Protein disulfide isomerase externalization in endothelial cells follows classical and unconventional routes

Autor(es)

Araujo, Thais L. S. ; Zeidlera, Julianna D. ; Oliveira, Percillia V. S. ; Dias, Matheus H. ; Armelin, Hugo A. ; Laurindo, Francisco R. M.

• Tipo de documento: Artigo Científico
• Fonte: Free Radical Biology and Medicine; v. 103, p. 199-208, FEB 2017.
• Citações Web of Science: 11

Resumo

Extracellular protein disulfide isomerase (PDIA1) pool mediates thrombosis and vascular remodeling, however its externalization mechanisms remain unclear. We performed systematic pharmacological screening of secretory pathways affecting extracellular PDIA1 in endothelial cells (EC). We identified cell-surface (csPDIA1) and secreted non-particulated PDIA1 pools in EC. Such Golgi bypass also occurred for secreted PDIA1 in EC at baseline or after PMA, thrombin or ATP stimulation. Inhibitors of Type I, II and III unconventional routes, secretory lysosomes and recycling endosomes, including syntaxin-12 deletion, did not impair EC PDIA1 externalization This suggests predominantly Golgi-independent unconventional secretory route(s), which were GRASP55-independent. Also, these data reinforce a vesicular-type traffic for PDIA1. We further showed that PDIA1 traffic is ATP-independent, while actin or tubulin cytoskeletal disruption markedly increased EC PDIA1 secretion. Clathrin inhibition enhanced extracellular soluble PDIA1, suggesting dynamic cycling. Externalized PDIA1 represents <2% of intracellular PDIA1. PDIA1 was robustly secreted by physiological levels of arterial laminar shear in EC and supported alpha 5 integrin thiol oxidation. Such results help clarify signaling and homeostatic mechanisms involved in multiple (patho)physiological extracellular PDIA1 functions. (AU)

• Processo FAPESP: 14/20595-1 - Dissulfeto Isomerase Proteica (PDI) como marcador de risco para trombose e/ou progressão acelerada de aterosclerose em pacientes com hipercolesterolemia familiar e em modelo experimental
• Beneficiário: Percíllia Victória Santos de Oliveira
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 12/02372-0 - Mecanismos e efeitos redox da dissulfeto isomerase proteica epi ou pericelular (epcPDI)
• Beneficiário: Thaís Larissa Araujo de Oliveira Silva
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 09/54764-6 - Regulação da homeostase redox e resposta integrada a estresse pela dissulfeto isomerase protéica (PDI): mecanismos e papel na fisiopatologia e terapêutica de doenças vasculares
• Beneficiário: Francisco Rafael Martins Laurindo
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 13/07937-8 - Redoxoma
• Beneficiário: Ohara Augusto
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs