Figure 6.

XY Sex Reversal in Embryonic Gonads Lacking Both p38α and p38β MAPKs

(A–F) WMISH of XY double-knockout embryos reveals loss of Sox9 expression (A–C) and gain of Foxl2 expression (D–F) in gonads at 14.5 dpc, when compared with control genotypes.

(G–O) Sry expression is reduced in doubly mutant XY embryonic gonads at 13 ts (N), 16 ts (K), and 17 ts (H), in comparison to XY controls (M, J, and G, respectively). Control embryos lacked at most one copy of p38a. Such control XY gonads never exhibited sex reversal at 14.5 dpc. However, loss of p38α or p38β alleles in the control gonads used here may possibly reduce the observable differences in Sry levels between control and doubly homozygous gonads.