Advances in research on plant CNGCs, the Ca2+-permeable channels.

Cyclic nucleotide-gated channels (CNGCs) in plants are the orthologs of cyclic nucleotide-gated (CNG) channels, which function as non-selective cation channels in olfactory and visual signal transduction in animals. In land plants, CNGCs form a large Ca2+-permeable cation channel family, and function in diverse biological processes, mainly including the uptake of cationic nutrients and toxic heavy metals from the soil, the transport, distribution, and homeostasis of these cations, and Ca2+ signaling in plants. Significant advances have been made in recent years, with new findings that have greatly expanded our understanding of plant CNGCs. This review summarizes the major progress over the past 5 years and discusses the open scientific questions that remain to be addressed.