Enables ketohexokinase activity. Acts upstream of or within fructose metabolic process and regulation of glycogen metabolic process. Located in cytoplasm and nucleus. Is expressed in alimentary system; central nervous system; liver; and retina. Human ortholog(s) of this gene implicated in essential fructosuria. Orthologous to human KHK (ketohexokinase). [provided by Alliance of Genome Resources, Apr 2022]