Photoactivation turns green fluorescent protein red
Abstract
In the few years since its gene was first cloned, the Aequorea victoria green fluorescent protein (GFP) has become a powerful tool in cell biology, functioning as a marker for gene expression, protein localization and protein dynamics in living cells [1], [2], [3]. GFP variants with improved fluorescence intensity and altered spectral characteristics have been identified, but additional GFP variants are still desirable for multiple labeling experiments, protein interaction studies and improved visibility in some organisms [4]. In particular, long-wavelength (red) fluorescence has remained elusive. Here we describe a red-emitting, green-absorbing fluorescent state of GFP that is generated by photoactivation with blue light. GFP can be switched to its red-emitting state easily with a laser or fluorescence microscope lamp under conditions of low oxygen concentration. This previously unnoticed ability enables regional, non-invasive marking of proteins in vivo. In particular, we report here the use of GFP photoactivation to make the first direct measurements of protein diffusion in the cytoplasm of living bacteria.
Additional Information
© 1997 Elsevier Science Ltd. Received 2 July 1997, Revised 25 July 1997, Accepted 8 August 1997, Available online 10 April 2004. We are grateful to Hannah R. Morris and Patrick J. Treado for generous assistance with spectral imaging; to Lotti Frisen for help photoactivating yeast; to Andrew Beavis and Jerome Zawadski for assistance with lasers; to R. Tsien and B. Cormack for providing GFP mutants; and to Philippe Cluzel, Lotti Frisen, Andrew Murray, Kevan Shokat, Thomas Surrey, and Feng Yang for helpful discussions and encouragement. This work has been partially supported by grants from the N.I.H., the N.S.F., and the H.F.S.P. (to S.L.).Additional details
- Eprint ID
- 102881
- Resolver ID
- CaltechAUTHORS:20200428-133426011
- NIH
- NSF
- Human Frontier Science Program
- Created
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2020-04-28Created from EPrint's datestamp field
- Updated
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2021-11-16Created from EPrint's last_modified field