کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
2130178 | 1086534 | 2015 | 9 صفحه PDF | دانلود رایگان |
• We present a live-cell assay to probe direct interaction between HIF-2α and HIF-1β.
• Depletion of HIF-1α enhances the heterodimer formation of HIF-2α and HIF-1β.
• HIF-3α variants do not affect the localization of HIF-2α and HIF-1β.
• HIF-3α variants inhibit the heterodimer formation of HIF-2α and HIF-1β.
Hypoxia-inducible factors (HIFs), consisting of α and β subunits, activate various genes to adapt to low oxygen environments through their heterodimeric complex formation in the nucleus. While most of the studies have been extensively focused on the HIF-1α isoform, the effect of HIF-α isoforms on the complex formation between HIF-2α and HIF-1β in live cells has not been reported in detail. To probe these interactions in a physiological condition, we established a fluorescence resonance energy transfer (FRET) assay by introducing fluorescent reporter proteins onto the N-termini of HIF-2α and HIF-1β in live PC3 cells. After thorough validations of our FRET assay system, we showed that both HIF-1α and HIF-3α variants likely function as negative regulators on the heterodimer formation of HIF-2α with HIF-1β in cells. We also characterized the localization and stabilization of HIF-3α variants and measured the interaction between HIF-3α variants and other HIF isoforms in live cells. In contrast to the previous results showing HIF-3α-mediated blockage of HIF-1α translocation, the presence of HIF-3α did not affect the localization of HIF-2α, suggesting distinct roles of HIF-3α in regulation of two HIF-α isoforms.
Journal: Experimental Cell Research - Volume 336, Issue 2, 15 August 2015, Pages 329–337