IL2 Inducible T-Cell Kinase (ITK)

A single 6.2-kb mRNA and 72-kD protein were detected in T lymphocytes and NK-like cell lines, but were not detected in other cell lineages. Sequence comparisons suggested that the protein is probably the human homolog of a murine interleukin-2-inducible T-cell kinase (ITK). However, unlike ITK, the message and protein levels for the new entity did not vary markedly on stimulation of human IL-2 responsive T cells with IL-2. They referred to the gene and its protein product as EMT. They concluded that EMT is a member of a new family of intracellular kinases that includes BPK. The expression of EMT message and protein in thymocytes and mature T cells, combined with its homology to BPK and its chromosomal localization, suggested that EMT may play a role in thymic ontogeny and growth regulation of mature T cells.