Mitichondia Flashcards
What processes occur in mitochondria
Produce most of cellular aTP via OXPHOS pathway, location for TCA cycle and parts of urea cycle
How many genes on mitichondria and what do they encode
- There are 13 polypeptides of OXPHOS pathway, 2 rRNA and 22tRNA
Features of mtDNA
No introns, v few non coding bases, increased mutation freq. can be homo or heterodisomy, 16.6kb circular Dna, female inheritance % mutant Dna can vary in family and within individual
What is homoplasmy
Homoplasmy refers to a cell that has a uniform collection of mtDNA: either completely normal mtDNA or completely abnormal
General Phenotype of my disease
Eyes:ptosis, blindness, skeletal, muscle, digestive tract, nervous system - seizures,dd, heart
What is primary mt disease
Gene encoded in mt is mutated
Example of primary Mt disease
Deletions:,Pearson.MDP, A, lactic acidosis, pancreatic unsufficiency. Point mutations: MERFF: myoclonic epilepsy, myopathy, cerebral ataxia
Example of secondary mt disease
- Twinkle/peo1 = direct effect on mt expression, 2. alpers syndrome- indirect effects such as disruption of n transport and salvage and synthesis. 3.Dysregulation without affecting mt Dna: assembly factors surf1
2 types of fertility treatment for mt disease carriers
1.pronuclear transfer: after fertilisation. Parent nuclei teas ferried into donor egg. 2. Maternal spindle transfer: before fertilisation. Remove mat nucleus put into donor egg then fertilise. Feb 2015. U.K. Allow mt ART. 3 person babies!
Considerations for mt ART
Cross talk between diff mt and nDNA haplotypes? Residual transfer of mt. Carry over shown in
What is heteroplasmy
Heteroplasmy is the presence of more than one type of organellar genome (mitochondrial DNA or plastid DNA) within a cell or individual.
