分析EST寻找小鼠胸腺基质细胞表达基因

网上生物信息量的膨胀导致新基因寻找手段的改变，借助mRNA差异显示技术获得的17个表达序列标签（EST），通过对美国国家生物技术信息中心（NCBI）的非冗余序列库（NT）和小鼠EST库的BLAST同源检索，发现有4个序列与已知基因高度同源，其中的HDPs和Eps8两个基因是首次在小鼠胸腺基质细胞中发现，它们可能与T细胞在胸腺内的发育分化有关，其它EST则为新基因，本结果也为下一步新基因的克隆及功能研究提供了有益的线索。

Identification of the genes expressed in mouse thymus stromal cells by EST analysis

Ever expanding bioinformatic resources has led to a revolutionary change in the strategies for identifying and cloning novel genes. After obtaining 17 piece of cDNA fragments by mRNA differentially display from mouse thymus stromal cells , the authors used them to screen the Non redundant GenBank of National Center for Biotechnology Information (NCBI) and mouse EST database (http://ncbi.nlm.nih.gov/) respectively by Blast program. The Blast similarity search showed that about 76% of the analyzed ESTs had no homology with the known genes ,although half of them overlapped with some submitted ESTs,only 4 ESTs represented known genes,they were Eps8(mouse),Hsp65(mouse),cytochrome oxidase I(mouse) and DHPs(human),Northern blot hybridization further confirmed the conclusion. This is the first time the DHPs and Eps8 gene were identified in mouse thymus stromal cells. Their expression in thymus implied they might play a role in the T cells development.