RNA Editing

Required Editing

Science's STKE  11 Jul 2000:
Vol. 2000, Issue 40, pp. tw8
DOI: 10.1126/stke.2000.40.tw8

One type of RNA editing involves the conversion of adenosine to inosine by selective deamination. Higuchi et al. created mice with the adenosine deaminase, ADAR2, knocked out and found that the mutant mice die young from excessive seizure activity. The seizures are the result of altered channel properties of AMPA-type glutamate receptors, which are heterodimers between the GluR-A and GluR-B subunits. The altered channel properties are the consequence of decreased levels of the GluR-B subunit because of the lack of RNA editing of this subunit of the AMPA-type glutamate receptor. Unedited transcripts accumulate in the mutant mice, and there is a decrease in the mature RNA for GluR-B. The premature death and seizures were prevented by expression of an edited form of GluR-B in the ADAR2-/- mice. These experiments show that RNA editing can control the rate of transcript splicing and that the GluR-B transcript is a critical substrate for ADAR2.

Higuchi, M., Maas, S., Single, F.N., Hartner, J., Rozov, A., Burnashev, N., Feldmeyer, D., Sprengel, R., and Seeburg, P.H. (2000) Point mutation in an AMPA receptor gene rescues lethality in mice deficient in the RNA-editing enzyme ADAR2. Nature 406: 78-81. [Online Journal]