Editors' ChoiceBiochemistry

Real-Life Transcription Factor Dynamics

Science's STKE  29 May 2007:
Vol. 2007, Issue 388, pp. tw190
DOI: 10.1126/stke.3882007tw190

Transcription factors bind to specific sites on chromosomal DNA to regulate gene expression. It is generally thought that transcription factors find their target DNA through a combination of diffusion through the cytoplasm and diffusion along DNA segments. Elf et al. use single-molecule techniques to study the specific and nonspecific binding of a model transcription factor, the lac repressor, in living Escherichia coli. Lac repressor searching for an operator spends 90% of its time diffusing along DNA. If the repressor does not find an operator within 5 milliseconds, it falls off the DNA and diffuses through the cytoplasm to bind to another DNA segment. Such single-molecule approaches will move us toward a quantitative understanding of biochemical processes as they occur in living cells.

J. Elf, G.-W. Li, X. S. Xie, Probing transcription factor dynamics at the single-molecule level in a living cell. Science 316, 1191-1194 (2007). [Abstract] [Full Text]

Related Content