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Abstract #48841 Published in IGR 14-1
Transduction of PTEN proteins using the tat domain modulates TGF-β1-mediated signaling pathways and transdifferentiation in subconjunctival fibroblasts
Chung EJ; Lee HK; Jung SA; Lee SJ; Chee HY; Sohn YH; Lee JHInvestigative Ophthalmology and Visual Science 2012; 53: 379-386
PURPOSE: This study investigated the effects of the tumor suppressor protein PTEN (phosphatase and tensin homolog) on transforming growth factor (TGF)-β1-mediated signaling pathways and the transdifferentiation of human subconjunctival fibroblasts (SCFs) after the transduction of this protein containing a transactivator of transcription (Tat) domain. METHODS: The Tat-PTEN expression vector was constructed to express the Tat domain of HIV-1 fused to PTEN. After transduction of the fusion protein and TGF-β1 stimulation, the dose-dependent effect of the transduced Tat-PTEN fusion protein on Akt phosphorylation and the stability of the Tat-PTEN fusion protein in SCF cells were evaluated by Western blot analysis. The effect of the Tat-PTEN fusion protein on the TGF-β1-stimulated expression of α-SMA and fibronectin was also evaluated by Western blot analysis and immunocytochemistry. RESULTS: To increase the efficiency of enzyme activity and to successfully deliver this protein to cells, the authors used a PTEN fusion protein that contained the transduction domain of the Tat protein from HIV-1. By Western blot analysis, the transduced Tat-PTEN fusion protein was found to modulate TGF-β1 signaling in SCF cells and result in the suppression of Akt phosphorylation. Furthermore, the transduction of the Tat-PTEN fusion protein was found to suppress the TGF-β1-stimulated expression of α-SMA and fibronectin by Western blot analysis and immunocytochemical staining, and the effects of the transduced fusion protein could be controlled in a dose-dependent manner. CONCLUSIONS: The Tat-PTEN fusion proteins were successfully transduced into the SCF cells and induced the suppression of transdifferentiation and fibrosis through the regulation of TGF-β-mediated signaling. The ability of the Tat-PTEN fusion protein to regulate cell survival could potentially be applied to protein therapy to counteract postoperative scarring in glaucoma surgery.
Department of Ophthalmology, National Health Insurance Corporation Ilsan Hospital, Gyounggi-do, Korea.
Full articleClassification:
3.5 Molecular biology incl. SiRNA (Part of: 3 Laboratory methods)
3.6 Cellular biology (Part of: 3 Laboratory methods)
12.8.10 Woundhealing antifibrosis (Part of: 12 Surgical treatment > 12.8 Filtering surgery)
