Molecular mechanisms of the effect of herpesvirus saimiri protein StpC on the signaling pathway leading to NF-kappaB activation.

Herpesvirus saimiri (Saimiriine herpesvirus-2) causes lethal T lymphoproliferative diseases in the susceptible species and transforms T lymphocytes to continuous growth in vitro. H. saimiri-induced transformation of T cells is becoming an important experimental tool of biomedical research.

Protein tyrosine phosphorylation in T cell signaling.

This review discusses in considerable detail the tyrosine phosphorylation events that couple the T cell antigen receptor to downstream signaling pathways. First, the protein kinases that catalyze these tyrosine phosphorylation are introduced, then the phosphatases that mediate removal of phosphate from tyrosine residues. Next, we discuss the molecular clock work by which these enzymes initiated T cell activation.

Inhibition of T cell antigen receptor signaling by VHR-related MKPX (VHX), a new dual specificity phosphatase related to VH1 related (VHR).

A cDNA encoding a novel, human, dual-specific protein phosphatase was identified in the Incyte data base. The open reading frame predicted a protein of 184 amino acids related to the Vaccinia virus VH1 and human VH1-related (VHR) phosphatases. Expression VHR-related MKPX (VHX) was highest in thymus, but also detectable in monocytes and lymphocytes.