User:Minman2021/ADAR

Forms of ADAR Enzymes
In mammals, there are three types of ADAR enzymes: ADAR (ADAR1), ADARB1 (ADAR2), and ADARB2 (ADAR3).

ADAR (ADAR1) and ADAR2 (ADARB1)

ADAR one and two are both found within various tissues of the body. These two forms of ADAR are also found to be catalytically active, meaning they can be used as a catalyst in a reaction. Both forms also have similar expression pattern structures of proteins and require substrate double-stranded RNA structures. However, they differ in their editing activity in that both ADAR one and two can edit GluR-B pre-mRNA at the R/G site and only ADAR2 can alter the Q/R site. ADAR1 has been found two have two isoforms, ADAR1p150 and ADARp110. ADAR1p110 is typically found in the nucleus, while ADAR1p150 shuffles between the nucleus and the cytoplasm, mostly present in the cytoplasm.

ADAR3 (ADARB2)

ADAR 3 varies from the other two forms of ADAR in that it is only found within brain tissue. It also is considered to be inactive when it comes to catalytic activity. ADAR3 has been found to be linked to memory and learning in mice, showing that it plays a crucial role in the nervous system. In vitro studies have also shown that ADAR3 might play a role in the regulation of ADAR one and two.