Analysis And Synergetic Matching Of Protein Spot Features In 2D Gel Electrophoresis Images

The extraction of differential protein spots was a key technology of the 2D gel electrophoresis(2DGE) image analysis, and was one of the important research technologies in proteomics, which could provide the basis for disease diagnosis, drug research and analysis of environmental pollution. Moreover, protein spots matching existed as a core step of the extraction of differential protein. Due to the interferences in the generation process, there were complex background in the 2DGE image, which has influenced the precision, stability and reliability of matching algorithms. To solve above problem, this paper made thorough study of analysis and synergetic matching of protein spot features in 2DGE images. The primary research work and achievements are as follows.(1) The base theory about protein spots matching in 2DGE image was detailedly analyzed and systematically studied in this paper. The research work was divided into three parts, features with similarity measures, image distortion and matching strategy.(2) An analysis method based on similarity map was proposed. Firstly, to reduce the influence of interferences such as uneven image background and noise, a filter named BM3 D and an intensifier named CLAHE was implemented. Secondly, the definition and generation methods of similarity map were presented. Thirdly, trait and merits of features such as coordinate similarity, shape-context similarity and morphology similarity were analyzed by similarity map method. Finally, comprehensive utilization of multi-features named product-method was proposed according to analysis results. Many experiments using different 2-DE gel images show that similarity map can be used for intuitional, effective analysis of matching performance intuitively and effectively.(3) An improved image alignment method based on SIFT feature was presented. Firstly, the relative deformations between two 2DGE images were classified, and each cause was analyzed. Secondly, an image align method based on SIFT feature was introduced, and its deficiency was analyzed. Firstly, double threshold and double matching was implemented, to solve the deficiency which can not describe the elastic deformation. Many experiments using different 2-DE gel images show that the improved method can align two 2DGE images more accurately.(4) A synergetic matching method in imitation of human behavior was proposed. Firstly, the decision-making procedures, considerations and criterions were analyzed. Secondly, the matching procedure was divided by spot significance. Finally, different features and strategies were used according to the specific matching step. Many experiments using different 2-DE gel images show that this method can adapt to the complex 2DGE image interferences, which has high precision and strong stability and reliability.