BACKGROUND: Murine cytomegalovirus (MCMV) early protein M112-113 is involved in viral DNA replication and believed to play a crucial role in the viral pathogenesis. To investigate the biological function of M112-113 protein in the pathogenesis of the brain disorders caused by cytomegalovirus (CMV), a screening for proteins interacting with M112-113 was performed by a yeast two-hybrid system. METHODS: Bait plasmid pGBKT7-M112-113 was constructed and transformed into AH109 yeast. After confirmation of the expression of MCMV M112-113 in yeast, the bait yeast was mated with a prey yeast containing mouse brain cDNA library plasmid to screen the proteins interacting with M112-113. Interactions between M112-113 and the obtained proteins were verified by yeast two-hybrid assay and chemiluminescent co-immunoprecipitaion. RESULTS: Two proteins interacting with M112-113 were identified, including metastasis-associated 1 (MTA1) and zinc finger, CCHC domain containing 18 (ZCCHC18). M112-113 protein could interact with MTA1 or ZCCHC18 in yeast and mammalian cells. CONCLUSION: The interactions of M112-113 with MTA1 or ZCCHC18 may be related to the pathogenesis of MCMV-associated disease in central nervous system.