To gain further insights into the post-transcriptional regulation process in the male sexual stage of Plasmodium, we focused on RBPm1, the most specifically expressed RNA-binding protein in the male gametocyte of P. yoelii, for in-depth investigation. In the first part of this study, we identified RBPm1 as a splicing activator, facilitating the splicing of 30 introns among 26 genes in the male gametocytes. Next, we sought to elucidate how RBPm1 exerts its splicing-promoting function. To achieve this, we performed biotin-based proximity labeling experiments on RBPm1, identifying 113 proteins that interact with RBPm1. Among these proteins, all 13 subunits of the spliceosome E complex were present, while other components of the splicing cycle were not significantly enriched. This suggests that RBPm1 participates in the initiation step of RNA splicing by interacting with the E-complex to promote intron splicing.