Multiple cis-acting elements regulate the expression of the early T cell activation antigen CD69.
CD69 is the earliest activation antigen expressed on T lymphocytes upon stimulation through the TCR, or with stimuli that mimic TCR triggering. Here we describe that the phorbol ester PMA and a calcium ionophore had a synergistic effect on both CD69 antigen expression and promoter activity in Jurkat cells, that was sensitive to cyclosporin A (CsA). CD69 promoter analysis indicated that the sequence -78 to +16 contained the elements responsible for PMA and PMA plus calcium ionophore induction, as well as CsA inhibition. Mutagenesis of two previously described AP-1 motifs did not affect either the basal or the inducible promoter activities. Electrophoretic mobility shift assays allowed the identification of three novel inducible complexes composed by Egr-1/Egr-3, Egr-1, and ATF-3/Fos. Mutation of each sequence resulted in a partial reduction of the basal promoter activity, whereas the inducibility by PMA plus calcium ionophore remained almost unaffected. It was necessary to combine at least two mutations to obtain a significative or complete reduction of the response to the mitogenic stimulus. These results indicate that the inducible expression of CD69 gene by mitogenic signals is regulated by multiple cis-acting elements and by the interplay of transcription factors of the AP-1, EGR and ATF/CREB families.
Castellanos
María del Carmen
Mdel C
Servicio de Inmunología, Hospital de la Princesa, UAM, Madrid, Spain.
López-Giral
Sonia
S
López-Cabrera
Manuel
M
de Landázuri
Manuel O
MO
D051700:Activating Transcription Factor 3; D015703:Antigens, CD / Q000235:genetics*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000235:genetics*; D000001:Calcimycin / Q000494:pharmacology; D004268:DNA-Binding Proteins / Q000502:physiology; D051766:Early Growth Response Protein 1; D051776:Early Growth Response Protein 3; D005786:Gene Expression Regulation; D006801:Humans; D017874:Immediate-Early Proteins; D019169:Jurkat Cells; D037181:Lectins, C-Type; D011401:Promoter Regions, Genetic; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D018808:Transcription Factor AP-1 / Q000502:physiology; D014157:Transcription Factors / Q000502:physiology; D014158:Transcription, Genetic; D000099192:CD69 Antigens
D051700:Activating Transcription Factor 3; D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D000001:Calcimycin; D004268:DNA-Binding Proteins; D051766:Early Growth Response Protein 1; D051776:Early Growth Response Protein 3; D017874:Immediate-Early Proteins; D037181:Lectins, C-Type; D013755:Tetradecanoylphorbol Acetate; D018808:Transcription Factor AP-1; D014157:Transcription Factors; D000099192:CD69 Antigens; C497325:EGR1 protein, human