Dynamic Expression of the Homeobox Factor PBX1 during Mouse Testis Development

Members of the pre-B-cell leukemia transcription factor (PBX) family homeoproteins are mainly known for their involvement in hematopoietic cell differentiation and development leukemia. The four PBX proteins, PBX1, PBX2, PBX3 PBX4, belong to three amino acid loop extension (TALE) superfamily which important transcriptional cofactors several developmental processes involving homeobox (HOX) factors. Mutations human PBX1 gene responsible cases gonadal dysgenesis with absence male sex while Pbx1 inactivation mouse causes a failure Leydig function. However, no data is available regarding expression profile this testis. To fill knowledge gap, we have characterized during testicular development. Real time PCRs Western blots confirmed presence mRNA protein different Sertoli lines. cellular localization was determined by immunohistochemistry immunofluorescence on testis sections at embryonic postnatal stages. detected interstitial cells peritubular myoid from life until puberty. Most expressing do not express marker CYP17A1, indicating that they differentiated steroidogenically active cells. In adults, somatic populations further supports direct role reproductive