KHC is a family of fungal proteins carrying three transmembrane domains. It is a member of the fungal potassium channel family of transporters, and includes a pair of homologous sequences that localise to distinct zones of the yeast plasma membrane and are induced during the response to mating pheromones. Together KCH1 and KCH2 promote low-affinity K+ uptake and are essential for K+-dependent activation of HACS - a high-affinity Ca2+ influx system that activates calcineurin and is essential for cell survival - in S. cerevisiae cells responding to mating pheromones [1].

1: Activation of an essential calcium signaling pathway in Saccharomyces cerevisiae by Kch1 and Kch2, putative low-affinity potassium transporters. Stefan CP, Zhang N, Sokabe T, Rivetta A, Slayman CL, Montell C, Cunningham KW; Eukaryot Cell. 2013;12:204-214. PMID:23204190