RNPA_THET8 Protein C5 MDEKDVATQPQETGQNPRLSGQDEDPGRPEGAEAPPSEGALAPHARRSEAVGPKPPAPGGKLLSLKGDRAFQRLRKGRAGRGRYVSVKWLPAAELRVGIVVSKKVGKAVVRNKVKRRLREILRRLHLPQAHLLVVASPEAREADFAELFRDVVRALRKSGLVQ TTHA0445 rnpA Ribonuclease P protein component 163 RNaseP catalyzes the removal of the 5'-leader sequence from pre-tRNA to produce the mature 5'-terminus. It can also cleave other RNA substrates such as 4.5S RNA. The protein component plays an auxiliary but essential role in vivo by binding to the 5'-leader sequence and broadening the substrate specificity of the ribozyme.