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Updated: May 23, 2026

In situ Subcellular Fractionation of Adherent and Non-adherent Mammalian Cells
Published on: July 23, 2010
Segregation of molecules at cell division reveals native protein localization
Dirk Landgraf1, Burak Okumus, Peter Chien
1Department of Systems Biology, Harvard Medical School, Boston, Massachusetts, USA.
Abstract:
We introduce a nonintrusive method exploiting single-cell variability after cell division to validate protein localization. We found that Clp proteases, widely reported to form biologically relevant foci, were uniformly distributed in Escherichia coli cells, and that many commonly used fluorescent proteins caused severe mislocalization when fused to homo-oligomers. Retagging five other reportedly foci-forming proteins with the most monomeric fluorescent protein tested suggests that the foci were caused by the fluorescent tags.
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