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Q/R site editing in kainate receptor GluR5 and GluR6 pre-mRNAs requires distant intronic sequences.

ABSTRACT: RNA editing by adenosine deamination in brain-expressed pre-mRNAs for glutamate receptor (GluR) subunits alters gene-specified codons for functionally critical positions, such as the channel's Q/R site. We show by transcript analysis of minigenes transiently expressed in PC-12 cells that, in contrast to GluR-B pre-mRNA, where the two editing sites (Q/R and R/G) require base pairing with nearby intronic editing site complementary sequences (ECSs), editing in GluR5 and GluR6 pre-mRNAs recruits an ECS located as far as 1900 nucleotides distal to the Q/R site. The exon-intron duplex structure of the GluR5 and GluR6 pre-mRNAs appears to be a substrate of double-stranded RNA-specific adenosine deaminase. This enzyme when coexpressed in HEK 293 cells preferentially targets the adenosine of the Q/R site and of an unpaired position in the ECS which is highly edited in brain.

SUBMITTER: Herb A

PROVIDER: S-EPMC39875 | biostudies-other | 1996 Mar

REPOSITORIES: biostudies-other

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Q/R site editing in kainate receptor GluR5 and GluR6 pre-mRNAs requires distant intronic sequences.

Herb A A Higuchi M M Sprengel R R Seeburg P H PH

Proceedings of the National Academy of Sciences of the United States of America 19960301 5

RNA editing by adenosine deamination in brain-expressed pre-mRNAs for glutamate receptor (GluR) subunits alters gene-specified codons for functionally critical positions, such as the channel's Q/R site. We show by transcript analysis of minigenes transiently expressed in PC-12 cells that, in contrast to GluR-B pre-mRNA, where the two editing sites (Q/R and R/G) require base pairing with nearby intronic editing site complementary sequences (ECSs), editing in GluR5 and GluR6 pre-mRNAs recruits an ...[more]

PMID: 8700852

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