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Online Mendelian Inheritance in Man (OMIM)

  • ️Mon Feb 04 2002

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UBIQUITIN A-52-RESIDUE RIBOSOMAL PROTEIN FUSION PRODUCT; UBA52

Alternative titles; symbols

HUMAN UBIQUITIN CARBOXYL EXTENSION PROTEIN, 52-RESIDUE; HUBCEP52
UBCEP, 52-AMINO ACID; CEP52
RIBOSOMAL PROTEIN L40; RPL40

HGNC Approved Gene Symbol: UBA52

Cytogenetic location: 19p13.11 Genomic coordinates (GRCh38) : 19:18,563,766-18,577,550 (from NCBI)

TEXT

Description

Ubiquitin is a small protein of 76 amino acids that is found exclusively in eukaryotes and shows extreme evolutionary conservation. Comparison of ubiquitin sequences from species ranging from yeast to human shows that 71 of the 76 residues are conserved. The human genome contains multiple ubiquitin genes, many of which are nonfunctional reverse-transcribed pseudogenes. The transcriptionally active genes generate mRNAs of approximately 600, 1,000, and 2,500 nucleotides, and these have been termed UBA, UBB (191339), and UBC (191340), respectively. The 600-nucleotide UBA transcripts encode human ubiquitin-ribosomal protein fusion proteins and represent products of the UBA52 gene (Baker and Board, 1991) and the UBA80 gene (191343; Lund et al., 1985).

Cloning and Expression

By screening a placental cDNA library with the tail-like region of the EHD5 pseudogene as probe, Baker and Board (1991) isolated a cDNA encoding a ubiquitin moiety followed by a 52-amino acid tail, which they termed UBA52. UBA52 is 81% identical to yeast Ubi1/Ubi2 and shares conserved cysteine residues. Northern blot analysis revealed expression in lymphocytes and placenta.

Gene Structure

By genomic sequence analysis, Baker and Board (1991) determined that the UBA52 gene contains 5 exons and spans more than 2 kb. The promoter is located in a CpG-rich island, has SP1-binding sites, and lacks a TATA motif, suggesting a structurally typical ribosomal protein gene.

Mapping

Because of the relatively large number of ubiquitin pseudogenes, special strategies are necessary to map the functional genes. Webb et al. (1994) used an intron sequence to localize the UBA52 ubiquitin-ribosomal protein fusion gene. Analysis of somatic cell hybrids containing individual human chromosomes indicated that the UBA52 gene is located on chromosome 19. In situ hybridization studies confirmed the chromosomal localization but showed 2 peaks of hybridization: a major one over 19p13.1-p12 and a secondary one over 19q12-q13.11. Since the peak of hybridization over the short arm was consistently the strongest in 5 individuals, Webb et al. (1994) considered it likely that this is the localization of the UBA52 gene.

REFERENCES

  1. Baker, R. T., Board, P. G. The human ubiquitin-52 amino acid fusion protein gene shares several structural features with mammalian ribosomal protein genes. Nucleic Acids Res. 19: 1035-1040, 1991. [PubMed: 1850507] [Full Text: https://doi.org/10.1093/nar/19.5.1035]

  2. Lund, P. K., Moats-Staats, B. M., Simmons, J. G., Hoyt, E., D'Ercole, A. J., Martin, F., Van Wyk, J. J. Nucleotide sequence analysis of a cDNA encoding human ubiquitin reveals that ubiquitin is synthesized as a precursor. J. Biol. Chem. 260: 7609-7613, 1985. [PubMed: 2581967]

  3. Webb, G. C., Baker, R. T., Coggan, M., Board, P. G. Localization of the human UBA52 ubiquitin fusion gene to chromosome band 19p13.1-p12. Genomics 19: 567-569, 1994. [PubMed: 8188300] [Full Text: https://doi.org/10.1006/geno.1994.1108]

Contributors:

Paul J. Converse - updated : 2/4/2002

Creation Date:

Victor A. McKusick : 3/26/1994

Edit History:

carol : 11/03/2003
mgross : 2/4/2002
terry : 2/4/2002
mgross : 9/13/2001
joanna : 9/12/2001
mgross : 9/6/2001
carol : 3/26/1994