Computer simulation on the cooperation of functional molecules during the early stages of evolution.
Computer simulation on the cooperation of functional molecules during the early stages of evolution.
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计算机模拟进化早期阶段功能分子的合作。
DOI：
10.1371/journal.pone.0035454
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发表时间：
2012
期刊：
影响因子：
3.7
通讯作者：
Hu J
中科院分区：
文献类型：
--
作者：
Ma W;Hu J
生命很可能始于一些RNA（或类RNA）分子，通过碱基配对进行自我复制，并表现出有利于自我复制的酶样功能。不同的功能分子可能通过在不同方面促进自身自我复制而出现。然后，实现复杂性/效率的直接途径可能是通过这些分子的共存/合作。然而，这条路线的可能性仍然相当不清楚，特别是因为这些分子将争夺有限的公共资源。通过使用蒙特卡罗模型（在核苷酸和膜成分水平上具有“微分辨率”）的计算机模拟，我们表明这些分子的共存/合作可以自然发生，无论是裸露形式还是原始细胞形式。计算机模拟的结果也导致了对场景中的环境和历史的相当多的推论。首先，裸露阶段（具有催化模板复制和代谢的功能分子）可能发生在进化早期，但需要系统的高浓度和有限的分散（例如，在某些矿物表面上）；原始细胞的出现使得“栖息地转变”为大量水。其次，原始细胞阶段始于“伪原始细胞”亚阶段，具有催化模板复制和代谢的功能分子，但仍缺少参与膜成分合成的功能，其出现将导致随后的“真原始细胞”亚阶段。第三，最初的不稳定膜由生命前可用的脂肪酸组成，应该很早就被更稳定的膜（例如，像现代细胞一样由磷脂组成）所取代。此外，膜接管可能发生在原始细胞两个亚阶段的转变时。本研究中描述的场景应该对应于早期进化的一个时期，在单个“基因”出现之后，但在具有连锁基因的“染色体”出现之前。
It is very likely that life began with some RNA (or RNA-like) molecules, self-replicating by base-pairing and exhibiting enzyme-like functions that favored the self-replication. Different functional molecules may have emerged by favoring their own self-replication at different aspects. Then, a direct route towards complexity/efficiency may have been through the coexistence/cooperation of these molecules. However, the likelihood of this route remains quite unclear, especially because the molecules would be competing for limited common resources. By computer simulation using a Monte-Carlo model (with “micro-resolution” at the level of nucleotides and membrane components), we show that the coexistence/cooperation of these molecules can occur naturally, both in a naked form and in a protocell form. The results of the computer simulation also lead to quite a few deductions concerning the environment and history in the scenario. First, a naked stage (with functional molecules catalyzing template-replication and metabolism) may have occurred early in evolution but required high concentration and limited dispersal of the system (e.g., on some mineral surface); the emergence of protocells enabled a “habitat-shift” into bulk water. Second, the protocell stage started with a substage of “pseudo-protocells”, with functional molecules catalyzing template-replication and metabolism, but still missing the function involved in the synthesis of membrane components, the emergence of which would lead to a subsequent “true-protocell” substage. Third, the initial unstable membrane, composed of prebiotically available fatty acids, should have been superseded quite early by a more stable membrane (e.g., composed of phospholipids, like modern cells). Additionally, the membrane-takeover probably occurred at the transition of the two substages of the protocells. The scenario described in the present study should correspond to an episode in early evolution, after the emergence of single “genes”, but before the appearance of a “chromosome” with linked genes.
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DOI：
10.1023/b:orig.0000043130.49790.a7
发表时间：
2004-12-01
影响因子：
2
作者：
Ertem, G
通讯作者：
Ertem, G
影响因子：
3.5
作者：
Biondi, Elisa;Branciamore, Sergio;Gallori, Enzo
通讯作者：
Gallori, Enzo
影响因子：
2
作者：
Fontanari, JF;Santos, M;Szathmáry, E
通讯作者：
Szathmáry, E
影响因子：
3.9
作者：
Branciamore, Sergio;Gallori, Enzo;Czaran, Tamas
通讯作者：
Czaran, Tamas
影响因子：
64.8
作者：
ACEVEDO, OL;ORGEL, LE
通讯作者：
ORGEL, LE