Today I've heard for the first time of calcium-gated ion channels but find it hard to get an idea how they work, where they are located, and which role they play.
I assume calcium-gated ion channels are just a special form of ion-gated ion channels, which would be a fourth group of ion channels next to voltage-, lipid-, and ligand-gated ion channels (with ligands being some larger molecules). But on ion-gated ion channels even less is to be found on the internet.
One specific paper that mentions ion-gated ion channels is this (Experimental Neurology, 2001)
One paper that mentions calcium-gated ion channels is this (New England Journal of Medicine, 2015)
Where do I find a general introduction into ion-gated ion channels - if they exist?