Our previous work [Hibino et al. (1992) Biochem. Biophys. Res. Commun. 184, 853-858] has shown that a highly repetitive component in rat nuclear DNA forms a sequence-directed bend to have the binding affinity for the nuclear scaffold protein, P130. In the present experiment, the mobility shift DNA-binding assay suggested that the formation of the repetitive component-P130 complex is based on some cooperative mode of interaction. The DNase I footprint analysis revealed that the major binding region of this protein in the DNA is located near the center of the 370-bp XmnI repeat which has a strongly bent overall structure. These results imply that a nuclear scaffold protein such as P130 binds to sequence-directed bend(s) in a highly repetitive DNA to play an important role in construction of a higher-order chromatin structure.