Erythrocyte membrane protein band 4.2 is a protein that in humans is encoded by the EPB42 gene. It is part of the red blood cell cytoskeleton.
Erythrocyte membrane protein band 4.2 is an ATP-binding protein which may regulate the association of band 3 with ankyrin. It probably has a role in erythrocyte shape and mechanical property regulation. Mutations in the EPB42 gene are associated with recessive spherocytic elliptocytosis and recessively transmitted hereditary hemolytic anemia.