Abstract
We directly observed real-time production of single protein molecules in individual Escherichia coli cells. A fusion protein of a fast-maturing yellow fluorescent protein (YFP) and a membrane-targeting peptide was expressed under a repressed condition. The membrane-localized YFP can be detected with single-molecule sensitivity. We found that the protein molecules are produced in bursts, with each burst originating from a stochastically transcribed single messenger RNA molecule, and that protein copy numbers in the bursts follow a geometric distribution. The quantitative study of low-level gene expression demonstrates the potential of single-molecule experiments in elucidating the workings of fundamental biological processes in living cells.
Publication types
-
Research Support, N.I.H., Extramural
-
Research Support, U.S. Gov't, Non-P.H.S.
MeSH terms
-
Bacterial Proteins / analysis
-
Bacterial Proteins / biosynthesis
-
Bacterial Proteins / genetics
-
Blotting, Western
-
Escherichia coli K12 / genetics*
-
Escherichia coli K12 / metabolism
-
Escherichia coli Proteins / analysis
-
Escherichia coli Proteins / biosynthesis*
-
Escherichia coli Proteins / genetics
-
Fluorescence
-
Gene Expression Profiling / methods*
-
Gene Expression*
-
Luminescent Proteins / analysis
-
Luminescent Proteins / biosynthesis
-
Luminescent Proteins / genetics
-
Membrane Proteins / analysis
-
Membrane Proteins / biosynthesis
-
Membrane Proteins / genetics
-
Microscopy, Fluorescence
-
Molecular Probe Techniques
-
Poisson Distribution
-
Promoter Regions, Genetic
-
RNA, Bacterial / genetics
-
RNA, Bacterial / metabolism
-
RNA, Messenger / genetics
-
RNA, Messenger / metabolism
-
Recombinant Fusion Proteins / analysis
-
Recombinant Fusion Proteins / biosynthesis
-
Reverse Transcriptase Polymerase Chain Reaction
-
Stochastic Processes
Substances
-
Bacterial Proteins
-
Escherichia coli Proteins
-
Luminescent Proteins
-
Membrane Proteins
-
RNA, Bacterial
-
RNA, Messenger
-
Recombinant Fusion Proteins
-
Tsr protein, Bacteria
-
yellow fluorescent protein, Bacteria