Department of Biology, Utrecht University, Utrecht, The Netherlands.
PLoS Comput Biol. 2024 Feb 9;20(2):e1011860. doi: 10.1371/journal.pcbi.1011860. eCollection 2024 Feb.
The complex eukaryotic cell resulted from a merger between simpler prokaryotic cells, yet the role of the mitochondrial endosymbiosis with respect to other eukaryotic innovations has remained under dispute. To investigate how the regulatory challenges associated with the endosymbiotic state impacted genome and network evolution during eukaryogenesis, we study a constructive computational model where two simple cells are forced into an obligate endosymbiosis. Across multiple in silico evolutionary replicates, we observe the emergence of different mechanisms for the coordination of host and symbiont cell cycles, stabilizing the endosymbiotic relationship. In most cases, coordination is implicit, without signaling between host and symbiont. Signaling only evolves when there is leakage of regulatory products between host and symbiont. In the fittest evolutionary replicate, the host has taken full control of the symbiont cell cycle through signaling, mimicking the regulatory dominance of the nucleus over the mitochondrion that evolved during eukaryogenesis.
真核生物细胞是由较为简单的原核细胞合并而成的，然而线粒体的内共生对于其他真核生物创新的作用仍然存在争议。为了研究与内共生状态相关的调控挑战如何影响真核生物发生过程中的基因组和网络进化，我们研究了一个建设性的计算模型，其中两个简单的细胞被迫进行专性内共生。在多次计算机模拟进化复制中，我们观察到了协调宿主和共生细胞周期的不同机制的出现，从而稳定了内共生关系。在大多数情况下，协调是隐式的，宿主和共生体之间没有信号传递。只有当宿主和共生体之间存在调控产物泄漏时，信号才会进化。在适应性最强的进化复制中，宿主通过信号完全控制了共生体的细胞周期，模拟了真核生物发生过程中核对线粒体的调控优势。
