A novel gene downstream of Pax2 is overexpressed in Wilms' tumors and encodes for a Calcineurin A binding protein

Publisher SummaryIn the process of sex determination, the analysis of how SRY (sex determining region on the Y) acts has shed light on how cell fate decisions can be made in the embryo. This factor seems to act as a trigger that initiates the process of cell fate determination leading to Sertoli cell differentiation. But this initial decision is only a tentative one, which needs to be reinforced by a series of events that fix cell fate making a stable system within which the development of the rest of the organ can take place. It provides a clearer idea of how transcription factors can work to regulate differentiation. Specificity is achieved by having the right combination of factors all present within the same cell. To avoid development of gonads with mixed structures the switch triggered by SRY is of an all or nothing type; either there is enough SRY present to ensure testis development or there is not, and ovary development ensues.