The function of RPP38 (ribonuclease P/MRP subunit p38, Ensembl gene identifier ENSG00000152464) is as follows. Component of ribonuclease P, a ribonucleoprotein complex that generates mature tRNA molecules by cleaving their 5'-ends (PubMed:10444065, PubMed:30454648, PubMed:9037013, PubMed:9630247). Also a component of the MRP ribonuclease complex, which cleaves pre- rRNA sequences (PubMed:28115465). {ECO:0000269|PubMed:10444065, ECO:0000269|PubMed:28115465, ECO:0000269|PubMed:30454648, ECO:0000269|PubMed:9037013, ECO:0000269|PubMed:9630247}.