Tazarotene-Induced Gene 1 Interacts with DNAJC8 and Regulates Glycolysis in Cervical Cancer Cells

Area of Science:

• Molecular Biology
• Cellular Metabolism
• Cancer Research

Background:

• Tazarotene-induced gene 1 (TIG1) is a retinoid-inducible protein with known tumor suppressor functions.
• The regulation of cellular glycolysis is crucial for cancer cell proliferation and survival.
• Pyruvate kinase M2 (PKM2) plays a key role in the Warburg effect and cancer metabolism.

Purpose of the Study:

• To investigate the role of DNAJ heat shock protein family C member 8 (DNAJC8) as a target of TIG1.
• To elucidate the mechanism by which TIG1 regulates glycolysis and glucose uptake.
• To determine the interplay between TIG1, DNAJC8, and PKM2 in cellular metabolism.

Main Methods:

• Ectopic expression and silencing of DNAJC8 and PKM2 in cell lines.
• Immunofluorescence to detect PKM2 translocation.
• Western blotting to assess protein expression levels (e.g., GLUT1).
• Measurement of glucose uptake assays.
• Co-immunoprecipitation to confirm protein-protein interactions.

Main Results:

• Ectopic DNAJC8 expression promoted PKM2 nuclear translocation and induced glucose transporter 1 (GLUT1) expression, increasing glucose uptake.
• Silencing DNAJC8 or PKM2 reversed the effects of ectopic DNAJC8 on GLUT1 expression and glucose uptake.
• TIG1 directly interacted with DNAJC8 in the cytosol, inhibiting DNAJC8-mediated PKM2 translocation and glucose uptake.
• TIG1 silencing led to increased glucose uptake.

Conclusions:

• TIG1 functions as a critical repressor of DNAJC8 in regulating cellular glucose metabolism.
• The TIG1-DNAJC8 interaction modulates PKM2 nuclear translocation, impacting GLUT1 expression and glucose uptake.
• This regulatory axis offers potential therapeutic targets for metabolic dysregulation in diseases like cancer.