Abstract
Nonylphenol is an alkyl phenol generated through microbial degradation of non-ionic surfactants in rivers as well as by oxidation and hydrolysis of oxidants in plastic products. Therefore, it is important to assess the endocrine disruption effects of nonylphenol ingested via food and to clarify the molecular mechanism involved. Nonylphenol primarily targets the male reproductive (testes and prostate) system, and may be involved in insufficiency of sperm differentiation and degeneration of the testes and prostate in F1 and F2 mice exposed to nonylphenol at the prenatal stage. In this study, we isolated the human protein NPR1 (Nonylphenol Receptor 1) from a normal human prostate cDNA library as a protein binding to a hormone receptor binding domain of histone acetyltransferase AIB1 in the presence of nonylphenol. Molecular interaction analysis revealed that NPR1 binds nonylphenol with high specificity. Therefore, in addition to the endocrine disruption mechanism occurring through the estrogen receptor, a new mechanism acting via NPR1 was suggested.