Tumor protein 53-induced nuclear protein-1 (
TP53inp1) is expressed by activation via p53 and p73. The purpose of our study was to investigate the role of
TP53inp1 in response of fibroblasts to ionizing radiation. γ-Ray radiation dose-dependently induces the expression of
TP53inp1
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Tumor protein 53-induced nuclear protein-1 (
TP53inp1) is expressed by activation via p53 and p73. The purpose of our study was to investigate the role of
TP53inp1 in response of fibroblasts to ionizing radiation. γ-Ray radiation dose-dependently induces the expression of
TP53inp1 in human immortalized fibroblast (F11hT) cells. Stable silencing of
TP53inp1 was done via lentiviral transfection of shRNA in F11hT cells. After irradiation the clonogenic survival of
TP53inp1 knockdown (F11hT-shTP) cells was compared to cells transfected with non-targeting (NT) shRNA. Radiation-induced senescence was measured by SA-β-Gal staining and autophagy was detected by Acridine Orange dye and microtubule-associated protein-1 light chain 3 (LC3B) immunostaining. The expression of
TP53inp1,
GDF-15, and
CDKN1A and alterations in radiation induced mitochondrial DNA deletions were evaluated by qPCR.
TP53inp1 was required for radiation (IR) induced maximal elevation of
CDKN1A and
GDF-15 expressions. Mitochondrial DNA deletions were increased and autophagy was deregulated following irradiation in the absence of
TP53inp1. Finally, we showed that silencing of
TP53inp1 enhances the radiation sensitivity of fibroblast cells. These data suggest functional roles for
TP53inp1 in radiation-induced autophagy and survival. Taken together, we suppose that silencing of
TP53inp1 leads radiation induced autophagy impairment and induces accumulation of damaged mitochondria in primary human fibroblasts.
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