Related Experiment Video
Updated: Feb 13, 2026

Imaging Dendritic Spines in Caenorhabditis elegans
Published on: September 27, 2021
Isoform-dependent Regulation of Drebrin Dynamics in Dendritic Spines
Kenji Hanamura1, Yousuke Kamata1, Hiroyuki Yamazaki1
1Department of Neurobiology and Behavior, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan.
Abstract:
Dendritic spines have stable filamentous actin (F-actin) and dynamic F-actin. The formation of stable F-actin plays a pivotal role in spine formation. Drebrin binds to and stabilizes F-actin in dendritic spines. Interestingly, the conversion of the drebrin E isoform to drebrin A occurs in parallel with synapse formation, suggesting that this conversion promotes synapse formation via F-actin accumulation. In this study, we measured the dynamics of GFP-tagged drebrin E (GFP-DE) and drebrin A (GFP-DA) in cultured hippocampal neurons by fluorescence recovery after photobleaching analysis. We found that GFP-DA has a larger stable fraction than GFP-DE. The stable drebrin fraction reflects its accumulation in dendritic spines, therefore the isoform conversion may increase the amount of stable F-actin in dendritic spines. The stable fraction was dependent on the drebrin A-specific sequence "Ins2", located in the middle of the drebrin protein. In addition, F-actin depolymerization with latrunculin A significantly reduced the stable GFP-DA fraction. These findings indicate that preferential binding of drebrin A to F-actin than drebrin E causes higher stable fraction of drebrin A in dendritic spines, although the F-actin-binding ability of purified drebrin E and drebrin A are comparable. Therefore, we suggest that a drebrin isoform conversion from drebrin E to drebrin A in dendritic spines results in the accumulation of drebrin-bound stable F-actin, which plays a pivotal role in synapse formation.
Related Concept Videos
Contact-dependent Signaling
Gap Junctions
In animal cells, gap junctions are formed...
Regulated Protein Degradation
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Positive Regulator Molecules
Epigenetic Regulation
GTPases and their Regulation
Large G-proteins,...
Frequency-dependent Selection

