Molecular Definition Of Filarial & Nonfilarial Genes

利用EST（表达序列标签）的方法，我们已经能够确定超过965个基因簇的班氏丝虫基于1687 EST。有趣的是，令人惊讶的是，这些成簇的EST中有很高的百分比（584/965; 60%）含有推定的信号肽，只有6个似乎是GPI锚定的。当与马来丝虫（Bm）mf EST/簇相比时，45%的Wb簇与Bm EST匹配（同一性范围为86-100%），而较少（22%）的Wb簇与盘尾丝虫（Ov）mf EST匹配（同一性范围为80-100%）。 对粪类圆线虫采取了类似的方法，从两个独立的生命周期阶段进行了>10000个EST。将该寄生线虫与自由生活的C. elegans已经完成;数据表明寄生和非寄生线虫之间基因表达的巨大差异（Mitreva，DM，McCarter，JP. Marin，J，Dante，M，Wylie，T，Chipelli，B，Pape，D，克利夫顿，SW. Nutman，TB，Waterston，RH.寄生线虫和自由生活线虫Strongyloides stercoralis和秀丽隐杆线虫基因表达的比较基因组学。Genome Res 14：209-220，2004）。

Using an EST (expressed sequence tag) approach, we have been able to identify greater than 965 gene clusters from Wuchereria bancrofti microfilariae based on1687 ESTs. Interestingly, a surprisingly high percentage (584/965; 60%) of these clustered ESTs contain a putative signal peptide, and only 6 appear to be GPI anchored. When compared to Brugia malayi (Bm) mf ESTs/Clusters, 45% of the Wb clusters had matches to Bm ESTs (identities ranging from 86-100%) whereas fewer (22%) matched Onchocerca volvulus (Ov) mf ESTs (with identities ranging from 80-100%). A similar approach has been taken with Strongyloides stercoralis with >10000 ESTs being done from two separate lifecylcle stages. Comparisons between this parasitic nematode and the free-living C. elegans has been perfomed; the data demonstrate the vast differences in gene expresssion between parasitic and non-parasitic nematodes (Mitreva, DM, McCarter, JP. Marin, J, Dante, M, Wylie, T, Chipelli, B, Pape, D, Clifton, SW. Nutman, TB, Waterston, RH. Comparative Genomics of Gene Expression in the Parasitic and Free-living Nematodes Strongyloides stercoralis and Caenorhabditis elegans. Genome Res 14: 209-220, 2004).