Mitochondrial ribosomal protein L39 explained

39S ribosomal protein L39, mitochondrial is a protein that in humans is encoded by the MRPL39 gene.^[1]

Mammalian mitochondrial ribosomal proteins are encoded by nuclear genes and help in protein synthesis within the mitochondrion. Mitochondrial ribosomes (mitoribosomes) consist of a small 28S subunit and a large 39S subunit. They have an estimated 75% protein to rRNA composition compared to prokaryotic ribosomes, where this ratio is reversed. Another difference between mammalian mitoribosomes and prokaryotic ribosomes is that the latter contain a 5S rRNA. Among different species, the proteins comprising the mitoribosome differ greatly in sequence, and sometimes in biochemical properties, which prevents easy recognition by sequence homology. This gene encodes a 39S subunit protein. Two transcript variants encoding distinct isoforms have been described. A pseudogene corresponding to this gene is found on chromosome 5q.^[2]

Further reading

• Maruyama K, Sugano S . Oligo-capping: a simple method to replace the cap structure of eukaryotic mRNAs with oligoribonucleotides . Gene . 138 . 1–2 . 171–4 . 1994 . 8125298 . 10.1016/0378-1119(94)90802-8 .
• Suzuki Y, Yoshitomo-Nakagawa K, Maruyama K, etal . Construction and characterization of a full length-enriched and a 5'-end-enriched cDNA library . Gene . 200 . 1–2 . 149–56 . 1997 . 9373149 . 10.1016/S0378-1119(97)00411-3 .
• O'Brien TW, Fiesler SE, Denslow ND, etal . Mammalian mitochondrial ribosomal proteins (2). Amino acid sequencing, characterization, and identification of corresponding gene sequences . J. Biol. Chem. . 274 . 51 . 36043–51 . 2000 . 10593885 . 10.1074/jbc.274.51.36043 . free .
• Spirina O, Bykhovskaya Y, Kajava AV, etal . Heart-specific splice-variant of a human mitochondrial ribosomal protein (mRNA processing; tissue specific splicing) . Gene . 261 . 2 . 229–34 . 2001 . 11167009 . 10.1016/S0378-1119(00)00504-7 .
• O'Brien TW . Evolution of a protein-rich mitochondrial ribosome: implications for human genetic disease . Gene . 286 . 1 . 73–9 . 2002 . 11943462 . 10.1016/S0378-1119(01)00808-3 .
• Strausberg RL, Feingold EA, Grouse LH, etal . Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences . Proc. Natl. Acad. Sci. U.S.A. . 99 . 26 . 16899–903 . 2003 . 12477932 . 10.1073/pnas.242603899 . 139241 . 2002PNAS...9916899M . free .
• Zhang Z, Gerstein M . Identification and characterization of over 100 mitochondrial ribosomal protein pseudogenes in the human genome . Genomics . 81 . 5 . 468–80 . 2003 . 12706105 . 10.1016/S0888-7543(03)00004-1 .
• Ota T, Suzuki Y, Nishikawa T, etal . Complete sequencing and characterization of 21,243 full-length human cDNAs . Nat. Genet. . 36 . 1 . 40–5 . 2004 . 14702039 . 10.1038/ng1285 . free .
• Gerhard DS, Wagner L, Feingold EA, etal . The Status, Quality, and Expansion of the NIH Full-Length cDNA Project: The Mammalian Gene Collection (MGC) . Genome Res. . 14 . 10B . 2121–7 . 2004 . 15489334 . 10.1101/gr.2596504 . 528928 .

Notes and References

1. Kenmochi N, Suzuki T, Uechi T, Magoori M, Kuniba M, Higa S, Watanabe K, Tanaka T . The human mitochondrial ribosomal protein genes: mapping of 54 genes to the chromosomes and implications for human disorders . Genomics . 77 . 1–2 . 65–70 . Sep 2001 . 11543634 . 10.1006/geno.2001.6622 .
2. Web site: Entrez Gene: MRPL39 mitochondrial ribosomal protein L39.