Mitochondrial ribosomal protein of the large subunit%3B located in close proximity to the polypeptide exit channel of the ribosome%3B mutations in human homolog MRPL44 cause childhood cardiomyopathy%3B human MRPL44 deficiency results in inefficient assembly of the mitochondrial ribosome%2C and in tissue-specific respiratory chain deficiency%2C manifesting as either Complex I+Complex IV or Complex IV deficiency%2C depending on a cell type