mRNA turnover protein 4 homolog (MRTO4) is a member of the ribosomal protein L10P family. MRTO4 is a protein sharing a low level of sequence similarity with ribosomal protein P0. Though the precise function of the MRTO4 is presently unknown, it seems to be involved in mRNA turnover and ribosome assembly. MRTO4 is a nucleolar component of the ribosome assembly apparatus which shares remarkable similarity and contends for binding to the 25S rRNA GAR domain with the ribosomal protein P0. The MRTO4 gene is located on human chromosome 1, which extends over 260 million base pairs, is comprised of over 3,000 genes and contains approximately 8% of the human genome.