生物谷报道：利什曼原虫可以引起广泛的临床疾病。最近，科研人员报道了对两种利什曼原虫的基因组测序：婴儿利什曼原虫和巴西利什曼原虫。这一研究结果发表在最新一期的《自然－遗传学》杂志上。
科研人员将这两种新测序的利什曼原虫基因组与已报道的硕大利什曼原虫基因组进行了比较，发现三者之间存在显著的保守性，仅有约200个基因存在微分分布的差异。但是，与已报道的利什曼原虫基因组不同的是，在巴西利什曼原虫的基因组中存在RNA干扰通路组件、端粒连接转座元件和逆转座子。此外，研究人员还发现，假基因的形成和基因丢失是造成不同利什曼原虫基因组差异的主要原因。这些在不同利什曼原虫基因组上分布不同的基因编码的蛋白质，在宿主与病原体的相互作用，以及寄生虫在巨噬细胞中生存等生理活动中具有重要作用。这些基因可能是研发疫苗的良好候选者，它们也可能对于发现利什曼原虫如何躲避免疫系统有帮助，而且它们还能让科学家更有效地预测疫苗是否成功。
Figure 1 - Chromosome 32 of L. major showing the positions of genes with a differential distribution between the three Leishmania species analyzed.
The organization of chromosome 32 is shown schematically; both strands containing long, non-overlapping gene clusters2. Genes that are restricted to only one or two of the three Leishmania species are not concentrated in the subtelomeric regions or at the breakpoint between polycistronic transcription units, as seen in other kinetoplastid parasites5, but are distributed more evenly along the chromosome. Most gene differences are a result of pseudogene formation rather than insertion or deletion of new sequences.
原文出处：
Nature Genetics 39, 839 - 847 (2007)
Published online: 17 June 2007 | doi:10.1038/ng2053
Comparative genomic analysis of three Leishmania species that cause diverse human disease - pp839 - 847
Christopher S Peacock, Kathy Seeger, David Harris, Lee Murphy, Jeronimo C Ruiz, Michael A Quail, Nick Peters, Ellen Adlem, Adrian Tivey, Martin Aslett, Arnaud Kerhornou, Alasdair Ivens, Audrey Fraser, Marie-Adele Rajandream, Tim Carver, Halina Norbertczak, Tracey Chillingworth, Zahra Hance, Kay Jagels, Sharon Moule, Doug Ormond, Simon Rutter, Rob Squares, Sally Whitehead, Ester Rabbinowitsch, Claire Arrowsmith, Brian White, Scott Thurston, Frédéric Bringaud, Sandra L Baldauf, Adam Faulconbridge, Daniel Jeffares, Daniel P Depledge, Samuel O Oyola, James D Hilley, Loislene O Brito, Luiz R O Tosi, Barclay Barrell, Angela K Cruz, Jeremy C Mottram, Deborah F Smith & Matthew Berriman
doi:10.1038/ng2053
Abstract - Comparative genomic analysis of three : Leishmania: species that cause diverse human disease | Full Text - Comparative genomic analysis of three Leishmania species that cause diverse human disease | PDF (721 KB) - Comparative genomic analysis of three Leishmania species that cause diverse human disease | Supplementary information
