Predicted to enable 3'-5' exonuclease activity; SH3 domain binding activity; and enzyme binding activity. Acts upstream of or within mitotic intra-S DNA damage checkpoint signaling and positive regulation of intrinsic apoptotic signaling pathway in response to DNA damage. Located in cytoplasm and nucleus. Is expressed in retina; testis; and thyroid gland. Orthologous to human RAD9A (RAD9 checkpoint clamp component A). [provided by Alliance of Genome Resources, Apr 2022]