A multipronged approach unravels unprecedented protein-protein interactions in the human 2-oxoglutarate dehydrogenase multienzyme complex

Zhou, Jieyu and Yang, Luying and Ozohanics, Olivér and Zhang, Xu and Wang, Junjie and Ambrus, Attila (2018) A multipronged approach unravels unprecedented protein-protein interactions in the human 2-oxoglutarate dehydrogenase multienzyme complex. JOURNAL OF BIOLOGICAL CHEMISTRY, 293 (50). pp. 19213-19227. ISSN 0021-9258


Download (3MB) | Preview


The human 2-oxoglutaric acid dehydrogenase complex (hOGDHc) plays a pivotal role in the tricarboxylic acid (TCA) cycle, and its diminished activity is associated with neurodegenerative diseases. The hOGDHc comprises three components, hE1o, hE2o, and hE3, and we recently reported functionally active E1o and E2o components, enabling studies on their assembly. No atomic-resolution structure for the hE2o component is currently available, so here we first studied the interactions in the binary subcomplexes (hE1o-hE2o, hE1o-hE3, and hE2o-hE3) to gain insight into the strength of their interactions and to identify the interaction loci in them. We carried out multiple physico-chemical studies, including fluorescence, hydrogen-deuterium exchange MS (HDX-MS), and chemical cross-linking MS (CL-MS). Our fluorescence studies suggested a strong interaction for the hE1o-hE2o subcomplex, but a much weaker interaction in the hE1o-hE3 subcomplex, and failed to identify any interaction in the hE2o-hE3 subcomplex. The HDX-MS studies gave evidence for interactions in the hE1o-hE2o and hE1o-hE3 subcomplexes comprising full-length components, identifying: (i) the N-terminal region of hE1o, in particular the two peptides 18YVEEM22 and 27ENPKSVHKSWDIF39 as constituting the binding region responsible for the assembly of the hE1o with both the hE2o and hE3 components into hOGDHc, an hE1 region absent in available X-ray structures; and (ii) a novel hE2o region comprising residues from both a linker region and from the catalytic domain as being a critical region interacting with hE1o. The CL-MS identified the loci in the hE1o and hE2o components interacting with each other.

Item Type: Article
Uncontrolled Keywords: Mass spectrometry (MS); DEHYDROGENASE; Isothermal Titration Calorimetry (ITC); chemical cross-linking MS; human 2-oxoglutarate dehydrogenase complex; hydrogen exchange mass spectrometry; neurodegeneration, oxidative stress; protein complex interaction loci; site-selected fluorescent labeling; tricarboxylic acid cycle (TCA cycle) (Krebs cycle);
Subjects: Q Science / természettudomány > QH Natural history / természetrajz > QH301 Biology / biológia > QH3015 Molecular biology / molekuláris biológia
Depositing User: MTMT SWORD
Date Deposited: 17 Jan 2019 14:55
Last Modified: 17 Jan 2019 14:55

Actions (login required)

Edit Item Edit Item