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, 1863 (11), 2613-2623

Orphan Proteins of Unknown Function in the Mitochondrial Intermembrane Space Proteome: New Pathways and Metabolic Cross-Talk


Orphan Proteins of Unknown Function in the Mitochondrial Intermembrane Space Proteome: New Pathways and Metabolic Cross-Talk

Esther Nuebel et al. Biochim Biophys Acta.


The mitochondrial intermembrane space (IMS) is involved in protein transport, lipid homeostasis and metal ion exchange, while further acting in signalling pathways such as apoptosis. Regulation of these processes involves protein modifications, as well as stress-induced import or release of proteins and other signalling molecules. Even though the IMS is the smallest sub-compartment of mitochondria, its redox state seems to be tightly regulated. However, the way in which this compartment participates in the cross-talk between the multiple organelles and the cytosol is far from understood. Here we focus on newly identified IMS proteins that may represent future challenges in mitochondrial research. We present an overview of the import pathways, the recently discovered new components of the IMS proteome and how these relate to key aspects of cell signalling and progress made in stem cell and cancer research.

Keywords: Intermembrane space; Metabolism; Mitochondria; Mitochondrial proteome; Protein import; Redox signalling.


Image 1
Fig. 1
Fig. 1
The IMS proteome of mitochondria is involved in several cellular processes. These include (i) epigenetic regulation in the nucleus, (ii) apoptosis signalling, (iii) regulation of translation, (iv) lipid signalling, (v) signalling via reactive oxygen species (ROS), (vi) maintenance of redox homeostasis and (vii) regulation of metabolism and of the respiratory transport chain (RTC).

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