Department of Biology, College of Charleston, Charleston, SC 29401, USA.
Trends Plant Sci. 2012 Apr;17(4):204-12. doi: 10.1016/j.tplants.2012.01.006. Epub 2012 Feb 9.
Arabidopsis thaliana is now a model system, not just for plant biology but also for comparative genomics. The completion of the sequences of two closely related species, Arabidopsis lyrata and Brassica rapa, is complemented by genomic comparisons among A. thaliana accessions and mutation accumulation lines. Together these genomic data document the birth of new genes via gene duplication, transposon exaptation and de novo formation of new genes from noncoding sequence. Most novel loci exhibit low expression, and are undergoing pseudogenization or subfunctionalization. Comparatively, A. thaliana has lost large amounts of sequence through deletion, particularly of transposable elements. Intraspecific genomic variation indicates high rates of deletion mutations and deletion polymorphisms across accessions, shedding light on the history of Arabidopsis genome architecture.
拟南芥现在不仅是植物生物学的模式系统，也是比较基因组学的模式系统。两个密切相关的物种拟南芥 lyrata 和油菜的序列完成后，通过对拟南芥品系和突变积累系的基因组比较进行了补充。这些基因组数据共同记录了通过基因复制、转座子适应和从头从非编码序列形成新基因而产生的新基因的诞生。大多数新基因座的表达水平较低，并且正在经历假基因化或亚功能化。相比之下，拟南芥通过缺失，特别是转座子的缺失，失去了大量的序列。种内基因组变异表明，在不同品系中存在高频率的缺失突变和缺失多态性，这为研究拟南芥基因组结构的历史提供了线索。
