Open AccessThe p38/MK2-Driven Exchange between Tristetraprolin and HuR Regulates AU–Rich Element–Dependent Translation
Author(s) -
Christopher Tiedje,
Natalia Ronkina,
Mohammad H. Jalilian Tehrani,
Sonam Dhamija,
Kathrin Laaß,
Helmut Holtmann,
Alexey Kotlyarov,
Matthias Gaestel
Publication year - 2012
Publication title -
plos genetics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.587
H-Index - 233
eISSN - 1553-7404
pISSN - 1553-7390
DOI - 10.1371/journal.pgen.1002977
Subject(s) - tristetraprolin , phosphorylation , au rich element , translation (biology) , p38 mitogen activated protein kinases , messenger rna , microbiology and biotechnology , eukaryotic translation , biology , mapk/erk pathway , rna binding protein , biochemistry , gene
TNF expression of macrophages is under stringent translational control that depends on the p38 MAPK/MK2 pathway and the AU–rich element (ARE) in the TNF mRNA. Here, we elucidate the molecular mechanism of phosphorylation-regulated translation of TNF. We demonstrate that translation of the TNF-precursor at the ER requires expression of the ARE–binding and -stabilizing factor human antigen R (HuR) together with either activity of the p38 MAPK/MK2 pathway or the absence of the ARE-binding and -destabilizing factor tristetraprolin (TTP). We show that phosphorylation of TTP by MK2 decreases its affinity to the ARE, inhibits its ability to replace HuR, and permits HuR-mediated initiation of translation of TNF mRNA. Since translation of TTP's own mRNA is also regulated by this mechanism, an intrinsic feedback control of the inflammatory response is ensured. The phosphorylation-regulated TTP/HuR exchange at target mRNAs provides a reversible switch between unstable/non-translatable and stable/efficiently translated mRNAs.