RESUMO
Nonsense-mediated mRNA decay (NMD) is a highly regulated quality control mechanism through which mRNAs harboring a premature termination codon are degraded. It is also a regulatory pathway for some genes. This mechanism is subject to various levels of regulation, including phosphorylation. To date only one kinase, SMG1, has been described to participate in NMD, by targeting the central NMD factor UPF1. Here, screening of a kinase inhibitor library revealed as putative NMD inhibitors several molecules targeting the protein kinase AKT1. We present evidence demonstrating that AKT1, a central player in the PI3K/AKT/mTOR signaling pathway, plays an essential role in NMD, being recruited by the UPF3X protein to phosphorylate UPF1. As AKT1 is often overactivated in cancer cells and as this should result in increased NMD efficiency, the possibility that this increase might affect cancer processes and be targeted in cancer therapy is discussed.
Assuntos
Códon sem Sentido , Degradação do RNAm Mediada por Códon sem Sentido , Proteínas Proto-Oncogênicas c-akt/genética , RNA Helicases/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Transativadores/genética , Proliferação de Células , Fator de Iniciação 4E em Eucariotos/genética , Fator de Iniciação 4E em Eucariotos/metabolismo , Biblioteca Gênica , Genes Reporter , Células HEK293 , Células HeLa , Humanos , Luciferases/genética , Luciferases/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Helicases/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Transativadores/metabolismoRESUMO
The Open Microscopy Environment Remote Objects (OMERO) is an open-source image manager used by many biologists to store, organize, view, and share microscopy images, while the open-source software ImageJ/Fiji is a very popular program used to analyse them. However, there is a lack of an easy-to-use generic tool to run a workflow on a batch of images without having to download them to local computers, and to automatically organize the results in OMERO. To offer this functionality, we have built (i) a library in Java: "Simple OMERO Client", to communicate with an OMERO database from Java software, (ii) an ImageJ/Fiji plugin to run a macro-program on a batch of images from OMERO and (iii) a new set of Macro Functions, "OMERO Macro extensions", dedicated to interact with OMERO in macro-programming. The latter is intended for developers, with additional possibilities using tag criteria, while the "Batch OMERO plugin" is more geared towards non-IT scientists and has a very easy to use interface. Each tool is illustrated with a use case.