An outward-rectifying plant K+ channel SPORK2 exhibits temperature-sensitive ion-transport activity

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Biol. 2018; 28: 2230-2238.e7https://doi.org/10.1016/j.cub.2018.05.042 Abstract Full Text Full Text PDF PubMed Scopus (21) Google Scholar We also discovered that SPORK2 exhibits temperature-sensitive K+ transport activity in the Xenopus oocyte expression system. Using chimeric channels, we showed that two domains of SPORK2 regulated the temperature sensitivity. Furthermore, heterologously expressed SPORK2 in Arabidopsis guard cells induced temperature-dependent stomatal closure. Therefore, SPORK2 is an ion channel in land plants with temperature-sensitive ion-transport activity that functions similarly to mammalian TRP channels. Our current findings advance the molecular understanding of temperature-sensing mechanisms in plants.