Evolution of the eukaryotic membrane-trafficking system: origin, tempo and mode
Evolution of the eukaryotic membrane-trafficking system: origin, tempo and mode
复制标题
DOI：
10.1242/jcs.013250
复制
发表时间：
2007-09-01
影响因子：
4
通讯作者：
Field, Mark C.
中科院分区：
文献类型：
--
作者：
Dacks, Joel B.;Field, Mark C.
膜系统的出现是原核生物向真核生物进化过渡的关键阶段。最近的基因组和分子进化分析提供了对这个关键系统如何达到其现代结构的见解。与线粒体、质体和细胞核的情况相比，内膜机制的原核前体明显相对缺乏。总的来说，证据表明真核生物膜运输机制的自生起源。早期真核生物的祖先有一个复杂的内膜系统，这意味着这个细胞系统在原真核生物与其他原核生物分道扬镳后进化得相对较快。贩运系统的许多组成部分是基因复制的结果，这些复制产生了功能相似但亚细胞位置不同的蛋白质。因此，具有非常简单的运输系统的原真核生物可能通过编码细胞器身份的蛋白质的同源基因家族扩展，在最后的真核共同祖先（LCEA）中进化到接近现代的复杂性。这一共同祖先的后代经历了贩运机制的进一步修改；单细胞的简单性和多细胞的复杂性是主流趋势，但也有一些显著的反例。
The emergence of an endomembrane system was a crucial stage in the prokaryote-to-eukaryote evolutionary transition. Recent genomic and molecular evolutionary analyses have provided insight into how this critical system arrived at its modern configuration. The apparent relative absence of prokaryotic antecedents for the endomembrane machinery contrasts with the situation for mitochondria, plastids and the nucleus. Overall, the evidence suggests an autogenous origin for the eukaryotic membrane-trafficking machinery. The emerging picture is that early eukaryotic ancestors had a complex endomembrane system, which implies that this cellular system evolved relatively rapidly after the proto-eukaryote diverged away from the other prokaryotic lines. Many of the components of the trafficking system are the result of gene duplications that have produced proteins that have similar functions but differ in their subcellular location. A proto-eukaryote possessing a very simple trafficking system could thus have evolved to near modern complexity in the last common eukaryotic ancestor (LCEA) via paralogous gene family expansion of the proteins encoding organelle identity. The descendents of this common ancestor have undergone further modification of the trafficking machinery; unicellular simplicity and multicellular complexity are the prevailing trend, but there are some remarkable counter-examples.