Corrigendum: Calmodulin is responsible for Ca2+-dependent regulation of TRPA1 Channels.
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ABSTRACT:
SUBMITTER: Hasan R
PROVIDER: S-EPMC5417011 | biostudies-literature | 2017 May
REPOSITORIES: biostudies-literature
Publications
Corrigendum: Calmodulin is responsible for Ca<sup>2+</sup>-dependent regulation of TRPA1 Channels.
Hasan Raquibul R Leeson-Payne Alasdair T S ATS Jaggar Jonathan H JH Zhang Xuming X
Scientific reports 20170504
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Project description:TRPA1 is a Ca2+-permeable ion channel involved in many sensory disorders such as pain, itch and neuropathy. Notably, the function of TRPA1 depends on Ca2+, with low Ca2+ potentiating and high Ca2+ inactivating TRPA1. However, it remains unknown how Ca2+ exerts such contrasting effects. Here, we show that Ca2+ regulates TRPA1 through calmodulin, which binds to TRPA1 in a Ca2+-dependent manner. Calmodulin binding enhanced TRPA1 sensitivity and Ca2+-evoked potentiation of TRPA1 at low Ca2+, but inhibited TRPA1 sensitivity and promoted TRPA1 desensitization at high Ca2+. Ca2+-dependent potentiation and inactivation of TRPA1 were selectively prevented by disrupting the interaction of the carboxy-lobe of calmodulin with a calmodulin-binding domain in the C-terminus of TRPA1. Calmodulin is thus a critical Ca2+ sensor enabling TRPA1 to respond to diverse Ca2+ signals distinctly.
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