NAP Family CG5017 Chaperone Pleiotropically Regulates Human AHR Target Genes Expression in Testis.

To study the regulatory mechanism of the Aryl hydrocarbon receptor (AHR), target genes of transcription are necessary for understanding the normal developmental and pathological processes. Here, we examined the effects of human AHR ligands on male fecundity. To induce ectopic human gene expression, we used transformed with human under the control of a yeast promoter element capable of activation in the two-component system. We found that exogenous AHR ligands decrease the number of gonadal Tj-positive cells. We also found both an increase and decrease of AHR target gene expression, including in genes that control homeostasis and testis development. This suggests that gonadal AHR activation may affect the expression of gene networks that control sperm production and could be critical for fertility not just in but also in humans. Finally, we found that the activation of the expression for some AHR target genes depends on the expression of testis-specific chaperone in gonadal cells. Since belongs to the nucleosome assembly protein (NAP) family and may participate in epigenetic regulation, we propose that this nucleotropic chaperone is essential to provide the human AHR with access to only the defined set of its target genes during spermatogenesis.