TY - JOUR
T1 - Cytochemical observation of regulated bacterial β-galactosidase gene expression in mammalian cells
AU - Liu, H. S.
AU - Feliciano, E. S.
AU - Stambrook, P. J.
PY - 1989
Y1 - 1989
N2 - Bacterial β-galactosidase, encoded by the lacZ gene, serves as a sensitive cytochemical marker in eukaryotic cells and tissues. In transient expression experiments, human and simian cells stain blue 48 hr after transfection with a plasmid containing a lacZ gene, whose expression is directed by a simian virus 40 promoter containing a synthetic lactose operator sequence. Transfection efficiency was about 0.6%. Incorporation of an operator sequence within the promoter permits regulation of β-galactosidase gene expression by the lacI gene product, the lac repressor. When cells were cotransfected with the lacZ plasmid and a second plasmid containing the lacI gene, β-galactosidase activity was extinguished. Its activity could be reestablished to original levels upon application of isopropyl β-D-thiogalactoside to transfected cells. A cell line that stably carries both the lacI and lacZ genes was efficiently induced to synthesize β-galactosidase after isopropyl β-D-thiogalactoside administration. In transient expression experiments and in stably transfected lines, repression and induction of β-galactosidase activity were predominantly at the transcriptional level.
AB - Bacterial β-galactosidase, encoded by the lacZ gene, serves as a sensitive cytochemical marker in eukaryotic cells and tissues. In transient expression experiments, human and simian cells stain blue 48 hr after transfection with a plasmid containing a lacZ gene, whose expression is directed by a simian virus 40 promoter containing a synthetic lactose operator sequence. Transfection efficiency was about 0.6%. Incorporation of an operator sequence within the promoter permits regulation of β-galactosidase gene expression by the lacI gene product, the lac repressor. When cells were cotransfected with the lacZ plasmid and a second plasmid containing the lacI gene, β-galactosidase activity was extinguished. Its activity could be reestablished to original levels upon application of isopropyl β-D-thiogalactoside to transfected cells. A cell line that stably carries both the lacI and lacZ genes was efficiently induced to synthesize β-galactosidase after isopropyl β-D-thiogalactoside administration. In transient expression experiments and in stably transfected lines, repression and induction of β-galactosidase activity were predominantly at the transcriptional level.
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U2 - 10.1073/pnas.86.24.9951
DO - 10.1073/pnas.86.24.9951
M3 - Article
C2 - 2481319
AN - SCOPUS:0024850432
SN - 0027-8424
VL - 86
SP - 9951
EP - 9955
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 24
ER -