Development Of Est-Derived SSR Markers And Construction Of Digital Northern Platform For Apple

Apple (Malus Mill.) has become a worldwide important economic crops, this is not only of great variety, widely distributed, and cultivation has a long history. In fruit cultivation, breeding and ornamental plant research and application, etc is very high economic value. Therefore, as this is precious plant, the germplasm resources research has an important meaning, has become an important research fruit trees commercial characteristic of one of the model plant.EST-SSR is developed in recent years of the new molecular marker. EST can indirect gain gene function information, and the building of a small fragment genomic library for microsatellite sequences than screening, from EST database for microsatellite sequences to economic, simple and rapid, with EST-SSR construction of genetic linkage map, positioning function known gene, which will direct identification decided to important phenotypic allele, is the rapid identification of the genome is simple but effective way. Usually EST sequence conservative degree is higher, EST mark in the family and genus of the universality between than from non expression sequence of mark higher, that is to say it more generality. Development suitable for the apple EST-SSR markers for study of the origin of apple germplasm resources evolution and genetic relationship and genetic diversity is of great significance.In the NCBI dbEST database included the rich apple EST sequence information resources,2010as of December12, GenBank published the article63708apple EST sequence. This study analysis the apple in EST SSR loci distribution rule, the development of apple EST-SSR primer, to explore the EST-SSR used for apple varieties genetic differences the feasibility of the research.1. All the63,708EST sequences of apple were obtained from NCBI. Simple sequence repeats (SSRs) of apple expressed sequence tags (EST) in public database were investigated by using computer program MISA (microsatellite).The results showed that6153SSRs were identified from the5423apple EST sequences founded from the all of63708apple ESTs. The dinucleotide, trinucleotide and hexanucleotide repeats were the dominant types with the frequency of50.38%,14.85%and15.47%, respectively.2. These sequences were screened by using MIS A software to search for SSR motifs.49pairs of primers were designed by the software Primer5.0Plus.The PCR products of these primers were detected by PAGE.Summary of its characteristics,,and some of them were recovered for sequencing. Gel analysis showed that33amplified distinct bands and expected products, and25were polymorphic. The dendrogram showed that it was consistent with Fuji apple family relationship. And the other related to its affinity. Apple EST-SSR markers development efficiency is higher, the apple varieties of appraisal and analysis of genetic diversity has important application value.3. The objective of the study is to take full advantage of mass expression sequence tags (ESTs) from NCBI database, establish localization digital platform for apple genes, and achieve the purpose of rapid large-scale gene expression analysis. ESTs were downloaded from GenBank, processed further by bioinformatics methods, and used to build the digital Northern platform. The apple gene digital Northern platform can provide a useful analysis tool for rapid large-scale analysis of the apple gene expression and mining of the related important data.