Source:http://linkedlifedata.com/resource/umls/id/C0035684
MSH: Post-transcriptional biological modification of messenger, transfer, or ribosomal RNAs or their precursors. It includes cleavage, methylation, thiolation, isopentenylation, pseudouridine formation, conformational changes, and association with ribosomal protein.,CSP: any alterations made to primary RNA transcripts before leaving the nucleus as mature mRNA; e.g., removing of introns, splicing of exons, addition of cap or a poly-A tail.