RNA editing of AMPA receptor subunit GluR-B: A base-paired intron-exon structure determines position and efficiency

  title={RNA editing of AMPA receptor subunit GluR-B: A base-paired intron-exon structure determines position and efficiency},
  author={Miyoko Higuchi and Frank N. Single and Martin K{\"o}hler and Bernd Sommer and Rolf Sprengel and P. H. Seeburg},

Regulation of glutamate receptor B pre-mRNA splicing by RNA editing

By comparing the events at the Q/R and R/G sites, it is shown that editing can both stimulate and repress splicing efficiency, and that only properly edited mRNAs become spliced and exported to the cytoplasm.

Structural Requirements for RNA Editing in Glutamate Receptor Pre-mRNAs by Recombinant Double-stranded RNA Adenosine Deaminase (*)

It is shown here that DRADA indeed edits GluR pre-mRNAs, but that it displays selectivity for certain editing sites, and that this substrate selectivity correlated with the base pairing status and sequence environment of the editing-targeted adenosines.

A mammalian RNA editing enzyme

The cloning of complementary DNA for RED1, a dsRNA adenosine deaminase expressed in brain and peripheral tissues that efficiently edits the Q/R site in GluR-B pre-mRNA in vitro is reported, indicating that members of an emerging gene family catalyse adenosines deamination in nuclear transcripts with distinct but overlapping substrate specificities.

Editing of glutamate receptor subunit B pre-mRNA in vitro by site-specific deamination of adenosine

It is shown that the GluR-B pre-mRNA is efficiently and accurately edited in vitro, and that base-pair interactions between the editing site and a sequence in the downstream intron8 are required for substrate recognition.

Editing of Glutamate Receptor Subunit B Pre-mRNA by Splice-site Variants of Interferon-inducible Double-stranded RNA-specific Adenosine Deaminase ADAR1*

Mutational analysis revealed that the functional importance of each of the three RNA-binding motifs of ADAR1 varied with the specific target editing site in GluR-B RNA.

The AMPA receptor subunit GluR-B in its Q/R site-unedited form is not essential for brain development and function.

It is shown that AMPAR-mediated calcium influx into central neurons can be solely regulated by the levels of Q/R site-edited GluR-B relative to other AMPAR subunits, and constitutes proof in vivo that elevated calcium influx through AMPARs need not generate pathophysiological consequences.

Coordination of editing and splicing of glutamate receptor pre-mRNA.

In vivo, allowing cotranscriptional processing, the same construct was found to efficiently edit and splice without interference, suggesting that the two RNA processing events are coordinated.

Point mutation in an AMPA receptor gene rescues lethality in mice deficient in the RNA-editing enzyme ADAR2

It is concluded that this transcript is the physiologically most important substrate of ADAR2, as it specifies an ion channel determinant, the Q/R site, in AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole propionate) receptor GluR-B pre-messenger RNA.



Structural determinants of ion flow through recombinant glutamate receptor channels

The properties of heteromeric wild-type and mutant GluRs revealed that the dominance of GluR-B is due to the arginine residue in the TM2 region, and the steady-state current-voltage relations of glutamate- and kainate-induced currents through homomeric channels fell into two classes.

Molecular cloning and functional expression of glutamate receptor subunit genes.

Three closely related genes, GluR1, GluR2, and GluR3, encode receptor subunits for the excitatory neurotransmitter glutamate. The proteins encoded by the individual genes form homomeric ion channels

Flip and flop: a cell-specific functional switch in glutamate-operated channels of the CNS.

These results identify a switch in the molecular and functional properties of glutamate receptors operated by alternative splicing.

Mammalian ionotropic glutamate receptors

Double-stranded RNA adenosine deaminase as a potential mammalian RNA editing factor.

Double-stranded RNA (dsRNA) adenosine deaminase, or DRADA, is a cellular enzyme that modifies adenosine residues to inosines in dsRNA by hydrolytic deamination, replacing A-U with mismatched I-U base

The mechanism of adenosine to inosine conversion by the double-stranded RNA unwinding/modifying activity: a high-performance liquid chromatography-mass spectrometry analysis.

Although the double-stranded RNA unwinding/modifying activity appears to utilize a catalytic mechanism similar to that of adenosine deaminase, coformycin, a transition-state analogue, will not inhibit the unwinding or modifying activity.

Identification of a site in glutamate receptor subunits that controls calcium permeability

To investigate the structural features that control ion permeation through these ligand-gated channels, mutant receptor subunits with single-amino acid changes were constructed.