Mitochondria Flashcards
Role of Acetyl-CoA in Krebs cycle
Keeps krebs cycle going to generate NADH and FADH2
What is complex I
NADH dehydrogenase
What is complex II
Succinate dehydrogenase
What is complex III
Ubiquinone- cytochrome C reductase
What is complex IV
Cytochrome c oxidase
What is technically complex v
ATP synthase
What are the small handlers of electrons in ETC
Ubiquinone, semiquinone, ubiquinol and cytC
Where are ATP synthases localised>
Cristae ridges (dimer rows)
Where are the proton pumps of ETC localted?
Membrane regions on either side of dimer rows of the cristae
What are caspases?
Cysteine aspartate proteases
What are the initator capsases
Caspase 9 and 8
What are effector caspases
Caspase 3 and 7
What are caspases activated by
Molecular crowding and proteolysis
What pathways is apoptosis triggered by
Intrinsic and extrinsic
CytC undergoes what following MOMP
Release of cytC following mitochondrial outer membrane permeabilisation
What does BCL-2 protein family control
Formation of pore in outer mitochondrial membrane
What caspase is involved in the intrinsitc apoptopic pathway?
Caspase 9
What is mitophagy?
Selective elimination of mitochondria through autophagy
Is mitophagy ubiquitin dependent?
Yes but it doesn’t have to be
What are primary mitochondrial disorders?
Hetergeneous group of disorders by mutations in genes coding for the mitochondiral respiratory chain and related proteins
What occurs on a molecular level of primary mitochondrial disorders?
Low ATP production leafs to lactic acidosis
What is the most common mitochondiral inherited disease?
Leber’s hereditary optic neuropathy
What is Leber’s hereditary optic neuropathy caused by?
Degeneration of retinal ganglion cells ccausing acute central vision loss.
What mtDNA mutations cause Leber’s hereditary optic neuropathy?
ND1, ND4 and ND6 genes encoding complex I subunits
What are retinal ganglion cells sensitive to
Increased reactibe oxygen species following complex I dysfunction
What is Kearn-Sayre Syndrome caused by?
Deletions of large fragments of mtDNA
Symptoms of Kearn-Sayre syndrome?
Limited eye movement and eyelid droop. Hearing loss, cardiac conduction defects
What are the symptoms of ragged muscle fibre syndromes?
Myopathy, arrythmias, hearing and vision loss, dementia
What mutation causes ragged muscle fibre syndromes
Defective mtDNA genome translation
What is an example of secondary mitchondrial disorders?
Sporafic Parkinson’s disease (complex I impairement)
