RSRP1 (arginine and serine rich protein 1) is a spliceosomal factor involved in pre-mRNA processing and isoform regulation. The protein localizes to the nucleus where it contributes to spliceosome assembly and regulates alternative splicing of target genes including PARP6 1. RSRP1 functions as part of the RNA metabolism and gene expression machinery, with its expression levels potentially affected by epigenetic modifications during aging 2. In terms of mechanism, RSRP1 expression is altered downstream of splicing factor degradation; when the critical splicing regulator RBM39 is depleted, RSRP1 is upregulated, demonstrating its role in compensatory splicing responses 3. Disease relevance emerges from rheumatoid arthritis (RA) studies, where RSRP1 is specifically downregulated in double-negative T cells from RA patients, correlating with defects in oxidative phosphorylation and antigen presentation 4. This downregulation in immune cells suggests RSRP1 may contribute to the immunological dysfunction characteristic of RA. While RSRP1's precise clinical significance remains incompletely characterized, its dysregulation in both inflammatory autoimmune disease and its role in splicing-dependent protein isoform switching position it as a potential biomarker and therapeutic target in RA and possibly other conditions involving splicing dysregulation.