The pseudophosphatase MK-STYX physically and genetically interacts with the mitochondrial phosphatase PTPMT1
| العنوان: | The pseudophosphatase MK-STYX physically and genetically interacts with the mitochondrial phosphatase PTPMT1 |
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| المؤلفون: | Jeffrey P. MacKeigan, Juliana L. Sacoman, L. Alex Gaither, Natalie M. Niemi, Laura M. Westrate, Nathan J. Lanning, Katie R. Martin |
| المصدر: | PLoS ONE, Vol 9, Iss 4, p e93896 (2014) PLoS ONE |
| بيانات النشر: | Public Library of Science (PLoS), 2014. |
| سنة النشر: | 2014 |
| مصطلحات موضوعية: | Proteomics, lcsh:Medicine, Apoptosis, Mitochondrion, Biochemistry, chemistry.chemical_compound, 0302 clinical medicine, Cell Signaling, RNA interference, Molecular Cell Biology, Cardiolipin, Enzyme Chemistry, lcsh:Science, Cellular Stress Responses, 0303 health sciences, Gene knockdown, Multidisciplinary, Cell Death, Cytochrome c, Mechanisms of Signal Transduction, Cell biology, Enzymes, Mitochondria, Cell Processes, 030220 oncology & carcinogenesis, RNA Interference, Cellular Structures and Organelles, Research Article, Signal Transduction, Programmed cell death, Phosphatase, Biology, Enzyme Regulation, 03 medical and health sciences, Genetics, Humans, Protein kinase A, Protein Interactions, 030304 developmental biology, Oncogenic Signaling, lcsh:R, PTEN Phosphohydrolase, Biology and Life Sciences, Proteins, Cell Biology, Lipid Metabolism, chemistry, biology.protein, Enzymology, lcsh:Q, Gene Function, Apoptosis Regulatory Proteins, HeLa Cells |
| الوصف: | We previously performed an RNA interference (RNAi) screen and found that the knockdown of the catalytically inactive phosphatase, MK-STYX [MAPK (mitogen-activated protein kinase) phospho-serine/threonine/tyrosine-binding protein], resulted in potent chemoresistance. Our follow-up studies demonstrated that knockdown of MK-STYX prevents cells from undergoing apoptosis through a block in cytochrome c release, but that MK-STYX does not localize proximal to the molecular machinery currently known to control this process. In an effort to define its molecular mechanism, we utilized an unbiased proteomics approach to identify proteins that interact with MK-STYX. We identified the mitochondrial phosphatase, PTPMT1 (PTP localized to mitochondrion 1), as the most significant and unique interaction partner of MK-STYX. We previously reported that knockdown of PTPMT1, an important component of the cardiolipin biosynthetic pathway, is sufficient to induce apoptosis and increase chemosensitivity. Accordingly, we hypothesized that MK-STYX and PTPMT1 interact and serve opposing functions in mitochondrial-dependent cell death. We confirmed that MK-STYX and PTPMT1 interact in cells and, importantly, found that MK-STYX suppresses PTPMT1 catalytic activity. Furthermore, we found that knockdown of PTPMT1 resensitizes MK-STYX knockdown cells to chemotherapeutics and restores the ability to release cytochrome c. Taken together, our data support a model in which MK-STYX controls apoptosis by negatively regulating PTPMT1. Given the important role of PTPMT1 in the production of cardiolipin and other phospholipids, this raises the possibility that dysregulated mitochondrial lipid metabolism may facilitate chemoresistance. |
| اللغة: | English |
| تدمد: | 1932-6203 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c018b5ec3de5148296a4704ad6a42111Test http://europepmc.org/articles/PMC3977970?pdf=renderTest |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....c018b5ec3de5148296a4704ad6a42111 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 19326203 |
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