Stability and evolution of overlapping genes
Stability and evolution of overlapping genes
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DOI：
10.1111/j.0014-3820.2000.tb00075.x
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发表时间：
2000-06-01
期刊：
影响因子：
3.3
通讯作者：
Krakauer, DC
中科院分区：
文献类型：
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作者：
Krakauer, DC
当相同的核苷酸序列编码一个以上功能多肽的区域时，该序列包含重叠基因。重叠在快速进化的基因组中最常见，具有高突变率，如病毒，细菌和线粒体。重叠被认为是重要的，因为：（1）将最大量的信息压缩到结构基因的短序列中的手段;以及（2）作为通过功能相关多肽的翻译偶联来调节基因表达的机制。重叠的代码的稳定性检查有关的重叠的信息成本和基因组的突变率。在一个给定的人口重叠的程度将趋于成为单态。基因向部分重叠的进化取决于重叠的凸成本函数。当重叠基因的表达相互排斥并且由野生型基因组的罕见突变产生时，重叠不会进化。假设重叠增加功能相关基因之间的耦合，有利于重叠的条件进行了探讨，基因激活和衰变的动力学。偶联对于其中在其5'端重叠的基因（前导基因）快速衰减而在3'端重叠的基因（诱导基因）缓慢衰减的基因是最有效的。如果基因表达可以自我反馈（自催化），那么高激活率有利于重叠。
When the same sequence of nucleotides codes for regions of more than one functional polypeptide, this sequence contains overlapping genes. Overlap is most common in rapidly evolving genomes with high mutation rates such as viruses, bacteria, and mitochondria. Overlap is thought to be important as: (1) a means of compressing a maximum amount of information into short sequences of structural genes; and (2) as a mechanism for regulating gene expression through translational coupling of functionally related polypeptides. The stability of overlapping codes is examined in relation to the information cost of overlap and the mutation rate of the genome. The degree of overlap in a given population will tend to become monomorphic. Evolution toward partial overlap of genes is shown to depend on a convex cost function of overlap. Overlap does not evolve when expression of overlapping genes is mutually exclusive and produced by rare mutations to the wild-type genome. Assuming overlap increases coupling between functionally related genes, the conditions favoring overlap are explored in relation to the kinetics of gene activation and decay. Coupling is most effective for genes in which the gene overlapping at its 5' end (leading gene) decays rapidly, while the gene overlapping at the 3' end (induced gene) decays slowly. If gene expression can feedback on itself (autocatalysis), then high rates of activation favor overlap.