Cellular and Molecular Life Sciences

, Volume 69, Issue 7, pp 1025–1033 | Cite as

GFP tagging sheds light on protein translocation: implications for key methods in cell biology

  • Marcel DeponteEmail author
Visions and reflections


Green fluorescent protein (GFP) is a powerful tool for studying gene expression, protein localization, protein–protein interactions, calcium concentrations, and redox potentials owing to its intrinsic fluorescence. However, GFP not only contains a chromophore but is also tightly folded in a temperature-dependent manner. The latter property of GFP has recently been exploited (1) to characterize the translocase of the outer mitochondrial membrane and (2) to discriminate between protein transport across and into biomembranes in vivo. I therefore suggest that GFP could be a valuable tool for the general analysis of protein transport machineries and pathways in a variety of organisms. Moreover, results from such studies could be important for the interpretation and optimization of classical experiments using GFP tagging.


Green fluorescent protein Protein translocase Protein transport machineries Protein localization GFP tagging 



I thank the Deutsche Forschungsgemeinschaft (DFG) for financial support of my work on mitochondrial protein transport (Grant DE 1431/2). I would also like to thank Max Harner for his extraordinary work on the TOM complex.


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© Springer Basel AG 2012

Authors and Affiliations

  1. 1.Department of ParasitologyRuprecht-Karls UniversityHeidelbergGermany

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