The effects of interaction between histones and human autocrine motility factor receptor (hAMFR) gene promoter on the transcription activity in vitro was investigated by using histones purified from chicken erythrocytes, HeLa cell nuclear extracts and heat-treated supernatants of Xenopus eggs. The results showed that the competitive binding of histones and transcription factors at the promoter of hAMFR gene was very important to the transcription in vitro. If a pre-initiation complex was formed with HeLa cell nuclear extracts on the promoter prior to nucleosome assembly, it would prevent nucleosome-mediated transcription repression. When the nucleosome was assembled on the promoter in advance, the transcription activity could be repressed. When histones and HeLa cell nuclear extracts were mixed in the reaction simultaneously, the transcription activity would depend on the relative amount of histones to that of HeLa cell nuclear extracts.