Why all play makes Jack a smart boy Motor protein KIF1A essential for formation of new synapses and learning enhancement in enriched environment

May 17, 2012

It is known that experience of an enriched environment that provides many stimuli, including opportunities for communication and exercise, can improve memory and learning. Additionally, such an environment can have a beneficial effect on Alzheimer’s and other brain disorders.

© Nobutaka Hirokawa

Additionally, experience of an enriched environment brings about cellular changes in neurons, including synapse creation in the hippocampus, which is responsible for memory, and an increase in neurotrophins essential for neural function such as brain-derived neurotrophic factor (BDNF). However, the mechanism of these cellular and behavioral changes remained unknown.

Professor Nobutaka Hirokawa and his colleagues at the University of Tokyo’s Graduate School of Medicine have shown for the first time that the motor protein KIF1A, known to be involved in the transport of compounds essential for neural signaling, has a vital role in memory and learning enhancement due to an enriched environment.

The research group determined that the quantity of BDNF and KIF1A was elevated in the hippocampi of mice raised in an enriched environment. However, even when raised in an enriched environment, a genetically-engineered mouse with a reduced ability to express KIF1A showed no increase in hippocampal synapse formation, and no improved learning ability measured through behavioral tests such as finding a goal in a pool.

This result is an important step toward a fundamental understanding of the mechanism by which environmental stimuli effect transformations in the brain, and may suggest new approaches to treating brain disorders.

Department release/press release


Makoto Kondo, Yosuke Takei, and Nobutaka Hirokawa,
“Motor protein KIF1A is essential for hippocampal synaptogenesis and learning enhancement in an enriched environment”,
Neuron Vol.73 Issue 4, 743–757, doi:10.1016/j.neuron.2011.12.020
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