60S ribosomal protein L22 explained

60S ribosomal protein L22 is a protein that in humans is encoded by the RPL22 gene on Chromosome 1.^{[1] [2]}

Function

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a cytoplasmic ribosomal protein that is a component of the 60S subunit. The protein belongs to the L22E family of ribosomal proteins. Its initiating methionine residue is post-translationally removed. The protein can bind specifically to Epstein–Barr virus-encoded small RNA (EBER) 1. The mouse protein has been shown to be capable of binding to heparin. Transcript variants utilizing alternative polyA signals exist. As is typical for genes encoding ribosomal proteins, there are multiple processed pseudogenes of this gene dispersed through the genome. It was previously thought that this gene mapped to 3q26 and that it was fused to the acute myeloid leukemia 1 (AML1) gene located at 21q22 in some therapy-related myelodysplastic syndrome patients with 3;21 translocations; however, these fusions actually involve a ribosomal protein L22 pseudogene located at 3q26, and this gene actually maps to 1p36.3-p36.2.^[2]

Insects

The gene may play a role in Insect toxicity resistance. In culex mosquitos, it was one of several ribosomal proteins which were overexpressed in strains resistant to the insecticide deltamethrin.^[3] More focused analysis revealed that resistant mosquitoes expressed RPL22 at a level more than 2.5x higher than susceptible strains; however, the same study found that over-expression of RPL22 in transfected cells caused a down-regulation of a different deltamethrin-resistance gene (CYP6A1) and made these cells overall less resistant to the insecticide.^[4]

Further reading

• Wool IG, Chan YL, Glück A . Structure and evolution of mammalian ribosomal proteins . Biochemistry and Cell Biology . 73 . 11–12 . 933–47 . 1996 . 8722009 . 10.1139/o95-101 .
• Toczyski DP, Steitz JA . EAP, a highly conserved cellular protein associated with Epstein-Barr virus small RNAs (EBERs) . The EMBO Journal . 10 . 2 . 459–66 . February 1991 . 1846807 . 452667 . 10.1002/j.1460-2075.1991.tb07968.x.
• Fujita Y, Okamoto T, Noshiro M, McKeehan WL, Crabb JW, Whitney RG, Kato Y, Sato JD, Takada K . A novel heparin-binding protein, HBp15, is identified as mammalian ribosomal protein L22 . Biochemical and Biophysical Research Communications . 199 . 2 . 706–13 . March 1994 . 8135813 . 10.1006/bbrc.1994.1286 .
• Toward a complete human genome sequence . Genome Research . 8 . 11 . 1097–108 . November 1998 . 9847074 . 10.1101/gr.8.11.1097 . Sanger Centre . The . Washington University Genome Sequencing Cente . The . free .
• Le S, Sternglanz R, Greider CW . Identification of two RNA-binding proteins associated with human telomerase RNA . Molecular Biology of the Cell . 11 . 3 . 999–1010 . March 2000 . 10712515 . 14826 . 10.1091/mbc.11.3.999 .
• Shu-Nu C, Lin CH, Lin A . An acidic amino acid cluster regulates the nucleolar localization and ribosome assembly of human ribosomal protein L22 . FEBS Letters . 484 . 1 . 22–8 . October 2000 . 11056215 . 10.1016/S0014-5793(00)02118-9 . 17840004 . free .
• Uechi T, Tanaka T, Kenmochi N . A complete map of the human ribosomal protein genes: assignment of 80 genes to the cytogenetic map and implications for human disorders . Genomics . 72 . 3 . 223–30 . March 2001 . 11401437 . 10.1006/geno.2000.6470 .
• Andersen JS, Lyon CE, Fox AH, Leung AK, Lam YW, Steen H, Mann M, Lamond AI . Directed proteomic analysis of the human nucleolus . Current Biology . 12 . 1 . 1–11 . January 2002 . 11790298 . 10.1016/S0960-9822(01)00650-9 . 14132033 . free . 2002CBio...12....1A .
• Yoshihama M, Uechi T, Asakawa S, Kawasaki K, Kato S, Higa S, Maeda N, Minoshima S, Tanaka T, Shimizu N, Kenmochi N . The human ribosomal protein genes: sequencing and comparative analysis of 73 genes . Genome Research . 12 . 3 . 379–90 . March 2002 . 11875025 . 155282 . 10.1101/gr.214202 .
• Andersen JS, Lam YW, Leung AK, Ong SE, Lyon CE, Lamond AI, Mann M . Nucleolar proteome dynamics . Nature . 433 . 7021 . 77–83 . January 2005 . 15635413 . 10.1038/nature03207 . 2005Natur.433...77A . 4344740 .
• Chen KC, Chiang HS, Fang CL . EBER expression of pure urinary bladder lymphoepithelioma-like carcinoma in two unique Asian patients . Urologia Internationalis . 74 . 3 . 280–2 . 2005 . 15812220 . 10.1159/000083565 . 24326120 .
• Fok V, Mitton-Fry RM, Grech A, Steitz JA . Multiple domains of EBER 1, an Epstein-Barr virus noncoding RNA, recruit human ribosomal protein L22 . RNA . 12 . 5 . 872–82 . May 2006 . 16556938 . 1440895 . 10.1261/rna.2339606 .
• Nakao K, Mochiki M, Nibu K, Sugasawa M, Uozaki H . Analysis of prognostic factors of nasopharyngeal carcinoma: impact of in situ hybridization for Epstein-Barr virus encoded small RNA 1 . Otolaryngology–Head and Neck Surgery . 134 . 4 . 639–45 . April 2006 . 16564389 . 10.1016/j.otohns.2005.11.022 . 29788079 .

Notes and References

1. Nucifora G, Begy CR, Erickson P, Drabkin HA, Rowley JD . The 3;21 translocation in myelodysplasia results in a fusion transcript between the AML1 gene and the gene for EAP, a highly conserved protein associated with the Epstein-Barr virus small RNA EBER 1 . Proceedings of the National Academy of Sciences of the United States of America . 90 . 16 . 7784–8 . August 1993 . 8395054 . 47227 . 10.1073/pnas.90.16.7784 . 1993PNAS...90.7784N . free .
2. Web site: Entrez Gene: RPL22 ribosomal protein L22.
3. Wu . Hai-Wei . Tian . Hai-Sheng . Wu . Guan-Ling . Langdon . Gretchen . Kurtis . Jonathan . Shen . Bo . Ma . Lei. Li. Xiu-Lan. Gu. Yan. Hu. Xiao-Bang. Zhu. Chang-Liang . vanc . Culex pipiens pallens: identification of genes differentially expressed in deltamethrin-resistant and -susceptible strains. Pesticide Biochemistry and Physiology . July 2004 . 79 . 3 . 75–83 . 10.1016/j.pestbp.2004.04.004 .
4. He J, Sun H, Zhang D, Sun Y, Ma L, Chen L, Liu Z, Xiong C, Yan G, Zhu C . Cloning and characterization of 60S ribosomal protein L22 (RPL22) from Culex pipiens pallens . Comparative Biochemistry and Physiology. Part B, Biochemistry & Molecular Biology . 153 . 2 . 216–22 . June 2009 . 19298862 . 10.1016/j.cbpb.2009.03.003 . 5058277 .