title: Bidirectional integrative regulation of Cav1.2 calcium channel by microRNA miR-103: role in pain.
abstract: Chronic pain states are characterized by long-term sensitization of spinal cord neurons that relay nociceptive information to the brain. Among the mechanisms involved, up-regulation of Cav1.2-comprising L-type calcium channel (Cav1.2-LTC) in spinal dorsal horn have a crucial role in chronic neuropathic pain. Here, we address a mechanism of translational regulation of this calcium channel. Translational regulation by microRNAs is a key factor in the expression and function of eukaryotic genomes. Because perfect matching to target sequence is not required for inhibition, theoretically, microRNAs could regulate simultaneously multiple mRNAs. We show here that a single microRNA, miR-103, simultaneously regulates the expression of the three subunits forming Cav1.2-LTC in a novel integrative regulation. This regulation is bidirectional since knocking-down or over-expressing miR-103, respectively, up- or down-regulate the level of Cav1.2-LTC translation. Functionally, we show that miR-103 knockdown in naive rats results in hypersensitivity to pain. Moreover, we demonstrate that miR-103 is down-regulated in neuropathic animals and that miR-103 intrathecal applications successfully relieve pain, identifying miR-103 as a novel possible therapeutic target in neuropathic chronic pain.
authors.affiliation: CNRS, IINS, UMR 'Central Mechanisms of Pain Sensitization', Bordeaux, France. alexandre.favereaux@u-bordeaux2.fr
authors.forename: Alexandre
authors.initials: A
authors.lastname: Favereaux
authors.forename: Olivier
authors.initials: O
authors.lastname: Thoumine
authors.forename: Rabia
authors.initials: R
authors.lastname: Bouali-Benazzouz
authors.forename: Virginie
authors.initials: V
authors.lastname: Roques
authors.forename: Marie-Amélie
authors.initials: MA
authors.lastname: Papon
authors.forename: Sherine Abdel
authors.initials: SA
authors.lastname: Salam
authors.forename: Guillaume
authors.initials: G
authors.lastname: Drutel
authors.forename: Claire
authors.initials: C
authors.lastname: Léger
authors.forename: André
authors.initials: A
authors.lastname: Calas
authors.forename: Frédéric
authors.initials: F
authors.lastname: Nagy
authors.forename: Marc
authors.initials: M
authors.lastname: Landry
mesh_terms: D000818:Animals; D020746:Calcium Channels, L-Type / Q000096:biosynthesis*; D005786:Gene Expression Regulation; D035683:MicroRNAs / Q000378:metabolism*; D010146:Pain; D014176:Protein Biosynthesis; D051381:Rats
chemical_list: D020746:Calcium Channels, L-Type; D035683:MicroRNAs