油菜EST资源的SSR信息分析

从NCBI公共数据库获得63334条油菜EST，通过前处理得到全长为12165.38kb的无冗余EST 17987 条。共在这些序列中搜索出2803个SSR，分布于2443条EST中，出现频率是15.58%。这些EST-SSR的平均长度为18.84bp，平均分布频率是1/4.34kb。二核苷酸重复和三核苷酸重复是主要的类型，二者出现的频率基本相近，占总SSR的近89.05%。AG/CT和AAG/CTT是二、三核苷酸中的优势重复类型，分别占二、三核苷酸重复的84.04%和35.71%，同时对这些SSR的可用性进行了评价。

Analysis of SSR information in EST resource of oilseed rape

63 334 ESTs of oilseed rape in the database of NCBI were downloaded and analysed,resulting in 17 987 non-redundant ESTs with total length about 12 165.38kb.Totally 2 803 SSRs distributed in 2 443 ESTs were detected,accounting for 15.58% of the non-redundant ESTs.The average length and distribution distance of the EST-SSRs were about 18.84 bp and 4.34 kb respectively.Dinucleotide and trinucleotide repeats with similar frequency are the main types,accounting for 89.05% of all the SSRs.AG/CT and AAG/CTT are the most frequent motifs,accounting for 84.04% and 35.71% in dinucleotide and trinucleotide repeats,respectively.The potential of the EST-SSRs for designing primers specific to flanking sequences was assessed.