The function of MRPL45 (mitochondrial ribosomal protein L45, Ensembl gene identifier ENSG00000278845) is as follows. Component of the mitochondrial large ribosomal subunit (mt- LSU) (PubMed:25278503, PubMed:25838379, PubMed:28892042, PubMed:33602856, PubMed:35177605). Within the mitochondrial ribosomes, required to direct the nascent polypeptide toward the tunnel exit and position the exit at a distance from the membrane surface (PubMed:33602856). {ECO:0000269|PubMed:25278503, ECO:0000269|PubMed:25838379, ECO:0000269|PubMed:28892042, ECO:0000269|PubMed:33602856, ECO:0000269|PubMed:35177605}.