Interferon-stimulated gene 20 kDa protein (ISG20)
The protein contains 181 amino acids for an estimated molecular weight of 20363 Da.
Interferon-induced antiviral exoribonuclease that acts on single-stranded RNA and also has minor activity towards single-stranded DNA. Exhibits antiviral activity against RNA viruses including hepatitis C virus (HCV), hepatitis A virus (HAV) and yellow fever virus (YFV) in an exonuclease-dependent manner. May also play additional roles in the maturation of snRNAs and rRNAs, and in ribosome biogenesis. (updated: April 1, 2015)
Protein identification was indicated in the following studies:
- Goodman and co-workers. (2013) The proteomics and interactomics of human erythrocytes. Exp Biol Med (Maywood) 238(5), 509-518.
- Hegedűs and co-workers. (2015) Inconsistencies in the red blood cell membrane proteome analysis: generation of a database for research and diagnostic applications. Database (Oxford) 1-8.
- Bryk and co-workers. (2017) Quantitative Analysis of Human Red Blood Cell Proteome. J Proteome Res. 16(8), 2752-2761.
- D'Alessandro and co-workers. (2017) Red blood cell proteomics update: is there more to discover? Blood Transfus. 15(2), 182-187.
Methods
The following articles were analysed to gather the proteome content of erythrocytes.
The gene or protein list provided in the studies were processed using the ID mapping API of Uniprot in September 2018. The number of proteins identified and mapped without ambiguity in these studies is indicated below.
Only Swiss-Prot entries (reviewed) were considered for protein evidence assignation.
| Publication | Identification 1 | Uniprot mapping 2 | Not mapped / Obsolete | TrEMBL | Swiss-Prot |
|---|---|---|---|---|---|
| Goodman (2013) | 2289 (gene list) | 2278 | 53 | 20599 | 2269 |
| Lange (2014) | 1234 | 1234 | 7 | 28 | 1224 |
| Hegedus (2015) | 2638 | 2622 | 0 | 235 | 2387 |
| Wilson (2016) | 1658 | 1528 | 170 | 291 | 1068 |
| d'Alessandro (2017) | 1826 | 1817 | 2 | 0 | 1815 |
| Bryk (2017) | 2090 | 2060 | 10 | 108 | 1942 |
| Chu (2018) | 1853 | 1804 | 55 | 362 | 1387 |
1 as available in the article and/or in supplementary material
2 uniprot mapping returns all protein isoforms as one entry
The compilation of older studies can be retrieved from the Red Blood Cell Collection database.
The data and differentiation stages presented below come from the proteomic study and analysis performed by our partners of the GReX consortium, more details are available in their published work.
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Biological Process
Cell population proliferation
Cytokine-mediated signaling pathway
Defense response to virus
DNA catabolic process, exonucleolytic
Negative regulation of viral genome replication
Response to virus
RNA catabolic process
RNA phosphodiester bond hydrolysis, exonucleolytic
RRNA processing
Type I interferon signaling pathway
The reference OMIM entry for this protein is 604533
Interferon-stimulated gene, 20-kd; isg20
Hem45
Binding of interferons (see IFNA, 147660; IFNB, 147570) to their specific cell surface receptors triggers the rapid nuclear translocation of a complex formed by association between the various phosphorylated STAT (see 600555) proteins. This results in the induction of genes that mediate the biologic functions of IFNs which may be localized in the cytoplasm, nucleus, or cell surface. The nuclear proteins may localize within the nucleolus or within the nuclear matrix, specifically to nuclear bodies (NBs) or PML (promyelocytic leukemia; 102578) NBs. Proteins of various oncogenic viruses have been found to associate with and disrupt PML NBs. In addition, PML, SP100 (604585), and NDP52 (604587) are inducible by IFN. By screening an IFN-treated Daudi cell cDNA library, Gongora et al. (1997) obtained a cDNA encoding a deduced 179-amino acid, 20-kD, basic (pI 9.2) interferon-induced protein, termed ISG20, containing 7 lysine and 19 arginine residues. Sequence analysis of ISG20 also predicted a coiled-coil structure in the region of amino acids 78-107, suggesting that the protein could be a component of a multiprotein complex. The coiled-coil domain is bordered on both sides by potential phosphorylation sites. ISG20 shares amino acid cluster homologies with XPMC2H (602930), suggesting an antigrowth function, which is also a property of IFNs. On the basis of the lysine- and arginine-rich domains of ISG20, Gongora et al. (1997) suspected nuclear targeting. Using laser confocal immunofluorescence, they found speckled nuclear staining with colocalization of ISG20, PML, and SP100. Northern blot analysis of IFN-treated Daudi cells determined that expression increases in response to this stimulus and occurs at the transcriptional level. In the absence of IFN treatment, Northern blot analysis detected ISG20 expression in peripheral blood leukocytes, thymus, spleen, colon, and lung. By use of differential display-PCR and mRNA from a human cervical cell line, Pentecost (1998) identified a cDNA encoding a 181-amino acid protein, which they termed HEM45. HEM45 aligns with the C-terminal half of XPMC2H. The authors found that HEM45 mRNA expression increases in response to estrogen in estrogen receptor-expressing cells in the presence of cycloheximide. By radiolabeled probe in situ hybridization, Mattei et al. (1997) mapped the ISG20 gene to 15q26. ... More on the omim web site
Feb. 2, 2018: Protein entry updated
Automatic update: Uniprot description updated
Dec. 19, 2017: Protein entry updated
Automatic update: Uniprot description updated
Nov. 23, 2017: Protein entry updated
Automatic update: Uniprot description updated
March 16, 2016: Protein entry updated
Automatic update: OMIM entry 604533 was added.
Jan. 28, 2016: Protein entry updated
Automatic update: model status changed
Jan. 24, 2016: Protein entry updated
Automatic update: model status changed