Pollet N, Mazabraud A
Laboratoire Développement et Evolution, CNRS UMR8080, Université Paris-Sud, Orsay, France.
Genome Dyn. 2006;2:138-153. doi: 10.1159/000095101.
Amphibians have been used since the 19th century as vertebrate models for the experimentalist. Since 50 years or so, Xenopus laevis is the most widely used anuran amphibian research organism. However, because it is a pseudo-tetraploid species, its genetics has been lagging behind. Contemporary studies shift their focus to the only Xenopus species known to be diploid, the small African tropical clawed frog Xenopus tropicalis. A complete genome project is undertaken, with genetic and physical mapping going alongside cDNA and genome sequencing. Currently, X. tropicalis is the most distantly related vertebrate species to humans that still exhibits long-range synteny. Much of amphibian genetics can be learned from this genomic undertaking, and could shed light on fascinating biological processes such as embryogenesis, regeneration and metamorphosis. Moreover, Xenopus species are exciting models for the study of gene duplication because new species can evolve through allopolyploidization, a type of genome duplication that can result from hybridization among species. The current genomic resources for Xenopus briefly described here, combined with the practical experimental advantages of this non-mammalian vertebrate model, make it ideally suited for systematic functional genomic studies.
自19世纪以来，两栖动物就被实验学家用作脊椎动物模型。大约50年来，非洲爪蟾是使用最广泛的无尾两栖类研究生物。然而，由于它是一个假四倍体物种，其遗传学研究一直滞后。当代研究将重点转向已知的唯一二倍体非洲爪蟾物种——非洲热带爪蟾。目前正在开展一个完整的基因组计划，同时进行遗传和物理图谱绘制以及cDNA和基因组测序。目前，非洲热带爪蟾是与人类亲缘关系最远但仍表现出长程同线性的脊椎动物物种。许多两栖动物遗传学知识都可以从这个基因组研究项目中获得，并且可能为胚胎发生、再生和变态等迷人的生物学过程提供线索。此外，非洲爪蟾物种是研究基因重复的令人兴奋的模型，因为新物种可以通过异源多倍体化进化而来，异源多倍体化是一种可能由物种间杂交导致的基因组加倍类型。这里简要描述的非洲爪蟾目前的基因组资源，再加上这种非哺乳动物脊椎动物模型的实际实验优势，使其非常适合进行系统的功能基因组学研究。
