Funding
National Natural Science Foundation of China
National Basic Research Program of China
China Postdoctoral Science Foundation
National Key Research and Development Program of China
ARTICLE ABSTRACT
Metabolic activities are often accompanied by cell-cycle progression, yet known connections between these two processes remain limited. Here, we identified the isocitrate dehydrogenase 3β (IDH3β) as a novel substrate of anaphase-promoting complex/cyclosome (APC/C)-CDH1 and an important regulator of the cell cycle. In esophageal squamous cell carcinoma (ESCC), IDH3β was posttranslationally upregulated in late G1 phase, and overexpression of IDH3β accelerated G1–S transition, contributing to the promotion of cell proliferation in vitro and in vivo. α-Ketoglutarate (α-KG), a crucial metabolite in tricarboxylic acid (TCA) cycle, was dependent on IDH3β level and partially accounted for IDH3β-mediated cell growth. IDH3β expression increased PFKFB3 protein levels and enhanced glucose uptake, and high expression of IDH3β correlated with poor survival in patients with ESCC, suggesting a potential application of IDH3β in prognosis. Overall, our results highlight a new molecular connection between cell-cycle regulation and the TCA cycle in ESCC.
These findings show that IDH3β is an APC/C-CDH1 substrate and is expressed in a cell-cycle–dependent manner, highlighting novel molecular cross-talk between the TCA cycle and cell cycle in cancer cells.
