期刊
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
卷 112, 期 51, 页码 15690-15695出版社
NATL ACAD SCIENCES
DOI: 10.1073/pnas.1514974112
关键词
gene cost; transcription; translation; cellular bioenergetics; evolutionary genomics
资金
- Multidisciplinary University Research Initiative Awards [W911NF-09-1-0444, W911NF-14-1-0411]
- US Army Research Office
- National Institutes of Health [R01-GM036827]
- National Science Foundation [MCB-1050161, CNS-0521433]
An enduring mystery of evolutionary genomics concerns the mechanisms responsible for lineage-specific expansions of genome size in eukaryotes, especially in multicellular species. One idea is that all excess DNA is mutationally hazardous, but weakly enough so that genome-size expansion passively emerges in species experiencing relatively low efficiency of selection owing to small effective population sizes. Another idea is that substantial gene additions were impossible without the energetic boost provided by the colonizing mitochondrion in the eukaryotic lineage. Contrary to this latter view, analysis of cellular energetics and genomics data from a wide variety of species indicates that, relative to the lifetime ATP requirements of a cell, the costs of a gene at the DNA, RNA, and protein levels decline with cell volume in both bacteria and eukaryotes. Moreover, these costs are usually sufficiently large to be perceived by natural selection in bacterial populations, but not in eukaryotes experiencing high levels of random genetic drift. Thus, for scaling reasons that are not yet understood, by virtue of their large size alone, eukaryotic cells are subject to a broader set of opportunities for the colonization of novel genes manifesting weakly advantageous or even transiently disadvantageous phenotypic effects. These results indicate that the origin of the mitochondrion was not a prerequisite for genome-size expansion.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据