Flashcards in Test 2, 17. mitochondrial genetics Deck (18):
What feature makes mitochondria dynamic?
1. mitochondria associate with microtubular cytoskeleton
2. also interact with ER and fuse with other organelles
What changes when mitochondria are in high energy cells?
1. loss of dynamic; become more fixed
2. pack tightly between myofibrils and around sperm flagellum
What is the path that mitochondria evolved from?
1. bacteria--> photosynthesis--> cellular respiration
2. also evolved to retain own DNA
What is the major driving force for fission or fusion?
1. energy needs of the cell.
What is fission?
1. division of the mitochondria
2. activated during times of high stress
What is fusion?
1. joining together of mitochondria
2. helps maintain cell survival and helps fix damaged mitochondria.
What is the protein required for the fission of the mitochondria?
What amount of GTP is required for fusion of mitochondria?
1. outer membrane requires a small amount of GTP
2. Inner membrane fusion requires higher amounts of GTP due to increased amount of transmembrane proteins
What do most mitochondrial mutations affect?
1. tRNA aminoacylation
What is the Mother's curse?
1. accumulation of mitochondrial genomes that are harmful to men but can be neutral or beneficial to females
What are the most common compounds that will damage the mitochondria and increase the rate of aging?
1. ROS. From the respiratory chain damages the mtDNA, which reduces the DNA replication and repair mechanisms.
2. ROS increase with age
3. most common in brain due to high amount of aerobic respiration
What is parkinson's disease?
1. progressive neurodegenerative disease that results in disrupted motor function
2. loss of dopaminergic signaling in the midbrain and this contributes to reduced information processing
What is most likely to contribute to memory loss and dementia associated with the late stages of PD?
1. loss of dopamine signaling
What are the effects of losing dopaminergic neurons, that forms lewy bodies?
1. alpha-synuclein which becomes insoluble aggregates
Familial PD is caused from what?
- mutations associated with linkage analysis
- autosomal recessive or dominant
How does sporadic PD differ from familial?
1. subject to genetic susceptibility and environmental factors
2. affect mitochondrial aspects such as bioenergetics, dynamics, transport and quality control
What are proteins that can lead to mitochondrial cell damage or death?