Succination of Dihydrolipoyllysine Succinyltransferase (DLST) Exacerbates Mitochondrial ATP Deficiency in a Mouse Model of Leigh Syndrome

SummaryThe NDUFS4 knockout (KO) mouse phenotype resembles the human Complex I deficiency Leigh Syndrome. The irreversible succination of protein thiols by fumarate is increased in regions of the NDUFS4 KO brain affected by neurodegeneration, suggesting a mechanistic role in neurodegenerative decline. We report the identification of a novel succinated protein, dihydrolipoyllysine-residue succinyltransferase (DLST), a component of the α-ketoglutarate dehydrogenase complex (KGDHC) of the tricarboxylic acid (TCA) cycle. Succination of DLST reduced KGDHC activity in the brainstem (BS) and olfactory bulb (OB) of KO mice. We further observed decreased mitochondrial substrate level phosphorylation, a TCA cycle reaction dependent on KGDHC derived succinyl-CoA, further aggravating the OXPHOS ATP deficit. Protein succinylation, an acylation modification that requires succinyl-CoA, was reduced in the KO mice. Our data demonstrate that the biochemical deficit extends beyond the Complex I assembly and energy defect, and functionally impairs multiple mitochondrial parameters to accelerate neuronal dysfunction.

Download Full-text

CIA30 complex I assembly factor: a candidate for human complex I deficiency?

Human Genetics ◽

10.1007/s00439-001-0673-3 ◽

2002 ◽

Vol 110 (3) ◽

pp. 264-270 ◽

Cited By ~ 48

Author(s):

Rolf Janssen ◽

Jan Smeitink ◽

Roel Smeets ◽

Lambert van den Heuvel

Keyword(s):

Complex I ◽

Complex I Deficiency ◽

Assembly Factor ◽

Complex I Assembly ◽

Human Complex

Download Full-text

TAT-Conjugated NDUFS8 Can Be Transduced into Mitochondria in a Membrane-Potential-Independent Manner and Rescue Complex I Deficiency

International Journal of Molecular Sciences ◽

10.3390/ijms22126524 ◽

2021 ◽

Vol 22 (12) ◽

pp. 6524

Author(s):

Bo-Yu Lin ◽

Gui-Teng Zheng ◽

Kai-Wen Teng ◽

Juan-Yu Chang ◽

Chao-Chang Lee ◽

...

Keyword(s):

Membrane Potential ◽

Fusion Proteins ◽

Complex I ◽

Nadh Dehydrogenase ◽

Leigh Syndrome ◽

Protein Transduction ◽

Independent Manner ◽

Complex I Deficiency ◽

Transactivator Of Transcription ◽

Hiv 1

NADH dehydrogenase (ubiquinone) Fe-S protein 8 (NDUFS8) is a nuclear-encoded core subunit of human mitochondrial complex I. Defects in NDUFS8 are associated with Leigh syndrome and encephalomyopathy. Cell-penetrating peptide derived from the HIV-1 transactivator of transcription protein (TAT) has been successfully applied as a carrier to bring fusion proteins into cells without compromising the biological function of the cargoes. In this study, we developed a TAT-mediated protein transduction system to rescue complex I deficiency caused by NDUFS8 defects. Two fusion proteins (TAT-NDUFS8 and NDUFS8-TAT) were exogenously expressed and purified from Escherichia coli for transduction of human cells. In addition, similar constructs were generated and used in transfection studies for comparison. The results showed that both exogenous TAT-NDUFS8 and NDUFS8-TAT were delivered into mitochondria and correctly processed. Interestingly, the mitochondrial import of TAT-containing NDUFS8 was independent of mitochondrial membrane potential. Treatment with TAT-NDUFS8 not only significantly improved the assembly of complex I in an NDUFS8-deficient cell line, but also partially rescued complex I functions both in the in-gel activity assay and the oxygen consumption assay. Our current findings suggest the considerable potential of applying the TAT-mediated protein transduction system for treatment of complex I deficiency.

Download Full-text

P311 Defective Complex I assembly due to C20orf7 mutations as a new cause of Leigh syndrome

European Journal of Paediatric Neurology ◽

10.1016/s1090-3798(09)70369-1 ◽

2009 ◽

Vol 13 ◽

pp. S118

Author(s):

I.F.M. de Coo ◽

M. Gerards ◽

W. Sluiter ◽

B.J.C. van den Bosch ◽

M. Frentzen ◽

...

Keyword(s):

Complex I ◽

Leigh Syndrome ◽

Complex I Assembly

Download Full-text

Impaired complex I assembly in a Leigh syndrome patient with a novel missense mutation in the ND6 gene

Annals of Neurology ◽

10.1002/ana.10734 ◽

2003 ◽

Vol 54 (5) ◽

pp. 665-669 ◽

Cited By ~ 75

Author(s):

Cristina Ugalde ◽

Ralf H. Triepels ◽

Marieke J.H. Coenen ◽

Lambert P. Van Den Heuvel ◽

Roel Smeets ◽

...

Keyword(s):

Missense Mutation ◽

Complex I ◽

Leigh Syndrome ◽

Syndrome Patient ◽

Complex I Assembly

Download Full-text

Mutations in Complex I Assembly Factor TMEM126B Result in Muscle Weakness and Isolated Complex I Deficiency

The American Journal of Human Genetics ◽

10.1016/j.ajhg.2016.05.022 ◽

2016 ◽

Vol 99 (1) ◽

pp. 208-216 ◽

Cited By ~ 25

Author(s):

Laura Sánchez-Caballero ◽

Benedetta Ruzzenente ◽

Lucas Bianchi ◽

Zahra Assouline ◽

Giulia Barcia ◽

...

Keyword(s):

Muscle Weakness ◽

Complex I ◽

Complex I Deficiency ◽

Assembly Factor ◽

Complex I Assembly

Download Full-text

Acadian variant of Fanconi syndrome is caused by mitochondrial respiratory chain complex I deficiency due to a non-coding mutation in complex I assembly factor NDUFAF6

Human Molecular Genetics ◽

10.1093/hmg/ddw245 ◽

2016 ◽

Vol 25 (18) ◽

pp. 4062-4079 ◽

Cited By ~ 26

Author(s):

Hana Hartmannová ◽

Lenka Piherová ◽

Kateřina Tauchmannová ◽

Kendrah Kidd ◽

Philip D. Acott ◽

...

Keyword(s):

Respiratory Chain ◽

Complex I ◽

Fanconi Syndrome ◽

Chain Complex ◽

Mitochondrial Respiratory Chain ◽

Respiratory Chain Complex ◽

Mitochondrial Respiratory Chain Complex ◽

Complex I Deficiency ◽

Assembly Factor ◽

Complex I Assembly

Download Full-text

Mitochondrial network complexity and pathological decrease in complex I activity are tightly correlated in isolated human complex I deficiency

AJP Cell Physiology ◽

10.1152/ajpcell.00104.2005 ◽

2005 ◽

Vol 289 (4) ◽

pp. C881-C890 ◽

Cited By ~ 121

Author(s):

Werner J. H. Koopman ◽

Henk-Jan Visch ◽

Sjoerd Verkaart ◽

Lambertus W. P. J. van den Heuvel ◽

Jan A. M. Smeitink ◽

...

Keyword(s):

Form Factor ◽

Aspect Ratio ◽

Complex I ◽

Mitochondrial Morphology ◽

Nadh:Ubiquinone Oxidoreductase ◽

Mitochondrial Network ◽

Mitochondrial Structure ◽

Complex I Deficiency ◽

Complex I Activity ◽

Human Complex

Complex I (NADH:ubiquinone oxidoreductase) is the largest multisubunit assembly of the oxidative phosphorylation system, and its malfunction is associated with a wide variety of clinical syndromes ranging from highly progressive, often early lethal, encephalopathies to neurodegenerative disorders in adult life. The changes in mitochondrial structure and function that are at the basis of the clinical symptoms are poorly understood. Video-rate confocal microscopy of cells pulse-loaded with mitochondria-specific rhodamine 123 followed by automated analysis of form factor (combined measure of length and degree of branching), aspect ratio (measure of length), and number of revealed marked differences between primary cultures of skin fibroblasts from 13 patients with an isolated complex I deficiency. These differences were independent of the affected subunit, but plotting of the activity of complex I, normalized to that of complex IV, against the ratio of either form factor or aspect ratio to number revealed a linear relationship. Relatively small reductions in activity appeared to be associated with an increase in form factor and never with a decrease in number, whereas relatively large reductions occurred in association with a decrease in form factor and/or an increase in number. These results demonstrate that complex I activity and mitochondrial structure are tightly coupled in human isolated complex I deficiency. To further prove the relationship between aberrations in mitochondrial morphology and pathological condition, fibroblasts from two patients with a different mutation but a highly fragmented mitochondrial phenotype were fused. Full restoration of the mitochondrial network demonstrated that this change in mitochondrial morphology was indeed associated with human complex I deficiency.

Download Full-text

Ca2+-mobilizing agonists increase mitochondrial ATP production to accelerate cytosolic Ca2+removal: aberrations in human complex I deficiency

AJP Cell Physiology ◽

10.1152/ajpcell.00561.2005 ◽

2006 ◽

Vol 291 (2) ◽

pp. C308-C316 ◽

Cited By ~ 22

Author(s):

Henk-Jan Visch ◽

Werner J. H. Koopman ◽

Dimphy Zeegers ◽

Sjenet E. van Emst-de Vries ◽

Frank J. M. van Kuppeveld ◽

...

Keyword(s):

Digital Imaging ◽

Complex I ◽

Removal Rate ◽

Mitochondrial Matrix ◽

Atp Production ◽

Complex I Deficiency ◽

Deficient Patient ◽

Atp Supply ◽

Human Complex

Previously, we reported that both the bradykinin (Bk)-induced increase in mitochondrial ATP concentration ([ATP]M) and the rate of cytosolic Ca2+removal are significantly decreased in skin fibroblasts from a patient with an isolated complex I deficiency. Here we demonstrate that the mitochondrial Ca2+indicator rhod-2 can be used to selectively buffer the Bk-induced increase in mitochondrial Ca2+concentration ([Ca2+]M) and, consequently, the Ca2+-stimulated increase in [ATP]M, thus allowing studies of how the increase in [ATP]Mand the cytosolic Ca2+removal rate are related. Luminometry of healthy fibroblasts expressing either aequorin or luciferase in the mitochondrial matrix showed that rhod-2 dose dependently decreased the Bk-induced increase in [Ca2+]Mand [ATP]Mby maximally 80 and 90%, respectively. Digital imaging microscopy of cells coloaded with the cytosolic Ca2+indicator fura-2 revealed that, in parallel, rhod-2 maximally decreased the cytosolic Ca2+removal rate by 20%. These findings demonstrate that increased mitochondrial ATP production is required for accelerating cytosolic Ca2+removal during stimulation with a Ca2+-mobilizing agonist. In contrast, complex I-deficient patient fibroblasts displayed a cytosolic Ca2+removal rate that was already decreased by 40% compared with healthy fibroblasts. Rhod-2 did not further decrease this rate, indicating the absence of mitochondrial ATP supply to the cytosolic Ca2+pumps. This work reveals the usefulness of rhodamine-based Ca2+indicators in examining the role of intramitochondrial Ca2+in mitochondrial (patho) physiology.

Download Full-text