RNA based antagonist of NMDA receptors.
The N-methyl d-aspartate (NMDA) class of ionotropic glutamate receptors plays important roles in learning and memory as well as in a number of neurological disorders including Huntington's disease and cerebral ischemia. Here, we describe the isolation and characterization of a 2' F-modified RNA aptamers directed against GluN2A-containing NMDA receptors. By adding a negative selection step toward the closely related AMPA and kainate receptors, the RNA aptamers specifically recognize NMDA receptors with dissociation constants in the nanomolar range. Electrophysiological characterization of these aptamers using rapid perfusion in outside-out patches reveals that they selectively inhibit the GluN2A containing subtype of NMDA receptors with little effect on the AMPA and kainate receptor subtypes. We also demonstrate that this RNA aptamer significantly reduces neurotoxicity in an in vitro model of cerebral ischemia. Given that the RNA based antagonist can be readily modified, it can be used as a tool in targeted drug delivery or for imaging purposes in addition to having the potential use as a therapeutic intervention in disorders involving glutamate receptors.
Center for Membrane Biology, Department of Biochemistry and Molecular Biology, and §Department of Neurology, University of Texas Health Science Center , 6431 Fannin, Houston, Texas 77030, United States.
Garam
G
Lee
David M
DM
MacLean
Henning
H
Ulrich
Xiurong
X
Zhao
Jaroslaw
J
Aronowski
Vasanthi
V
Jayaraman
D000818:Animals; D052157:Aptamers, Nucleotide / Q000737:chemistry* / Q000235:genetics / Q000494:pharmacology; D001483:Base Sequence; D015687:Cell Hypoxia / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000187:drug effects / Q000502:physiology; D016384:Consensus Sequence; D005947:Glucose / Q000172:deficiency; D008969:Molecular Sequence Data; D009474:Neurons / Q000187:drug effects / Q000502:physiology; D018696:Neuroprotective Agents / Q000737:chemistry / Q000494:pharmacology; D009690:Nucleic Acid Conformation; D018408:Patch-Clamp Techniques; D011869:Radioligand Assay; D051381:Rats; D018091:Receptors, AMPA / Q000037:antagonists & inhibitors / Q000378:metabolism; D018092:Kainic Acid Receptors / Q000037:antagonists & inhibitors / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors* / Q000378:metabolism
D052157:Aptamers, Nucleotide; D005947:Glucose; D018696:Neuroprotective Agents; D018091:Receptors, AMPA; D018092:Kainic Acid Receptors; D016194:Receptors, N-Methyl-D-Aspartate