The RNA recognition motif (RRM) is found approximately in all lifekingdoms and is one of the most abundant protein domains. RRM-containingproteins take part in post transcriptional events such as: pre-mRNA processing,splicing, alternative splicing, mRNA stability, mRNA export, RNA editing, andtranslation regulation. My M.Sc. project focuses on RNA-binding motif 42(RBM42) that contains one RRM motif at its C-terminal region. Unpublished workfrom our lab implicated RBM42 in RNA splicing and DNA damage response (DDR) bya yet unknown mechanism. In an attempt to shed molecular insights into how RBM42regulates splicing and DNA repair, we sought to map RBM42 interactome using ascorbateperoxidase (APEX2)-based proximity labelling approach combined with MassSpectrometry. Toward this end, we used CRISPR-cas9 methodology to knock-inAPEX2 to the C-terminal of the endogenous RBM42. RBM42 proximal proteins werebiotinylated by APEX2 activation using H2O2 and subjectedto Mass spectrometry. Interactome analysis substantiates RBM42 role in mRNA splicing andDNA damage repair and revealed unexpected pathways that are regulated by RBM42such as protein synthesis. During the seminar, I will elaborate on how RBM42interactome advances our understanding of RBM42 biological functions.