Purification of human double-stranded RNA-specific editase 1 (hRED1) involved in editing of brain glutamate receptor B pre-mRNA.
RNAs encoding subunits of glutamate-gated ion channel receptors are posttranscriptionally modified by RNA editing and alternative splicing. The change in amino acid sequence caused by RNA editing can affect both the kinetics and the permeability of the ion channel receptors to cations. Here, we report the purification of a 90-kDa double-stranded RNA-specific adenosine deaminase from HeLa cell nuclear extract that specifically edits the glutamine codon at position 586 in the pre-mRNA of the glutamate receptor B subunit. Site-specific deamination of an adenosine to an inosine converts the glutamine codon to that of arginine. Recently, a gene encoding a double-stranded-specific editase (RED1) was cloned from a rat brain cDNA library. Antibodies generated against the deaminase domain of its human homolog specifically recognized and inhibited the activity of the 90-kDa enzyme, indicating that we have purified hRED1 the human homolog of rat RED1. This enzyme is distinct from double-stranded RNA-specific adenosine deaminase which we and others have previously purified and cloned.
O'Connell
M A
MA
Department of Cell Biology, Biozentrum of the University of Basel, Switzerland.
Gerber
A
A
Keller
W
W
D000243:Adenosine Deaminase / Q000302:isolation & purification*; D000818:Animals; D006367:HeLa Cells / Q000201:enzymology; D006801:Humans; D008970:Molecular Weight; D009694:Nucleic Acid Precursors; D017393:RNA Editing; D012322:RNA Precursors / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000302:isolation & purification*; D051381:Rats; D017470:Receptors, Glutamate / Q000235:genetics*; D013379:Substrate Specificity
D009694:Nucleic Acid Precursors; D012322:RNA Precursors; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D017470:Receptors, Glutamate; C567955:ADARB1 protein, human; D000243:Adenosine Deaminase