Rabinowicz Pablo D, Bennetzen Jeffrey L
The Institute for Genomic Research, 9712 Medical Center Drive, Rockville, Maryland 20850, USA.
Curr Opin Plant Biol. 2006 Apr;9(2):149-56. doi: 10.1016/j.pbi.2006.01.015. Epub 2006 Feb 3.
The genomes of flowering plants vary in size from about 0.1 to over 100 gigabase pairs (Gbp), mostly because of polyploidy and variation in the abundance of repetitive elements in intergenic regions. High-quality sequences of the relatively small genomes of Arabidopsis (0.14 Gbp) and rice (0.4 Gbp) have now been largely completed. The sequencing of plant genomes that have a more representative size (the mean for flowering plant genomes is 5.6 Gbp) has been seen as a daunting task, partly because of their size and partly because of the numerous highly conserved repeats. Nevertheless, creative strategies and powerful new tools have been generated recently in the plant genetics community, so that sequencing large plant genomes is now a realistic possibility. Maize (2.4-2.7 Gbp) will be the first gigabase-size plant genome to be sequenced using these novel approaches. Pilot studies on maize indicate that the new gene-enrichment, gene-finishing and gene-orientation technologies are efficient, robust and comprehensive. These strategies will succeed in sequencing the gene-space of large genome plants, and in locating all of these genes and adjacent sequences on the genetic and physical maps.
开花植物的基因组大小从约0.1千兆碱基对（Gbp）到超过100 Gbp不等，这主要是由于多倍体以及基因间区域重复元件丰度的差异。拟南芥（0.14 Gbp）和水稻（0.4 Gbp）相对较小基因组的高质量序列目前已基本完成。对具有更具代表性大小（开花植物基因组的平均值为5.6 Gbp）的植物基因组进行测序一直被视为一项艰巨的任务，部分原因在于其基因组大小，部分原因在于存在众多高度保守的重复序列。然而，植物遗传学领域最近已经产生了创新性策略和强大的新工具，因此现在对大型植物基因组进行测序已成为现实可能。玉米（2.4 - 2.7 Gbp）将是首个使用这些新方法进行测序的千兆碱基规模的植物基因组。对玉米的初步研究表明，新的基因富集、基因完成和基因定向技术高效、稳健且全面。这些策略将成功地对大型基因组植物的基因空间进行测序，并将所有这些基因及相邻序列定位到遗传图谱和物理图谱上。
