Conservation of long-range synteny and microsynteny between the genomes of two distantly related nematodes
Conservation of long-range synteny and microsynteny between the genomes of two distantly related nematodes
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DOI：
10.1186/gb-2002-3-10-research0057
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发表时间：
2002-01-01
期刊：
影响因子：
12.3
通讯作者：
Blaxter, M. L.
中科院分区：
文献类型：
--
作者：
Guiliano, D. B.;Hall, N.;Blaxter, M. L.
背景：对亲缘关系密切的线虫秀丽隐杆线虫（Caenorhabditis elegans）和布氏秀丽隐杆线虫（Caenorhabditis briggsae）的基因组进行比较，发现重排率很高，且偏向染色体内部事件。为了评估这种模式是否普遍适用于线虫，我们利用基因组序列比较了大约在3亿年前拥有共同祖先的两种线虫物种：模式生物秀丽隐杆线虫和丝虫寄生虫马来丝虫（Brugia malayi）。
结果：对马来丝虫mif - 1基因（巨噬细胞迁移抑制因子，一种人类细胞因子的马来丝虫同源物）侧翼的一个83kb区域进行了测序。与秀丽隐杆线虫的全基因组相比，发现了长程共线性和微共线性保守的证据。在马来丝虫序列中预测的12个蛋白质编码基因中的11个潜在的秀丽隐杆线虫直系同源基因被确定。这些直系同源基因中有10个位于I号染色体上，其中8个聚集在一个2.3Mb的区域。虽然发生了一些相对局部的染色体内重排，但两个各含3个基因的基因簇的顺序、组成和结构是保守的。将马来丝虫细菌人工染色体末端基因组调查序列与秀丽隐杆线虫进行比较，也显示出偏向染色体内重排。
结论：我们认为染色体内重排是驱动线虫染色体组织的主要力量，但受到相邻基因功能元件相互交错的限制。
Background: Comparisons between the genomes of the closely related nematodes Caenorhabditis elegans and Caenorhabditis briggsae reveal high rates of rearrangement, with a bias towards within-chromosome events. To assess whether this pattern is true of nematodes in general, we have used genome sequence to compare two nematode species that last shared a common ancestor approximately 300 million years ago: the model C. elegans and the filarial parasite Brugia malayi.Results: An 83 kb region flanking the gene for Bm-mif-1 (macrophage migration inhibitory factor, a B. malayi homolog of a human cytokine) was sequenced. When compared to the complete genome of C. elegans, evidence for conservation of long-range synteny and microsynteny was found. Potential C. elegans orthologs for 11 of the 12 protein-coding genes predicted in the B. malayi sequence were identified. Ten of these orthologs were located on chromosome I, with eight clustered in a 2.3 Mb region. While several, relatively local, intrachromosomal rearrangements have occurred, the order, composition, and configuration of two gene clusters, each containing three genes, was conserved. Comparison of B. malayi BAC-end genome survey sequence to C. elegans also revealed a bias towards intrachromosome rearrangements.Conclusions: We suggest that intrachromosomal rearrangement is a major force driving chromosomal organization in nematodes, but is constrained by the interdigitation of functional elements of neighboring genes.