Probable cation/chloride cotransporter that may mediate potassium-chloride cotransport. Involved in plant development and K(+) and Cl(-) homeostasis. May not be involved in sodium-chloride cotransport. Expressed in roots, stems and leaves with higher expression in root and leaf tips. By KCl in roots and leaves. Plants silencing CCC1 have slightly shorter roots and leaves than wild-type, and are more sensitive to KCl treatment during seed germination and plant development. Belongs to the SLC12A transporter family.