Phosphorylation of the ARE-binding protein DAZAP1 by ERK2 induces its dissociation from DAZ

Simon Morton, Huei Ting Yang, Ntsane Moleleki, David G. Campbell, Philip Cohen, Simon Rousseau

    Research output: Contribution to journalArticlepeer-review

    26 Citations (Scopus)

    Abstract

    A protein in RAW 264.7 macrophages, which became phosphorylated in response to LPS (lipopolysaccharide), was identified as the RNA-binding protein called DAZAP1 [DAZ (deleted in azoospermia)-associated protein 1]. The phosphorylation of this protein was prevented by specific inhibition of MKK1 [MAPK (mitogen-activated protein kinase) kinase 1], indicating that it was phosphorylated via the classical MAPK cascade. Further experiments showed that DAZAP1 was phosphorylated stoichiometrically in vitro by ERK2 (extracellular-signal-regulated protein kinase 2) at two Thr-Pro sequences (Thr269 and Thr315), and that both sites became phosphorylated in HEK-293 (human embryonic kidney 293) cells in response to PMA or EGF (epidermal growth factor), or RAW 264.7 macrophages in response to LPS. Phosphorylation induced by each stimulus was prevented by two structurally distinct inhibitors of MKK1 (PD184352 and U0126), demonstrating that DAZAP1 is a physiological substrate for ERK1/ERK2. The mutation of Thr269 and Thr315 to aspartate or the phosphorylation of these residues caused DAZAP1 to dissociate from its binding partner DAZ. DAZ interacts with PABP [poly(A)-binding protein] and thereby stimulates the translation of mRNAs containing short poly(A) tails [Collier, Gorgoni, Loveridge, Cooke and Gray (2005) EMBO J. 24, 2656-2666]. In the present study we have shown that DAZ cannot bind simultaneously to DAZAP1 and PABP, and suggest that the phosphorylation-induced dissociation of DAZ and DAZAP1 may allow the former to stimulate translation by interacting with PABP.

    Original languageEnglish
    Pages (from-to)265-273
    Number of pages9
    JournalBiochemical Journal
    Volume399
    Issue number2
    DOIs
    Publication statusPublished - 15 Oct 2006

    Keywords

    • AU-rich element (ARE)
    • Deleted in azoospermia (DAZ)
    • Deleted-in-azoospermia- associated protein 1 (DAZAP1)
    • Extracellular-signal-regulated protein kinase (ERK)
    • mRNA stability
    • mRNA translation

    Fingerprint

    Dive into the research topics of 'Phosphorylation of the ARE-binding protein DAZAP1 by ERK2 induces its dissociation from DAZ'. Together they form a unique fingerprint.

    Cite this