Functional analysis of c-Myb protein in T-lymphocytic cell lines shows that it trans-activates the c-myc promoter.
The function of c-Myb protein was revealed by transfecting an expression vector containing the entire c-Myb protein-coding sequence into the murine CTLL-2 T-cell line. Expressions of high levels of c-Myb protein did not alter the expression of several T-cell markers, c-fos mRNA expression, responses to interleukin-2, and growth characteristics of these cells. Interestingly, expression of the c-myc gene was drastically increased in this clone. Further, the c-myb expression plasmid, but not a frameshift mutant of c-myb, enhanced the expression of a hybrid construct of c-myc promoter linked to a reporter gene by 8- to 14-fold. These results demonstrate a role of c-Myb protein in c-myc gene expression.
Evans
J L
JL
Lineberger Cancer Research Center, Department of Microbiology-Immunology, University of North Carolina, Chapel Hill 27599-7295.
Moore
T L
TL
Kuehl
W M
WM
Bender
T
T
Ting
J P
JP
D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics; D005786:Gene Expression Regulation; D051379:Mice; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D011401:Promoter Regions, Genetic; D011505:Protein-Tyrosine Kinases / Q000235:genetics*; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D020598:Proto-Oncogene Proteins c-myb; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics*; D011519:Proto-Oncogenes; D015183:Restriction Mapping; D013601:T-Lymphocytes; D014162:Transfection
D015345:Oligonucleotide Probes; D011518:Proto-Oncogene Proteins; D020598:Proto-Oncogene Proteins c-myb; D016271:Proto-Oncogene Proteins c-myc; D015500:Chloramphenicol O-Acetyltransferase; D011505:Protein-Tyrosine Kinases