The deubiquitinating enzyme USP5 modulates neuropathic and inflammatory pain by enhancing Cav3.2 channel activity

Agustin Garcia-Caballero (1) , Vinicius M. Gadotti (1) , Patrick Stemkowski (1) , Norbert Weiss (1) , Ivana A. Souza (1) , Victoria Hodgkinson (1) , Chris Bladen (1) , Lina Chen (1) , Jawed Hamid (1) , Anne Pizzoccaro (2) , Mickael Deage (2) , Amaury François (2) , Emmanuel Bourinet (2) , Gerald W. Zamponi (1)

1 Department of Physiology and Pharmacology
2 IGF - Institut de Génomique Fonctionnelle

T-type calcium channels are essential contributors to the transmission of nociceptive signals in the primary afferent pain pathway. Here, we show that T-type calcium channels are ubiquitinated by WWP1, a plasma-membrane-associated ubiquitin ligase that binds to the intracellular domain III-IV linker region of the Cav3.2 T-type channel and modifies specific lysine residues in this region. A proteomic screen identified the deubiquitinating enzyme USP5 as a Cav3.2 III-IV linker interacting partner. Knockdown of USP5 via shRNA increases Cav3.2 ubiquitination, decreases Cav3.2 protein levels, and reduces Cav3.2 whole-cell currents. In vivo knockdown of USP5 or uncoupling USP5 from native Cav3.2 channels via intrathecal delivery of Tat peptides mediates analgesia in both inflammatory and neuropathic mouse models of mechanical hypersensitivity. Altogether, our experiments reveal a cell signaling pathway that regulates T-type channel activity and their role in nociceptive signaling.

Mots clés: Mice; Animals; Male; Humans; Transgenic; Membrane Potentials/drug effects/genetics; Peptides/therapeutic use; Sensory Receptor Cells/drug effects/physiology; Spinal Cord/cytology; Ubiquitination/genetics/physiology; Neuralgia/drug therapy/*enzymology; Pain Threshold/drug effects/physiology; Animal; In Vitro Techniques; Cells; Cultured; Calcium Channels; T-Type/genetics/*metabolism; Transfection; Endopeptidases/genetics/*metabolism; Freund's Adjuvant/toxicity; Hyperalgesia/diagnosis/physiopathology; Inflammation/chemically induced/*physiopathology; Nerve Tissue Proteins/metabolism; Disease Models; Inbred C57BL

Domaines: Neurobiologie

Agustin Garcia-Caballero, Vinicius M. Gadotti, Patrick Stemkowski, Norbert Weiss, Ivana A. Souza, et al.. The deubiquitinating enzyme USP5 modulates neuropathic and inflammatory pain by enhancing Cav3.2 channel activity. Neuron, 2014, 83 (5), pp.1144--58. ⟨10.1016/j.neuron.2014.07.036⟩. ⟨hal-01950132⟩