Super-resolution mapping of dendritic spines

2017 Fiscal Year Final Research Report

• Project/Area Number: 16K14568
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Nerve anatomy/Neuropathology
• Research Institution: Kyushu University (2017); Institute of Physical and Chemical Research (2016)
• Principal Investigator: Imai Takeshi 九州大学, 医学研究院, 教授 (70509851)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: 超解像顕微鏡 / コネクトミクス / シナプス / 樹状突起スパイン / 生後発達

Outline of Final Research Achievements

It is generally believed that the number of dendritic spines increases during childhood, and then declines during adolescence to form mature neuronal circuits. However, distribution of dendritic spines at a whole-neuron scale is not fully established. Here we performed comprehensive super-resolution mapping of dendritic spines in layer 5 cortical pyramidal neurons in mice. We found that spine density is highly biased at the middle compartment of long apical dendrites (spine density “hotspot”), demonstrating ~10-fold accumulations. In contrast, the spine density was less biased in layer 2/3 neurons and basal dendrites of layer 5 neurons. We also found that spine density at the hotspot increased during adolescence in an NMDAR-dependent manner, when other parts of the dendrites underwent moderate reduction. Thus, the spine density is “reorganized”, rather than simply decreased during adolescence to form mature cortical circuits.

Free Research Field

神経科学