mTOR signaling pathway regulates epidermal barrier formation in dogs

SANZ RESSEL BL; BARBEITO CG

Simposio; LASDB2019 Simposio Latinoamericano de Biología de Desarrollo 2019; 2019

Latinoamerican Society Development Biology

The mammalian target of rapamycin (mTOR) signaling pathway has been involvedin key processes such as cell cycle progression, cell growth, and cell fatedecisions in the epidermal kerat inocytes. However, the role of this signalingpathway during the canine epidermal development is still unknown. The presentstudy describes the immunohistochemical expression pattern of pS6Ser235/236,one of the mTOR signaling pathway key effectors, combin ed with the proliferationmarker Ki 67, in skin samples of canine fetuses at different developmental stagesusing a tissue microarray. The expression of pS6Ser235/236 was restricted to thecytoplasm of some cells of the spinous and granular strata during a ll stages of theepidermal differentiation program. This expression pattern for pS6Ser235/236 wasconserved in postnatal skin. In contrast, Ki 67 was restricted to the nucleus of cellsof the basal and spinous strata during all stages of the epidermal deve lopment.These findings show a fundamental role for mTOR in keratinocyte differentiationrather than proliferation during the canine epidermal morphogenesis, similar to thatobserved in adult canine skin.