Multifunctional RNA-binding protein that recognizes the K-turn motif in ribosomal RNA, the RNA component of RNase P, box H/ACA, box C/D and box C'/D' sRNAs (By similarity). Part of ribonuclease P, a protein complex that generates mature tRNA molecules by cleaving their 5'-ends, this subunit dramatically stimulates RNase P activity. Endonucleolytic cleavage of RNA, removing 5'-extranucleotides from tRNA precursor. kcat 10 min(-1) in absence of L7Ae, 63 min(-1) in presence of L7Ae. Kinetic parameters determined at 37 degrees Celsius. Optimum temperature is 36-38 degrees Celsius in the absence of L7Ae, 48-50 degrees Celsius in presence of L7Ae. Part of the 50S ribosomal subunit. Part of the RNase P complex. Belongs to the eukaryotic ribosomal protein eL8 family.