Abstract 13610: Endothelial Cu Transporter Atp7a Promotes Vegfr2 Signaling and Post-ischemic Neovascularization via Regulating Autophagy
| العنوان: | Abstract 13610: Endothelial Cu Transporter Atp7a Promotes Vegfr2 Signaling and Post-ischemic Neovascularization via Regulating Autophagy |
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| المؤلفون: | Mustafa Nazir Okur, Sudhahar Varadarajan, Tohru Fukai, Seock Won Youn, Jack H. Kaplan, Dipankar Ash, Xuexiu Fang, Masuko Ushio-Fukai, Yali Hou, John P O'Brien, Malgorzata McMenamin |
| المصدر: | Circulation. 142 |
| بيانات النشر: | Ovid Technologies (Wolters Kluwer Health), 2020. |
| سنة النشر: | 2020 |
| مصطلحات موضوعية: | biology, business.industry, Angiogenesis, VEGF receptors, Autophagy, ATP7A, Transporter, Ischemic injury, Neovascularization, Physiology (medical), cardiovascular system, Cancer research, biology.protein, Medicine, medicine.symptom, Cardiology and Cardiovascular Medicine, business |
| الوصف: | Background: VEGFR2 (KDR/Flk1) signaling in endothelial cells (ECs) plays a central role in angiogenesis. Copper (Cu) is essential micronutrient and has been implicated in angiogenesis. The P-type ATPase transporter ATP7A is key regulator of Cu homeostasis but its role in VEGFR2 signaling in ECs and post-ischemic neovascularization is entirely unknown. Results: Here we show that ATP7A expression was dramatically increased in the angiogenic ECs in mice hindlimb ischemia model. EC-specific ATP7A deficient mice or Cu transporter-dysfunctional ATP7A mut mice showed significant decrease in blood flow recovery and CD31+ capillary density (angiogenesis) in ischemic tissues compared to their control mice. In cultured human ECs, ATP7A knockdown with siRNA significantly inhibited VEGF-induced migration (67%), capillary network formation on Matrigel (46%). Immunofluorescence, co-immunoprecipitation, and proximity ligation assays showed that VEGF stimulated ATP7A translocation from the trans-Golgi network to the plasma membrane where it bound to VEGFR2. Surprisingly, loss of ATP7A promoted VEGF-induced VEGFR2 protein degradation (56%) and inhibited VEGFR2 signaling via enhancing VEGFR2 ubiquitination (2.0-fold) in a Cu-independent manner. This was associated with reduced cell surface VEGFR2 expression, increased VEGFR2 binding to selective autophagic cargo/adaptor p62/SQSTM1 (60%) and LC3-GFP+autophagic puncta (34%) and autolysosome formation (transmission electron microscopy). Inhibition of autophagy by bafilomycin A1 or chloroquine prevented enhanced VEGFR2 degradation in ATP7A-depleted ECs. Furthermore, overexpression of p62, but not p62 lacking ubiquitin binding domain, or autophagy inducer rapamycin treatment increased VEGFR2 degradation (26% and 87%, respectively) and p62 overexpression inhibited ECs migration (29%). Enhanced autophagy flux due to ATP7A dysfunction in vivo was confirmed by employing autophagy reporter CAG-ATP7A mut -RFP-EGFP-LC3 transgenic mice. Conclusion: Our study uncovers the unexpected and novel function of ATP7A to limit autophagic degradation of VEGFR2, thereby promoting VEGFR2 signaling and angiogenesis, which restores neovascularization in ischemic disease. |
| تدمد: | 1524-4539 0009-7322 |
| DOI: | 10.1161/circ.142.suppl_3.13610 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::dbd8a4c5be24f6b2e6d81335757f6748 https://doi.org/10.1161/circ.142.suppl_3.13610 |
| رقم الانضمام: | edsair.doi...........dbd8a4c5be24f6b2e6d81335757f6748 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15244539 00097322 |
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| DOI: | 10.1161/circ.142.suppl_3.13610 |