DUX4 interactors by LC-MSMS

The aim of this study is to define the molecular mechanisms underlying DUX4-associated toxicity in the context of facioscapulohumeral muscular dystrophy (FSHD). DUX4 is a transcription factor, which induces cell death by activating the transcription of its targets. No molecule able to directly control DUX4 activity is currently known. By using a tandem affinity purification protocol combined to mass spectrometry analysis, we identified Matrin 3 (MATR3), as the first cellular factor able to directly block DUX4 toxic activity. We found that MATR3 binds to the DNA binding domain of DUX4 blocking the activation of its genomic targets.