2. Academic Validation
  3. Plasminogen kringle 5 induces endothelial cell apoptosis by triggering a voltage-dependent anion channel 1 (VDAC1) positive feedback loop

Plasminogen kringle 5 induces endothelial cell apoptosis by triggering a voltage-dependent anion channel 1 (VDAC1) positive feedback loop

  • J Biol Chem. 2014 Nov 21;289(47):32628-38. doi: 10.1074/jbc.M114.567792.
Lei Li 1,  Ya-Chao Yao 2,  Xiao-Qiong Gu 3,  Di Che 4,  Cai-Qi Ma 4,  Zhi-Yu Dai 4,  Cen Li 4,  Ti Zhou 4,  Wei-Bin Cai 4,  Zhong-Han Yang 4,  Xia Yang 5,  Guo-Quan Gao 6
Affiliations

Affiliations

  • 1 From the Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, the Department of Reproductive Medicine Center, Key Laboratory for Reproductive Medicine of Guangdong Province, Third Affiliated Hospital of Guangzhou Medical University, 63 Duobao Road, Guangzhou 510150.
  • 2 the Laboratory Center of Guangdong NO.2 Provincial People's Hospital, Guangzhou 510317.
  • 3 the Department of Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou 510623.
  • 4 From the Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080.
  • 5 From the Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, the China Key Laboratory of Tropical Disease Control, Sun Yat-sen University, Ministry of Education, Guangzhou 510080, and yangxia@mail.sysu.edu.cn.
  • 6 From the Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, the Key Laboratory of Functional Molecules from Marine Microorganisms, Sun Yat-sen University, Department of Education of Guangdong Province, Guangzhou 510080, China gaogq@mail.sysu.edu.cn.
PMID: 25296756 DOI: 10.1074/jbc.M114.567792
Abstract

Human plasminogen kringle 5 (K5) is known to display its potent anti-angiogenesis effect through inducing endothelial cell (EC) Apoptosis, and the voltage-dependent anion channel 1 (VDAC1) has been identified as a receptor of K5. However, the exact role and underlying mechanisms of VDAC1 in K5-induced EC Apoptosis remain elusive. In the current study, we showed that K5 increased the protein level of VDAC1, which initiated the mitochondrial Apoptosis pathway of ECs. Our findings also showed that K5 inhibited the ubiquitin-dependent degradation of VDAC1 by promoting the phosphorylation of VDAC1, possibly at Ser-12 and Thr-107. The phosphorylated VDAC1 was attenuated by the Akt Agonist, glycogen synthase kinase (GSK) 3β inhibitor, and siRNA, suggesting that K5 increased VDAC1 phosphorylation via the AKT-GSK3β pathway. Furthermore, K5 promoted cell surface translocation of VDAC1, and binding between K5 and VDAC1 was observed on the plasma membrane. HKI protein blocked the impact of K5 on the AKT-GSK3β pathway by competitively inhibiting the interaction of K5 and cell surface VDAC1. Moreover, K5-induced EC Apoptosis was suppressed by VDAC1 antibody. These data show for the first time that K5-induced EC Apoptosis is mediated by the positive feedback loop of "VDAC1-AKT-GSK3β-VDAC1," which may provide new perspectives on the mechanisms of K5-induced Apoptosis.

Keywords

Apoptosis; Bax; Cell Biology; Cell Signaling; Cell Surface Receptor; Cellular Regulation; Glycogen Synthase Kinase 3 (GSK-3); Molecular Cell Biology; PI 3-Kinase (PI3K); Phosphorylation.

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