Functional analysis of the murine T-cell receptor beta enhancer and characteristics of its DNA-binding proteins.
The minimal T-cell receptor (TCR) beta-chain (TCR beta) enhancer has been identified by transfection into lymphoid cells. The minimal enhancer was active in T cells and in some B-lineage cells. When a larger fragment containing the minimal enhancer was used, its activity was apparent only in T cells. Studies with phytohemagglutinin and 4 beta-phorbol-12,13-dibutyrate revealed that the enhancer activity was increased by these agents. By a combination of DNase I footprinting, gel mobility shift assay, and methylation interference analysis, seven different motifs were identified within the minimal enhancer. Furthermore, competition experiments showed that some of these elements bound identical or similar factors that are known to bind to the TCR V beta promoter decamer or to the immunoglobulin enhancer kappa E2 or muEBP-E motif. These shared motifs may be important in the differential gene activity among the different lymphoid subsets.
Takeda
J
J
Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri 63110.
Cheng
A
A
Mauxion
F
F
Nelson
C A
CA
Newberry
R D
RD
Sha
W C
WC
Sen
R
R
Loh
D Y
DY
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D003001:Cloning, Molecular; D004252:DNA Mutational Analysis; D004268:DNA-Binding Proteins / Q000502:physiology*; D004742:Enhancer Elements, Genetic; D005786:Gene Expression Regulation; D008214:Lymphocytes / Q000502:physiology*; D051379:Mice; D008969:Molecular Sequence Data; D015240:Phorbol 12,13-Dibutyrate / Q000494:pharmacology; D010835:Phytohemagglutinins / Q000494:pharmacology; D011401:Promoter Regions, Genetic; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D016693:Receptors, Antigen, T-Cell, alpha-beta; D015183:Restriction Mapping; D013329:Structure-Activity Relationship
D004268:DNA-Binding Proteins; D010835:Phytohemagglutinins; D011948:Receptors, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta; D015240:Phorbol 12,13-Dibutyrate