REGULATION OF TRANSCRIPTION OF THE HUMAN T-CELL ANTIGEN RECEPTOR DELTA CHAIN GENE - A T-LINEAGE SPECIFIC ENHANCER ELEMENT IS LOCATED IN THE J-DELTA-3-C-DELTA INTRON

We have defined transcriptional enhancing sequences inside the TCR-δ gene locus, using transient transfections with constructs containing DNA fragments cloned upstream to a reporter gene fused to a heterologous promoter. A 14-kb DNA region extending from the Jδ3 segment to 6kb3' to Cδ was analyzed. We show the presence of positive regulatory sequences inside the Jδ3-Cδ intron and have localized these sequences to two DNA fragments of ~300 and 258 bp. Analysis of cell specificity of the activation of such sequences demonstrates a T cell pattern for one of the two fragments. The nucleotide sequence of the T cell-specific element shows motifs sharing homology with previously described core enhancers.