Human colon cancer HCT116 cell LC MSMS

Mitosis deregulation is a key event during carcinogenesis. Alternative splicing spectrum alteration plays a critical role during mitosis shift. However, the molecules responsible for dysregulated alternative splicing driving carcinogenetic mitosis remain poorly defined. Here, we demonstrate that cancer metastasis-associated antigen 1 (MTA1), a well-known oncogenic chromatin modifier, broadly interacts and co-expresses with RBPs across cancers, contributes to cancerous mitosis-related alternative splicing. Using developed fCLIP-seq technology, we show that MTA1 binds abundant transcripts, preferentially at splicing-responsible motifs, influencing both the abundance and alternative splicing (AS) of target transcripts. MTA1 is cytoplasmic and extrachromosomal at mitosis. Through the RNA-association activity,