Enables retinoid X receptor binding activity. Predicted to be involved in several processes, including histone H2A K63-linked deubiquitination; mitotic G2 DNA damage checkpoint signaling; and regulation of nucleobase-containing compound metabolic process. Predicted to act upstream of or within cellular response to DNA damage stimulus and chromatin organization. Predicted to be located in nuclear body. Predicted to be part of BRCA1-A complex. Orthologous to human UIMC1 (ubiquitin interaction motif containing 1). [provided by Alliance of Genome Resources, Apr 2022]