Glutamate-specific gene linked to human brain evolution enhances synaptic plasticity and cognitive processes
- Author: mycolabadmin
- 1/19/2024
- View Source
Summary
Scientists discovered that a human gene called GLUD2, which evolved as our brains expanded, makes synapses stronger and more plastic through a lactate-dependent process. When they added this gene to mice, the animals showed improved memory, better learning ability, and stronger brain connections. This research suggests that GLUD2 played a key role in the evolution of human intelligence by enhancing the brain’s ability to form new neural connections and adapt to new information.
Background
The human brain is distinguished by elevated expression of proteins involved in synaptic transmission and energy metabolism, particularly glutamatergic signaling. The GLUD2 gene emerged in hominoid ancestors and evolved under positive selection concomitantly with brain expansion, encoding a unique glutamate dehydrogenase isoform with enhanced catalytic properties.
Objective
To investigate whether transgenic expression of the human GLUD2 gene enhances structural, physiological, and behavioral aspects of cognitive function by studying transgenic mice carrying the GLUD2 gene.
Results
GLUD2 was expressed in hippocampal pyramidal neurons and astrocytes. Transgenic mice exhibited markedly enhanced long-term potentiation via a lactate-dependent mechanism, increased dendritic spine density throughout lifespan, enhanced synaptogenesis, increased pain sensitivity, and improved performance on complex cognitive tasks including behavioral flexibility and contextual fear extinction.
Conclusion
GLUD2 enhances synaptic plasticity and cognitive processes through lactate-mediated astrocyte-neuron interaction and NMDA receptor signaling, suggesting the gene likely contributed to human brain evolution by promoting structural and functional neural connectivity underlying cognitive abilities.
- Published in:iScience,
- Study Type:Experimental Study,
- Source: PMID: 38333701