# Spatial dynamics of mTOR pathway activity during bovine embryo development

## TL;DR

This study explores how the mTOR pathway activity changes in bovine embryos during early development, focusing on cell differentiation.

## Contribution

The study identifies a specific spatial pattern of mTOR activity in bovine embryos during early development.

## Key findings

- pS6 activity is primarily observed in outer cells of morulae and in the trophectoderm (TE) of early blastocysts.
- mTOR activity decreases in late blastocysts, indicating a specific temporal pattern during development.

## Abstract

The mTOR pathway regulates cell proliferation, growth, survival, and metabolism by integrating nutritional and growth factor signaling. In embryos, its activity is influenced by the availability of nutrients in the culture medium, and it can affect the first cellular differentiation event, driving trophectoderm (TE) formation in mice. We hypothesized that mTOR activity is increased in cells poised to become TE and in differentiated TE cells of early bovine embryos. To test this, we assessed mTOR pathway activity through immunofluorescence detection of phospho-S6 (pS6) using confocal microscopy. In morulae, pS6 activity was primarily observed in the outer cells and in early blastocysts, in the TE, while it disappeared in late blastocysts, suggesting a specific pattern for mTOR localization and activity during early embryonic development in bovine.