K. Hardy et G. Chaudhri, ACTIVATION AND SIGNAL-TRANSDUCTION VIA MITOGEN-ACTIVATED PROTEIN (MAP) KINASES IN T-LYMPHOCYTES, Immunology and cell biology, 75(6), 1997, pp. 528-545
The various mitogen-activated protein (MAP) kinases have central roles
in the signalling pathways of T lymphocytes. Their activation is uniq
uely dependent on dual phosphorylation of a serine/threonine and a tyr
osine residue and is regulated by several levels of kinases in paralle
l cascades. In addition, both the MAP kinases and their upstream, acti
vating kinases are regulated by several phosphatases. Although each of
the MAP kinases have many cytoplasmic substrates, their ability to tr
anslocate to the nucleus means that they can transmit signals from the
cytoplasm directly to transcription factors, which are sometimes nucl
ear bound. The MAP kinase cascades are activated in T lymphocytes by a
variety of different external stimuli. They play an important role in
transducing both the signal from T cell receptor and costimulatory mo
lecules, on the T cell surface, and are able to regulate several of th
e transcription factors controlling the expression of critical genes,
including that for IL-2. This review examines how the activation of se
veral MAP kinases is regulated, their role in signal transduction init
iated by a variety of stimuli, and how this may lead to different cell
ular responses.