On the cover
Podosomes in a primary human macrophage are highlighted by expression of Lifeact-RFP. The cell is treated with nocodazole, inducing cell body retraction and podosome detachment. Respective video frames are given a time color code, starting with blue and ending with red. El Azzouzi et al. show that islets of the matrix metalloproteinase MT1-MMP, embedded in the plasma membrane beneath the podosome core structure, persist beyond podosome dissolution and work as memory devices for efficient reformation of podosomes.Image © 2016 El Azzouzi et al.
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People & Ideas
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The authors find that matrix metalloproteinase MT1-MMP is enriched at the plasma membrane of macrophage podosomes, where it persists beyond podosome lifetime and, through binding to the subcortical actin cytoskeleton, forms subcellular signposts that facilitate podosome reformation.
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