Woods I G, Kelly P D, Chu F, Ngo-Hazelett P, Yan Y L, Huang H, Postlethwait J H, Talbot W S
Department of Developmental Biology, Stanford University School of Medicine, Stanford, California 94305, USA.
Genome Res. 2000 Dec;10(12):1903-14. doi: 10.1101/gr.10.12.1903.
Zebrafish mutations define the functions of hundreds of essential genes in the vertebrate genome. To accelerate the molecular analysis of zebrafish mutations and to facilitate comparisons among the genomes of zebrafish and other vertebrates, we used a homozygous diploid meiotic mapping panel to localize polymorphisms in 691 previously unmapped genes and expressed sequence tags (ESTs). Together with earlier efforts, this work raises the total number of markers scored in the mapping panel to 2119, including 1503 genes and ESTs and 616 previously characterized simple-sequence length polymorphisms. Sequence analysis of zebrafish genes mapped in this study and in prior work identified putative human orthologs for 804 zebrafish genes and ESTs. Map comparisons revealed 139 new conserved syntenies, in which two or more genes are on the same chromosome in zebrafish and human. Although some conserved syntenies are quite large, there were changes in gene order within conserved groups, apparently reflecting the relatively frequent occurrence of inversions and other intrachromosomal rearrangements since the divergence of teleost and tetrapod ancestors. Comparative mapping also shows that there is not a one-to-one correspondence between zebrafish and human chromosomes. Mapping of duplicate gene pairs identified segments of 20 linkage groups that may have arisen during a genome duplication that occurred early in the evolution of teleosts after the divergence of teleost and mammalian ancestors. This comparative map will accelerate the molecular analysis of zebrafish mutations and enhance the understanding of the evolution of the vertebrate genome.
斑马鱼突变定义了脊椎动物基因组中数百个必需基因的功能。为了加速对斑马鱼突变的分子分析，并便于比较斑马鱼与其他脊椎动物的基因组，我们使用了一个纯合二倍体减数分裂定位面板来定位691个先前未定位基因和表达序列标签（EST）中的多态性。连同早期的工作，这项研究使定位面板中计分的标记总数增加到2119个，包括1503个基因和EST以及616个先前已鉴定的简单序列长度多态性。对本研究及先前工作中定位的斑马鱼基因进行序列分析，确定了804个斑马鱼基因和EST的推定人类直系同源基因。图谱比较揭示了139个新的保守同线性，其中两个或更多基因在斑马鱼和人类的同一条染色体上。尽管一些保守同线性相当大，但保守组内基因顺序发生了变化，这显然反映出硬骨鱼和四足动物祖先分化后，倒位和其他染色体内重排相对频繁发生。比较图谱还表明，斑马鱼和人类染色体之间不存在一一对应关系。对重复基因对的定位确定了20个连锁群的片段，这些片段可能是在硬骨鱼和哺乳动物祖先分化后硬骨鱼进化早期发生的一次基因组复制过程中产生的。这一比较图谱将加速对斑马鱼突变的分子分析，并增进对脊椎动物基因组进化的理解。
