Isolation of a T cell specific cDNA clone possibly involved in the T cell activation pathway

A T cell specific cDNA clone, YT15, has been isolated using the technique of subtractive hybridization. This gene is expressed predominantly in thymocytes and encodes a newly identified intracytoplasmic protein specific for T cells, since neither the nucleotide sequence of the cDNA clone nor the deduced amino acid sequence has significant homology to sequences in the GenBank or NBRF databases. The level of transcription of this gene in human leukemic cell line, Jurkat, can be reduced by stimulation of the T cell receptor CD3 (TcR-T3) complex. In addition, the levels of these messages are also greatly enhanced in some TcR/T3 receptor mutants. These findings suggest that this gene product may be involved in a T cell activation pathway within the cell.