Among the 67 proteins that interact with RBMX protein, the splicing factor hnRNP A1 was of particular interest because hnRNP A1 had a higher MS score among our identified splicing regulators (Supplementary Fig. 3A, B, Supplementary Table 1) and is the key regulator of PKM pre-mRNA alternative splicing in cancer [24]. The gene discussed is PKM; the disease is cancer.