Dimensions Dictate Decay Rates

Science's STKE  14 Nov 2000:
Vol. 2000, Issue 58, pp. tw7
DOI: 10.1126/stke.2000.58.tw7

Dendritic spines are highly mobile structures that are the location of most synaptic input in the central nervous system in mammals. Majewska, Tashiro, and Yuste found a strong correlation between the length of the spine neck and diffusion rates out of the spine, measured as recovery after photobleaching of enhanced green fluorescent protein. They also observed that calcium transients had slower decay kinetics when the spine necks were elongated than when they were short and that the kinetics altered within a single spine as the neck length changed. Although the cause-and-effect relation is not discernible at this time, their data suggest that spine motility may contribute to the compartmentalization of calcium and, thus, may influence synaptic plasticity and responsiveness.

Majewska, A., Tashiro, A., and Yuste, R. (2000) Regulation of spine calcium dynamics by rapid spine motility. J. Neurosci. 20: 8262-8268. [Abstract] [Full Text]