BioProject

TGFβ is known to be a potent inducer of EMT, a process involved in tumor invasion. More...

TGFβ is known to be a potent inducer of EMT, a process involved in tumor invasion. TIF1γ has been reported to participate to TGFβ signaling. In order to understand the role of TIF1γ in TGFβ signaling and its requirement for EMT, we analyzed the TGFβ1 response of human mammary epithelial cell lines. A strong EMT increase was observed in TIF1γ-silenced cells after TGFβ1 treatment, whereas Smad4 inactivation completely blocked this process. In support of these observations, microarray data show that the functions of several TIF1γ target genes can be linked to EMT. As a negative regulator of Smad4, TIF1γ could be critical for the regulation of TGFβ signaling. This work highlights the molecular relationship between TIF1γ and Smad4 in TGFβ1 signaling and EMT. Overall design: Total mRNA extractions were performed for 11 samples from transfected HMEC-TR. Replicates are rimo1, 6; rimo3, 9; rimo2, 7; rimo 4, 10 and rimo 5, 11. Rimo 8 is a single experiment. All RNA extractions were obtained from two independent cell cultures excepted for rimo8. Rimo 1, 6 are replicate for ctrl-; Rimo 3, 9 are replicate for ctrl+; Rimo 2, 7 are replicate for SiTIF-; Rimo 4, 10 are replicate for SiTIF+; Rimo8 is SiSmad4-; and Rimo5, 11 are replicate for SiSmad4+. ctrl means that HMEC-TR were transfected with an SiRNA scramble. "siSmad4" means that HMEC-TR were transfected with an SiRNA anti Smad4. "siTIF" means that HMEC-TR were transfected with an SiRNA anti TIF1γ. "-" means that cells were grown without TGFβ. "+" means that cells were treated with 5 ng/ml TGFβ1 for 24h. Less...