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AMIGO is an auxiliary subunit of the Kv2.1 potassium channel.

ABSTRACT: Kv2.1 is a potassium channel ?-subunit abundantly expressed throughout the brain. It is a main component of delayed rectifier current (I(K)) in several neuronal types and a regulator of excitability during high-frequency firing. Here we identify AMIGO (amphoterin-induced gene and ORF), a neuronal adhesion protein with leucine-rich repeat and immunoglobin domains, as an integral part of the Kv2.1 channel complex. AMIGO shows extensive spatial and temporal colocalization and association with Kv2.1 in the mouse brain. The colocalization of AMIGO and Kv2.1 is retained even during stimulus-induced changes in Kv2.1 localization. AMIGO increases Kv2.1 conductance in a voltage-dependent manner in HEK cells. Accordingly, inhibition of endogenous AMIGO suppresses neuronal I(K) at negative membrane voltages. In conclusion, our data indicate AMIGO as a function-modulating auxiliary subunit for Kv2.1 and thus provide new insights into regulation of neuronal excitability.

SUBMITTER: Peltola MA

PROVIDER: S-EPMC3245694 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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AMIGO is an auxiliary subunit of the Kv2.1 potassium channel.

Peltola Marjaana A MA Kuja-Panula Juha J Lauri Sari E SE Taira Tomi T Rauvala Heikki H

EMBO reports 20111201 12

Kv2.1 is a potassium channel α-subunit abundantly expressed throughout the brain. It is a main component of delayed rectifier current (I(K)) in several neuronal types and a regulator of excitability during high-frequency firing. Here we identify AMIGO (amphoterin-induced gene and ORF), a neuronal adhesion protein with leucine-rich repeat and immunoglobin domains, as an integral part of the Kv2.1 channel complex. AMIGO shows extensive spatial and temporal colocalization and association with Kv2.1 ...[more]

PMID: 22056818

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