Component of ribonuclease P, a ribonucleoprotein complex that generates mature tRNA molecules by cleaving their 5'-ends (PubMed:12003489, PubMed:16723659, PubMed:30454648). Also a component of the MRP ribonuclease complex, which cleaves pre-rRNA sequences (PubMed:28115465). Component of nuclear RNase P and RNase MRP ribonucleoproteins (PubMed:12003489, PubMed:15096576, PubMed:16723659, PubMed:20215441, PubMed:28115465, PubMed:30454648). RNase P consists of a catalytic RNA moiety and 10 different protein chains; POP1, POP4, POP5, POP7, RPP14, RPP21, RPP25, RPP30, RPP38 and RPP40 (PubMed:12003489, PubMed:16723659, PubMed:20215441, PubMed:30454648). Within the RNase P complex, POP1, POP7 and RPP25 form the 'finger' subcomplex, POP5, RPP14, RPP40 and homodimeric RPP30 form the 'palm' subcomplex, and RPP21, POP4 and RPP38 form the 'wrist' subcomplex. All subunits of the RNase P complex interact with the catalytic RNA (PubMed:30454648). Several subunits of RNase P are also part of the RNase MRP complex. RNase MRP consists of a catalytic RNA moiety and about 8 protein subunits; POP1, POP7, RPP25, RPP30, RPP38, RPP40 and possibly also POP4 and POP5 (PubMed:15096576, PubMed:16723659, PubMed:28115465). POP7 forms a heterodimer with RPP25 that binds to the P3 stem loop of the catalytic RNA (PubMed:20215441, PubMed:29625199). Belongs to the histone-like Alba family.