Predicted to enable heme binding activity; transmembrane ascorbate ferrireductase activity; and transmembrane monodehydroascorbate reductase activity. Predicted to be involved in ascorbate homeostasis. Predicted to be located in vesicle. Predicted to be active in endoplasmic reticulum. Orthologous to human CYB561D2 (cytochrome b561 family member D2). [provided by Alliance of Genome Resources, Apr 2022]