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Thursday 26 January 2017



Definition: Double-stranded RNA-specific adenosine deaminase is an enzyme that in humans is encoded by the ADAR gene (which stands for adenosine deaminase acting on RNA). See ADAR1 ADAR2

Adenosine deaminases acting on RNA (ADAR) are enzymes responsible for binding to double stranded RNA (dsRNA) and converting adenosine (A) to inosine (I) by deamination.

ADAR protein is a RNA-binding protein, which functions in RNA-editing through post-transcriptional modification of mRNA transcripts by changing the nucleotide content of the RNA.

The conversion from A to I in the RNA disrupt the normal A:U pairing which makes the RNA unstable. Inosine is structurally similar to that of guanine (G) which leads to I to cytosine (C) binding.

In RNA I functions the same as G in both translation and replication. Codon changes can arise from editing which may lead to changes in the coding sequences for proteins and their functions.

Most editing site are found in noncoding regions of RNA such as untranslated regions (UTRs), Alu elements and long interspersed nuclear element (LINEs).

Alternate transcriptional splice variants, encoding different isoforms, have been characterized.


- Germline mutations in this gene have been associated with dyschromatosis symmetrica hereditaria, as well as Aicardi–Goutières syndrome .

- ADAR overexpression is associated with cervical cancer progression and angiogenesis. (28109322)

  • ADAR might play an important role in the occurrence, progression and prognosis of cervical squamous cancer.

- ADAR : Metabolomic and Lipidomic Profiling Identifies The Role of the RNA Editing Pathway in Endometrial Carcinogenesis.

  • ADAR2 is overexpressed in EC and that the increase in expression positively correlates with the aggressiveness of the tumor.
  • Furthermore, silencing of ADAR2 in three EC cell lines resulted in a decreased proliferation rate, increased apoptosis, and reduced migration capabilities in vitro.
  • ADAR2 functions as an oncogene in endometrial carcinogenesis and could be a potential target for improving EC treatment strategies.
  • doi : 10.1038/s41598-017-09169-2

See also


Open references

- ADAR1 overexpression is associated with cervical cancer progression and angiogenesis. Chen Y, Wang H, Lin W, Shuai P. Diagn Pathol. 2017 Jan 21;12(1):12. doi : 10.1186/s13000-017-0600-0 PMID: 28109322 Free