Analyzing Iron and Oxygen-Regulated Protein Complex Formation Using Proteomic Mass Spectrometry

Area of Science:

• Cellular Biology
• Molecular Biology
• Biochemistry

Background:

• Multicellular organisms use complex strategies to adapt to intracellular oxygen changes.
• The von Hippel-Lindau (pVHL) tumor suppressor, prolyl hydroxylases (PHD), and hypoxia-inducible factors (HIFs) form a key oxygen-sensing pathway.
• Oxygen sensing is increasingly understood to be interconnected with cellular iron-sensing pathways.

Purpose of the Study:

• To present a protocol for inducing and maintaining hypoxia in mammalian cell cultures.
• To describe a mass-spectrometry-based proteomics approach for studying protein interactome dynamics.
• To investigate how intracellular oxygen and iron levels remodel protein interactomes.

Main Methods:

• Induction and maintenance of hypoxia in mammalian cell cultures.
• Mass-spectrometry-based proteomics.
• Analysis of protein interactome changes under varying oxygen and iron conditions.

Main Results:

• An oxygen-sensitive interaction between FBXL5 and the CIA targeting complex was previously identified.
• This interaction has implications for FBXL5-dependent regulation of iron regulatory proteins (IRPs).
• The presented methods allow interrogation of protein interactome dynamics in response to oxygen and iron.

Conclusions:

• The developed protocol and proteomics approach are valuable tools for studying iron and oxygen signaling pathways.
• Understanding these dynamics provides insights into cellular homeostasis and adaptation.
• These methods can be broadly applied to various cell types and experimental conditions.