Merck

CHK2-FOXK axis promotes transcriptional control of autophagy programs.

Science advances (2020-01-09)
Yuping Chen, Jinhuan Wu, Guang Liang, Guohe Geng, Fei Zhao, Ping Yin, Somaira Nowsheen, Chengming Wu, Yunhui Li, Lei Li, Wootae Kim, Qin Zhou, Jinzhou Huang, Jiaqi Liu, Chao Zhang, Guijie Guo, Min Deng, Xinyi Tu, Xiumei Gao, Zhongmin Liu, Yihan Chen, Zhenkun Lou, Kuntian Luo, Jian Yuan
ABSTRACT

Autophagy is an evolutionarily conserved catabolic process, which plays a vital role in removing misfolded proteins and clearing damaged organelles to maintain internal environment homeostasis. Here, we uncovered the checkpoint kinase 2 (CHK2)-FOXK (FOXK1 and FOXK2) axis playing an important role in DNA damage-mediated autophagy at the transcriptional regulation layer. Mechanistically, following DNA damage, CHK2 phosphorylates FOXK and creates a 14-3-3γ binding site, which, in turn, traps FOXK proteins in the cytoplasm. Because FOXK functions as the transcription suppressor of ATGs, DNA damage-mediated FOXKs' cytoplasmic trapping induces autophagy. In addition, we found that a cancer-derived FOXK mutation induces FOXK hyperphosphorylation and enhances autophagy, resulting in chemoresistance. Cotreatment with cisplatin and chloroquine overcomes the chemoresistance caused by FOXK mutation. Overall, our study highlights a mechanism whereby DNA damage triggers autophagy by increasing autophagy genes via CHK2-FOXK-mediated transcriptional control, and misregulation of this pathway contributes to chemoresistance.

MATERIALS
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Product Description

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