A paradox in the hippocampus. Immature dentate granule cells are often described as the “plasticity reserve” of the hippocampus. They provide a pool of neurons that integrate into existing circuits, supporting learning, memory, and repair. In neurological disease, these cells have been suggested to buffer against injury or degeneration. In a recent publication, researchers showed that the hippocampus continues to generate new neurons throughout life, but that the molecular instructions for doing so vary dramatically across species. The surprising finding is this: the processes of neurogenesis are conserved, while the genes underlying these processes are often completely different. This is an important reminder that biology often converges at the level of function, even when the building blocks are not the same.
Tag Archives: Single cell sequencing
The mosaic brain – single neuron copy number variations in humans
Variability. It has been rumored for quite some time, but only now is solid evidence present to show this phenomenon: the high degree of genomic diversity of human neurons. In a recent paper in Science, the genomic diversity among frontal brain neurons is explored on a cell-by-cell basis. The results are breathtaking: up to 40% of frontal cortex neurons have altered genomic material affected by large deletions or duplications. This study provides the linchpin for a plethora of new investigations aiming to understand the impact of this phenomenon in health and disease. Continue reading