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The birth of the synapse.
1Institute for Biological and Medical Imaging, Helmholtz Zentrum Munich, German Research Center for Environmental Health, Ingolstaedter Landstrasse 1, 85764, Neuherberg, Germany. saak.ovsepian@gmail.com.
Brain Structure & Function
|June 15, 2017
Summary
Chemical synapses, crucial for complex life, evolved from pre-existing cell structures before neurons emerged. This exaptive origin highlights evolutionary innovation without major genetic changes.
Area of Science:
- Evolutionary Biology
- Cell Biology
- Neuroscience
Background:
- The evolution of chemical synapses was traditionally linked to the emergence of neurons.
- Recent research suggests synaptic evolution predates neurons, originating in early metazoa and unicellular organisms.
Purpose of the Study:
- To explore the exaptive origin of chemical synapses.
- To discuss how existing cellular structures and signaling pathways were repurposed for synaptic function.
Main Methods:
- Review of emerging evidence on early cellular communication.
- Analysis of the exaptive potential of pre-existing junctional morphologies and paracrine signaling components.
Main Results:
- Chemical synapses likely arose from the modification and combination of pre-existing cellular structures and paracrine signaling mechanisms.
- This evolutionary pathway allowed for the development of complex regulatory and control systems in organisms.
Conclusions:
- The exaptive origin of chemical synapses provided significant evolutionary advantages without requiring large-scale genomic reorganization.
- This process profoundly impacted the evolution and diversity of life on Earth.
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