Enables chromatin binding activity. Acts upstream of or within humoral immune response mediated by circulating immunoglobulin; isotype switching; and somatic hypermutation of immunoglobulin genes. Predicted to be located in nuclear body and plasma membrane. Predicted to be active in nucleus. Is expressed in several structures, including alimentary system; brain; genitourinary system; limb segment; and nose. Orthologous to human EXO1 (exonuclease 1). [provided by Alliance of Genome Resources, Apr 2022]