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Distinct cellular distributions of Kv4 pore-forming and auxiliary subunits in rat dorsal root ganglion neurons.

ABSTRACT: Dorsal root ganglia contain heterogeneous populations of primary afferent neurons that transmit various sensory stimuli. This functional diversity may be correlated with differential expression of voltage-gated K(+) (Kv) channels. Here, we examine cellular distributions of Kv4 pore-forming and ancillary subunits that are responsible for fast-inactivating A-type K(+) current.Expression pattern of Kv ?-subunit, ?-subunit and auxiliary subunit was investigated using immunohistochemistry, in situ hybridization and RT-PCR technique.The two pore-forming subunits Kv4.1 and Kv4.3 show distinct cellular distributions: Kv4.3 is predominantly in small-sized C-fiber neurons, whereas Kv4.1 is seen in DRG neurons in various sizes. Furthermore, the two classes of Kv4 channel auxiliary subunits are also distributed in different-sized cells. KChIP3 is the only significantly expressed Ca(2+)-binding cytosolic ancillary subunit in DRGs and present in medium to large-sized neurons. The membrane-spanning auxiliary subunit DPP6 is seen in a large number of DRG neurons in various sizes, whereas DPP10 is restricted in small-sized neurons.Distinct combinations of Kv4 pore-forming and auxiliary subunits may constitute A-type channels in DRG neurons with different physiological roles. Kv4.1 subunit, in combination with KChIP3 and/or DPP6, form A-type K(+) channels in medium to large-sized A-fiber DRG neurons. In contrast, Kv4.3 and DPP10 may contribute to A-type K(+) current in non-peptidergic, C-fiber somatic afferent neurons.

SUBMITTER: Matsuyoshi H

PROVIDER: S-EPMC3667739 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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Distinct cellular distributions of Kv4 pore-forming and auxiliary subunits in rat dorsal root ganglion neurons.

Matsuyoshi Hiroko H Takimoto Koichi K Yunoki Takakazu T Erickson Vickie L VL Tyagi Pradeep P Hirao Yoshihiko Y Wanaka Akio A Yoshimura Naoki N

Life sciences 20120720 7-8

<h4>Aims</h4>Dorsal root ganglia contain heterogeneous populations of primary afferent neurons that transmit various sensory stimuli. This functional diversity may be correlated with differential expression of voltage-gated K(+) (Kv) channels. Here, we examine cellular distributions of Kv4 pore-forming and ancillary subunits that are responsible for fast-inactivating A-type K(+) current.<h4>Main methods</h4>Expression pattern of Kv α-subunit, β-subunit and auxiliary subunit was investigated usin ...[more]

PMID: 22820170

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Dataset Information

Distinct cellular distributions of Kv4 pore-forming and auxiliary subunits in rat dorsal root ganglion neurons.

Publications

Distinct cellular distributions of Kv4 pore-forming and auxiliary subunits in rat dorsal root ganglion neurons.

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