An evolutionary perspective on protein moonlighting.
An evolutionary perspective on protein moonlighting.
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从进化角度看蛋白质兼职。
DOI：
10.1042/bst20140245
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发表时间：
2014-12
影响因子：
3.9
通讯作者：
Copley SD
中科院分区：
文献类型：
--
作者：
Copley SD
兼职蛋白除了它们的典型作用之外还提供一种或多种额外的功能。当蛋白质和新伴侣之间的偶然相互作用改善了生物体的适应性时，兼职功能就会出现。选择性地施加压力，要求改进新功能，可能会导致两种结果。编码新的双功能蛋白质的基因可以复制和分化，从而编码两种蛋白质，每种蛋白质仅具有一种功能。或者，遗传变化，最大限度地减少两种功能之间的适应性冲突和/或改善控制的时间和地点，在每个功能的服务，可以导致兼职蛋白质。重要的是，增强兼职功能的遗传变化可以发生在编码兼职蛋白本身的基因中，也可以发生在影响其新伴侣结构的基因中，或者发生在编码控制任一伴侣表达的转录因子的基因中。每种兼职蛋白质的进化历史都很复杂，取决于基因复制和点突变等遗传变化的随机发生，以及这些变化对适应度的影响。群体效应，特别是由于随机遗传漂变而导致的有前途个体的损失，也在兼职蛋白的出现中发挥了作用。最终的结果不一定是服务于两个功能的问题的“最优”解决方案，但可能是“足够好”的，适应性受到其他功能的限制。
Moonlighting proteins serve one or more additional functions in addition to their canonical roles. Moonlighting functions arise when an adventitious interaction between a protein and a new partner improves fitness of the organism. Selective pressure for improvement in the new function can result in two alternative outcomes. The gene encoding the newly bi-functional protein may duplicate and diverge so as to encode two proteins, each of which serves only one function. Alternatively, genetic changes that minimize adaptive conflict between the two functions and/or improve control over the time and place at which each function is served can lead to a moonlighting protein. Importantly, genetic changes that enhance a moonlighting function can occur in the gene encoding the moonlighting protein itself, in a gene that affects the structure of its new partner, or in a gene encoding a transcription factor that controls expression of either partner. The evolutionary history of each moonlighting protein is complex, depending upon the stochastic occurrence of genetic changes such as gene duplication and point mutations, and the effects of those changes on fitness. Population effects, particularly loss of promising individuals due to random genetic drift, also play a role in the emergence of a moonlighting protein. The ultimate outcome is not necessarily the “optimal” solution to the problem of serving two functions, but may be “good enough” that fitness becomes limited by some other function.