Rujan T, Martin W
Institute of Botany III, Universität Düsseldorf, Universitätsstr. 1, D-40225 Düsseldorf, Germany.
Trends Genet. 2001 Mar;17(3):113-20. doi: 10.1016/s0168-9525(00)02209-5.
It is well known that chloroplasts and mitochondria donated many genes to nuclear chromosomes during evolution - but how many is "many"? A sample of 3961 Arabidopsis nuclear protein-coding genes was compared with the complete set of proteins from yeast and 17 reference prokaryotic genomes, including one cyanobacterium (the lineage from which plastids arose). The analysis of 386 phylogenetic trees distilled from these data suggests that between approximately 400 (1.6%) and approximately 2200 (9.2%) of Arabidopsis nuclear genes stem from cyanobacteria. The degree of conservation preserved in protein sequences in addition to lateral gene transfer between free-living prokaryotes pose substantial challenges to genome phylogenetics.
众所周知，叶绿体和线粒体在进化过程中向核染色体捐赠了许多基因——但“许多”具体是多少呢？将3961个拟南芥核蛋白编码基因的样本与酵母的完整蛋白质组以及17个参考原核生物基因组进行了比较，其中包括一种蓝细菌（质体起源的谱系）。对从这些数据中提取的386个系统发育树的分析表明，拟南芥核基因中约400个（1.6%）至约2200个（9.2%）起源于蓝细菌。除了自由生活的原核生物之间的横向基因转移外，蛋白质序列中保留的保守程度对基因组系统发育学构成了重大挑战。
