E-Locus - Institutional Repository of the University of Crete

Home Search

Results - Details

Search command : Author="Τοκατλίδης" And Author="Κωνσταντίνος"

Current Record: 6 of 9

[Add to Basket]

Identifier

000381653

Title

Μηχανικμός λειτουργίας και μοριακών αλληλεπιδράσεων της σουλφυδριλοξείδασης Εrv1 στο μιτοχόνδριο του σακχαρομύκητα

Alternative Title

Function and molecular interactions of Erv1 sulfphydryl oxidase in yeast mitochondria

Author

Καλλέργη, Εμμανουέλα Γ

Thesis advisor

Τοκατλίδης, Κωνσταντίνος

Reviewer

Σπηλιανάκης, Χ.
Ταβερναράκης, Ν.

Abstract

Mitochondria are essential organelles of eukaryotic cells as they play a central role in many cellular procedures as respiration, ATP production and apoptosis. Biogenesis of mitochondria depends on mitochondrial protein import performed by different import pathways. Recently, MIA pathway has been described as a disulfide oxidative system in Saccharomyces cerevisiae that gives disulfides in a variety of different proteins in the mitochondrial intermembrane space (IMS). Functionallity of this pathway depends on two proteins: the sulfhydryl oxidase Erv1/ALR and the oxidoreductase Mia40, that together drive the import of preproteins with conserved cysteines, into the IMS through their oxidative folding. In this PhD thesis, we study the Mia40-Erv1 bimodal interaction by mainly biochemical, in organello, in vitro and in vivo approaches, that occurs in two different steps: (a) Erv1, gets recognized and oxidized by Mia40, as a substrate of MIA pathway (Step A) and (b) folded and functional Erv1 oxidizes the active site of Mia40 (Step B). Studying the import and maturation of Erv1 (Step A) we characterized the minimal region in its carboxyl-terminal part that is required for its recognition and oxidation by Mia40 before the subsequent binding of FAD molecule per its monomer. On the other hand, studying the role of Erv1 in Mia40 re-oxidation (Step B) we found that certain hydrophobic residues downstream of the cysteine motif CRSC N-terminally of Erv1 are required for Mia40 recycling, but not for its mitochondrial import. Moreover, our results showed the part of the first 72 largely unstructured amino acids of Erv1 (N72) shows a targeting role in cytosol, apart from its role in Mia40 re-oxidation. This compartment-dependent redox control of the amino-terminal part of Erv1 raises additional questions concerning its interaction with the outer mitochondrial membrane as well as cytosolic chaperones. The above results give us more information in the field of mitochondrial import in order to study in more detail the Mia40-Erv1 molecular interaction which is crucial for the Erv1 biogenesis, the function of the MIA pathway and hence for the mitochondrial biogenesis and cell viability.

Language

Greek

Subject

Cysteines

Disuflide bond

Erv1/ALR

Intermembrane space

Nuclear magnetic resonance

Oxidative folding

Saccharomyces cerevisiae

Διαμεμβρανικός χώρος

Δισουλφιδικός δεσμός