Single-molecule quantification of lipotoxic expression of activating transcription factor 3

• Published in: Physical chemistry chemical physics : PCCP Vol. 16; no. 39; pp. 21595 - 2161
• Main Authors: Yahiatène, Idir, Aung, Hnin H, Wilson, Dennis W, Rutledge, John C
• Format: Journal Article
• Language: English
• Published: England 21.10.2014
• Subjects: Activating Transcription Factor 3 - biosynthesis; Activating Transcription Factor 3 - metabolism; Activation; Aorta - cytology; Aorta - metabolism; Cells, Cultured; Endothelial Cells - cytology; Endothelial Cells - metabolism; Gene expression; Humans; Lipolysis; Localization; Microscopy; Nanostructure; Networks; Nuclei; Position (location)
• ISSN: 1463-9076; 1463-9084; 1463-9084
• DOI: 10.1039/c4cp03260h

Activating transcription factor 3 (ATF3) is a member of the mammalian activation transcription factor/cAMP, physiologically important in the regulation of pro- and anti-inflammatory target genes. We compared the induction of ATF3 protein as measured by Western blot analysis with single-molecule localization microscopy dSTORM to quantify the dynamics of accumulation of intranuclear ATF3 of triglyceride-rich (TGRL) lipolysis product-treated HAEC (Human Aortic Endothelial Cells). The ATF3 expression rate within the first three hours after treatment with TGRL lipolysis products is about 3500 h −1 . After three hours we detected 33 090 ± 3491 single-molecule localizations of ATF3. This was accompanied by significant structural changes in the F-actin network of the cells at ∼3-fold increased localization precision compared to widefield microscopy after treatment. Additionally, we discovered a cluster size of approximately 384 nanometers of ATF3 molecules. We show for the first time the time course of ATF3 accumulation in the nucleus undergoing lipotoxic injury. Furthermore, we demonstrate ATF3 accumulation associated with increased concentrations of TGRL lipolysis products occurs in large aggregates. Single-molecule detection of nuclear ATF3 in a TGRL lipolysis-product-treated human aortic endothelial cell.