highly expressed in fertile line stamens and less expressed in sterile line stamens. All the results verify that these genes are related to genic male sterility , although they belong to different types of metabolic pathway. It would be worthwhile to study more detail to identify their functions.5. Bn_PABP gene was analysed by bioinformation and molecular methods, total length of DNA sequences has been cloned and translated. It encods 651 amino acids, which molecular weight was 71598.4, and isoelectric point was 8.38. Bn_PABP has a high similarity with PABP5 in PABP family of Arabidopsis thaliana because Brassica Napus and Arabidopsis are phylogentically very close related. The homology of protein was 76%. Comparing these genes structures by Clone Manager 5, we found they had similar structure which had four RNA recognize motifs and a PABP superfamily motif. Simulation of three-dimension showed that they were highly similitude in function locations.
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