Dataset Information

Merkel cells transduce and encode tactile stimuli to drive A?-afferent impulses.

ABSTRACT: Sensory systems for detecting tactile stimuli have evolved from touch-sensing nerves in invertebrates to complicated tactile end organs in mammals. Merkel discs are tactile end organs consisting of Merkel cells and A?-afferent nerve endings and are localized in fingertips, whisker hair follicles, and other touch-sensitive spots. Merkel discs transduce touch into slowly adapting impulses to enable tactile discrimination, but their transduction and encoding mechanisms remain unknown. Using rat whisker hair follicles, we show that Merkel cells rather than A?-afferent nerve endings are primary sites of tactile transduction and identify the Piezo2 ion channel as the Merkel cell mechanical transducer. Piezo2 transduces tactile stimuli into Ca(2+)-action potentials in Merkel cells, which drive A?-afferent nerve endings to fire slowly adapting impulses. We further demonstrate that Piezo2 and Ca(2+)-action potentials in Merkel cells are required for behavioral tactile responses. Our findings provide insights into how tactile end-organs function and have clinical implications for tactile dysfunctions.

SUBMITTER: Ikeda R

PROVIDER: S-EPMC4003503 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature

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Merkel cells transduce and encode tactile stimuli to drive Aβ-afferent impulses.

Ikeda Ryo R Cha Myeounghoon M Ling Jennifer J Jia Zhanfeng Z Coyle Dennis D Gu Jianguo G JG

Cell 20140415 3

Sensory systems for detecting tactile stimuli have evolved from touch-sensing nerves in invertebrates to complicated tactile end organs in mammals. Merkel discs are tactile end organs consisting of Merkel cells and Aβ-afferent nerve endings and are localized in fingertips, whisker hair follicles, and other touch-sensitive spots. Merkel discs transduce touch into slowly adapting impulses to enable tactile discrimination, but their transduction and encoding mechanisms remain unknown. Using rat whi ...[more]

PMID: 24746027

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Dataset Information

Merkel cells transduce and encode tactile stimuli to drive A?-afferent impulses.

Publications

Merkel cells transduce and encode tactile stimuli to drive Aβ-afferent impulses.

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