Here too, studies in 35-day-old and adult SCARKO testes indicate that, despite the formation of tight junctions, lanthanum may be seen in the adluminal compartment of some tubules.
The involvement of the brain in gonad development has been established by studies on quail which showed that males transplanted with female forebrains had abnormally developed testes, indicating that a genetically male brain is necessary for normal testis development [16].
Expression patterns of TCF21 in the E13 and E14 testes indicate a transient role in Sertoli cell differentiation, whereas expression at E16 in the interstitium suggests a role during later Leydig cell differentiation [14], [16].
Expression profiles for mature parr and maturing adult testes indicate subtle differences in gene expression between these two related groups.
There was comparable vimentin staining between Bscl2+/+ and Bscl2−/− testes, indicating no obvious structural abnormality of the Sertoli cells that support sperm cell development before the spermatids are released to the lumen.
Intriguingly, such defects of E-cadherin distribution in the germ cells were similarly found in seAip1−/− testes, indicating that AIP1 loss-of-function in Sertoli cells had a non-autonomous effect on germ cells.
From P2 to P4, there were no significant differences in the Nbasal or Ncentral values between the mutant (geAip1−/− or seAip1−/−) and control testes, indicating that germ cells in both mutants migrate normally from P2 to P4.
Surprisingly, significant upregulation of E-cadherin was also detected in Sertoli cells in the P7 geAip1−/− testes, indicating that Aip1-deleted germs cells had a non-autonomous effect on the wild-type Sertoli cells.
The percentage of seminiferous tubules that are positive for L1 ORF1 protein (ORF1p) in Cbx3 hypo / hypo testes is greater than that for wild-type testes, indicating that L1 retrotransposon silencing is reversed, leading to ectopic expression of ORF1p in Cbx3 hypo / hypo germ cells.
