The MAPK phosphatase MKP1 (DUSP1) is overexpressed in many human cancers, including chemoresistant and radioresistant breast cancer cells, but its functional contributions in these settings are unclear. Here, we report that after cell irradiation, MKP1 translocates into mitochondria, where it prevents apoptotic induction by limiting accumulation of phosphorylated active forms of the stress kina...

MADS box transcription factors control diverse developmental processes in plants, metazoans, and fungi. To analyze the involvement of MADS box proteins in fruiting body development of filamentous ascomycetes, we isolated the mcm1 gene from the homothallic ascomycete Sordaria macrospora, which encodes a putative homologue of the Saccharomyces cerevisiae MADS box protein Mcm1p. Deletion of the S....

AIMS Myocardial tumour necrosis factor-α (TNF-α) expression induces cardiac dysfunction in endotoxemia. The aim of this study was to investigate the role of mitogen-activated protein kinase phosphatase-1 (MKP1) pathway in myocardial TNF-α expression and cardiac function during endotoxemia. METHODS AND RESULTS Lipopolysaccharide (LPS) increased MKP1 expression in the myocardium in vivo and in ...

The elucidation of chemoresistance mechanisms is important to improve cancer patient survival. In this report, we investigated the role and mechanism through which receptor-interacting protein 1 (RIP1), a mediator in cell survival and death signaling, participates in cancer's response to chemotherapy. In lung cancer cells, knockdown of RIP1 substantially increased cisplatin-induced apoptotic cy...

Limited information is available on the role of MAPK phosphatase 1 (MKP1) signaling in osteoblasts. We have recently reported distinct roles for MKP1 during osteoblast proliferation, differentiation, and skeletal responsiveness to parathyroid hormone (PTH). As MKP1 regulates the phosphorylation status of MAPKs, we investigated the involvement of P-ERK and P-p38 MAPKs in MKP1 knockout (KO) early...

We have previously demonstrated that mitogen-activated protein kinase phosphatase 1, Mkp1, is expressed in the developing and rat adult substantia nigra and striatum, where it promotes the growth of nigral dopaminergic neurons. Mkp1 may therefore have therapeutic potential for Parkinson's disease. In the present study, we have assessed the expression of Mkp1 and TH in the substantia nigra and s...

The tumor suppressor p53 protein suppresses cell growth by inducing cell cycle arrest or apoptosis. Despite the fact that p53-dependent p21-mediated G1 arrest induced by DNA damage is well defined, the role of p53 in the cell cycle in response to the MAKP signaling remains to be determined. Here we show that MKP1, a member of the dual specificity protein phosphatase family capable of inactivati...