ADAR

Double-stranded RNA-specific adenosine deaminase ;
DRADA ;
136 kDa double-stranded RNA-binding protein ;
p136 ;
Interferon-inducible protein 4 ;
IFI-4 ;
K88DSRBP ;

caution:The N-terminus of isoform 4 has been derived from EST and genomic sequences.,disease:Defects in ADAR are a cause of dyschromatosis symmetrical hereditaria (DSH) [MIM:127400]; also known as reticulate acropigmentation of Dohi. DSH is a pigmentary genodermatosis of autosomal dominant inheritance characterized by a mixture of hyperpigmented and hypopigmented macules distributed on the dorsal parts of the hands and feet.,function:Converts multiple adenosines to inosines and creates I/U mismatched base pairs in double-helical RNA substrates without apparent sequence specificity. Has been found to modify more frequently adenosines in AU-rich regions, probably due to the relative ease of melting A/U base pairs as compared to G/C pairs. Functions to modify viral RNA genomes and may be responsible for hypermutation of certain negative-stranded viruses. Edits the messenger RNAs for glutamate receptor (GLUR) subunits by site-selective adenosine deamination. Produces low-level editing at the GLUR-B Q/R site, but edits efficiently at the R/G site and HOTSPOT1. Binds to short interfering RNAs (siRNA) without editing them and suppresses siRNA-mediated RNA interference. Binds to ILF3/NF90 and up-regulates ILF3-mediated gene expression.,induction:Isoform 1 is induced by interferon alpha. Isoform 5 is constitutively expressed.,PTM:Sumoylation reduces RNA-editing activity.,similarity:Contains 1 A to I editase domain.,similarity:Contains 2 DRADA repeats.,similarity:Contains 3 DRBM (double-stranded RNA-binding) domains.,subcellular location:Isoform 1 is found predominantly in cytoplasm but appears to shuttle between the cytoplasm and nucleus. Isoform 5 is found exclusively in the nucleolus.,subunit:Homodimer. Isoform 1 interacts with ILF2/NF45 and ILF3/NF90.,tissue specificity:Ubiquitously expressed, highest levels were found in brain and lung.,

RNA processing, mRNA processing, RNA modification, negative regulation of macromolecule metabolic process,negative regulation of gene expression, mRNA metabolic process, gene silencing, base conversion or substitution editing, gene silencing by RNA,

[Isoform 1]: Cytoplasm . Nucleus . Shuttles between the cytoplasm and nucleus (PubMed:7565688, PubMed:24753571). Nuclear import is mediated by TNPO1 (PubMed:24753571). .; [Isoform 5]: Cytoplasm . Nucleus . Nucleus, nucleolus . Predominantly nuclear but can shuttle between nucleus and cytoplasm. TNPO1 can mediate its nuclear import whereas XPO5 can mediate its nuclear export. .

Ubiquitously expressed, highest levels were found in brain and lung (PubMed:7972084). Isoform 5 is expressed at higher levels in astrocytomas as compared to normal brain tissue and expression increases strikingly with the severity of the tumor, being higher in the most aggressive tumors.