Beschreibung:
<jats:p>Phosphatidylinositol 5‐phosphate (PtdIns5P) is emerging as a potential lipid messenger involved in several cell types, from plants to mammals. Expression of IpgD, a PtdIns(4, 5)P<jats:sub>2</jats:sub> 4‐phosphatase induces Src kinase and Akt, but not ERK activation and enhances interleukin II promoter activity in T‐cells. Expression of a new PtdIns5P interacting domain blocks IpgD‐induced T‐cell activation and selective signaling molecules downstream of TCR triggering. Altogether, these data suggest that PtdIns5P may play a sensor function in setting the threshold of T‐cell activation and contributing to maintain T‐cell homeostasis.</jats:p>