UniProt Accession

 ISG15_MOUSE; Q64339; Q8K0H3 

Genbank Protein ID

 X56602; U58202; BC031424; BC083156 

Genbank Nucleotide ID

 CAA39939.1; AAB02697.1; AAH31424.1; AAH83156.1 

Protein Name

 Ubiquitin-like protein ISG15 

Protein Synonyms/Alias

 Interferon-induced 15 kDa protein; Interferon-induced 17 kDa protein; IP17; Ubiquitin cross-reactive protein 

Gene Name

 Isg15 

Gene Synonyms/Alias

 G1p2; Ucrp 

Created Date

 July 27, 2013 

Organism

 Mus musculus (Mouse) 

NCBI Taxa ID

 10090 

Lysine Modification

Position	Peptide	Type	References
6	**MAWDLKVKMLGGN	acetylation	[1]
6	**MAWDLKVKMLGGN	ubiquitination	[2]
35	LKKQIAQKIGVPAFQ	ubiquitination	[2]
106	TQTVDTLKKKVSQRE	ubiquitination	[2]
141	LLGEYGLKPQCTVIK	acetylation	[1]
141	LLGEYGLKPQCTVIK	ubiquitination	[2]
148	KPQCTVIKHLRLRGG	ubiquitination	[2]

Reference

 [1] Quantitative acetylome analysis reveals the roles of SIRT1 in regulating diverse substrates and cellular pathways.
 Chen Y, Zhao W, Yang JS, Cheng Z, Luo H, Lu Z, Tan M, Gu W, Zhao Y.
 Mol Cell Proteomics. 2012 Oct;11(10):1048-62. [PMID: 22826441]
 [2] Proteomic analyses reveal divergent ubiquitylation site patterns in murine tissues.
 Wagner SA, Beli P, Weinert BT, Schölz C, Kelstrup CD, Young C, Nielsen ML, Olsen JV, Brakebusch C, Choudhary C.
 Mol Cell Proteomics. 2012 Dec;11(12):1578-85. [PMID: 22790023] 

Functional Description

 Ubiquitin-like protein that is conjugated to intracellular target proteins after IFN-alpha or IFN-beta stimulation. Its enzymatic pathway is partially distinct from that of ubiquitin, differing in substrate specificity and interaction with ligating enzymes. ISG15 conjugation pathway uses a dedicated E1 enzyme, but seems to converge with the Ub conjugation pathway at the level of a specific E2 enzyme. Targets include STAT1, SERPINA3G/SPI2A, JAK1, MAPK3/ERK1, PLCG1, EIF2AK2/PKR, MX1/MxA, and RIG-1. Deconjugated by USP18/UBP43. Shows specific chemotactic activity towards neutrophils and activates them to induce release of eosinophil chemotactic factors. May serve as a trans-acting binding factor directing the association of ligated target proteins to intermediate filaments. May also be involved in autocrine, paracrine and endocrine mechanisms, as in cell-to-cell signaling, possibly partly by inducing IFN-gamma secretion by monocytes and macrophages. Seems to display antiviral activity during viral infections (By similarity). 

Sequence Annotation

 DOMAIN 2 76 Ubiquitin-like 1.
 DOMAIN 77 155 Ubiquitin-like 2.
 REGION 151 155 Involved in the ligation of specific
 BINDING 151 151 Activating enzyme (By similarity).
 CROSSLNK 155 155 Glycyl lysine isopeptide (Gly-Lys)  

Keyword

 Antiviral defense; Complete proteome; Cytoplasm; Direct protein sequencing; Isopeptide bond; Reference proteome; Repeat; Secreted; Ubl conjugation pathway. 

Sequence Source

 UniProt (SWISSPROT/TrEMBL); GenBank; EMBL 

Protein Length

 161 AA 

Protein Sequence

Gene Ontology

 GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell.
 GO:0005576; C:extracellular region; ISS:UniProtKB.
 GO:0031386; F:protein tag; IDA:MGI.
 GO:0042742; P:defense response to bacterium; IMP:UniProtKB.
 GO:0051607; P:defense response to virus; IMP:UniProtKB.
 GO:0032020; P:ISG15-protein conjugation; IDA:UniProtKB.
 GO:0019941; P:modification-dependent protein catabolic process; IDA:MGI.
 GO:0031397; P:negative regulation of protein ubiquitination; ISS:UniProtKB.
 GO:0045071; P:negative regulation of viral genome replication; ISS:UniProtKB.
 GO:0045648; P:positive regulation of erythrocyte differentiation; IMP:UniProtKB.
 GO:0032649; P:regulation of interferon-gamma production; ISS:UniProtKB.
 GO:0034340; P:response to type I interferon; ISS:UniProtKB. 

Interpro

 IPR000626; Ubiquitin.
 IPR019955; Ubiquitin_supergroup. 

Pfam

 PF00240; ubiquitin 

SMART

 SM00213; UBQ 

PROSITE

 PS50053; UBIQUITIN_2 

PRINTS