Regulation of Blood–Testis Barrier (BTB) Dynamics during Spermatogenesis via the “Yin” and “Yang” Effects of Mammalian Target of Rapamycin Complex 1 (mTORC1) and mTORC2 - International Review of Cell and Molecular Biology - page 334

Figure 6.4 Stage-specific expression of raptor and rictor versus mTOR in the seminiferous
epithelium of adult rat testes. Relative expression level and localization of mTOR, raptor
and rictor (red) in the seminiferous epithelium from stage V-IX tubules were examined by
immunofluorescence microscopy. Cell nuclei were stained with DAPI (blue) to show the
stages of the tubules. This figure shows that from stage V to IX, mTOR was expressed at rela-
tively similar level at the basal compartment where BTB was located. On the other hand, the
expression of raptor, which is the key binding partner of mTORC1, was transiently induced
at stage IX (indicated by white arrow head) that begin in late stage VIII, most notably at the
BTB, whereas the expression of rictor, which is the key subunit of mTORC2, was found to
decline gradually from stage VII and became barely detectable at late stage VIII through
stage IX (indicated by open arrow head), even though it remained weakly expressed in
these stages. Bar, 50 µm, which applies to all micrograph. For interpretation of the refer-
ences to color in this igure legend, the reader is referred to the online version of this topic.