Institute for Biological and Medical Imaging, Helmholtz Zentrum Munich, German Research Center for Environmental Health, Neuherberg, Germany; International Centre for Neurotherapeutics, Dublin City University, Dublin, Ireland; Department of Experimental Neurobiology, National Institute of Mental Health, Klecany, Czech Republic; Department of Psychiatry and Medical Psychology, 3rd Faculty of Medicine of Charles University, Prague, Czech Republic.
Department of Medical Genetics, Third Faculty of Medicine, Charles University, Ruská, Czech Republic.
Vitam Horm. 2020;114:1-21. doi: 10.1016/bs.vh.2020.04.009. Epub 2020 Jul 3.
Synaptic transmission is a fundamental neurobiological process by which neurons interact with each other and non-neuronal cells. It involves release of active substances from the presynaptic neuron onto receptive elements of postsynaptic cells, inducing waves of spreading electrochemical response. While much has been learned about the cellular and molecular mechanisms driving and governing transmitter release and sensing, the evolutionary origin of synaptic connections remains obscure. Herein, we review emerging evidence and concepts suggesting that key components of chemical synapse arose independently from neurons, in different functional and biological contexts, before the rise of multicellular living forms. We argue that throughout evolution, distinct synaptic constituents have been co-opted from ancestral forms for a new role in early metazoan, leading to the rise of chemical synapses and neurotransmission. Such a mosaic model of the origin of chemical synapses agrees with and supports the pluralistic hypothesis of evolutionary change.
突触传递是神经元之间以及神经元与非神经元细胞相互作用的基本神经生物学过程。它涉及到前神经元从突触前神经元释放活性物质到突触后细胞的接受元件上，诱导电化学反应的传播波。虽然已经了解了驱动和控制递质释放和感知的细胞和分子机制，但突触连接的进化起源仍然不清楚。在此，我们回顾了新出现的证据和概念，这些证据和概念表明，在多细胞生物形式出现之前，化学突触的关键成分已经在不同的功能和生物环境中独立于神经元产生。我们认为，在整个进化过程中，不同的突触成分已经从祖先形式中被重新利用，在早期后生动物中发挥新的作用，从而导致了化学突触和神经传递的出现。这种化学突触起源的镶嵌模型与进化变化的多元假说一致，并支持该假说。
