Mitochondria B Flashcards
ATP synthesis is achieved by the ______ .
inner membrane embedded protein complex known as ATP synthase.
ATP synthase consists from two main parts:.
F1 and F0
F0 protein complex is located:
spannng the inner mitochondria membrane and forms a proton channel
F1 protein complex is
bound to F0 and is an actual enzyme that makes ATP.
F0 function
uses the energy of proton movement through the channel to generate ATP.
How many protons are needed to generate 1 ATP?
3 protons
Once made, ATP is transported out of mitochondria via ______
ATP-ADP antiporter
mitochondria is also involved in regulating ______.
cell death
Cell damage induces _______,
Bak/Bax-dependent permeabilization of outer mitochondria membrane
Cytochrome c binds to several cytpolasmic proteins forming protein complex known as ______.
apoptosome
Apoptosome activates ______
caspases, thus intiating apoptosis (regulated cell death).
During ischemic injury, mitochondria also promotes ______
necrotic cell death.
Ischemic injury results in ______
MPTP-dependent permeabilization of inner and outer mitochondria membranes, resulting in cytochrome release and elimination of proton gradient.
_____ blocks ATP production.
lack of proton gradient
In the absence of proton gradient, ATP synthase is converted into ______
ATPase, thus using up available ATP. That leads to ATP depletion and necrosis.
release of Bak/Bax-dependent permeabilization of outer mitochondria membrane leads to _____
leads to cytochrome c release.
Damaged mitochondria is not only uncapable of producing ____, but also generate excessive amounts of _____.
ATP
reactive oxygen (ROS)
ROS causes _______
cell damage and senescence by oxidating various cellular proteins, lipids and DNA.
As the result, the mitochondria quality s strictly controlled at three levels.
mitochondria control levels:
- several mitochondrial proteases
- mitophagy.
- if mitochondria damage is extensive, mitochondria induces apoptotosis.
mitochondrial proteases: examples and function?
- mAAA
- iAAA
- Lon
responsible for recognizing and degrading mis-folded proteins.
mitophagy
- a way of fixing damaged mitochondria by fusing the damaged mitochondria with healthy mitochondria,
- can also eliminate damaged mitochondria
Accumulation of mitochondria damage and increase in ROS is related to _______.
senescence and increased sensitivity to neuronal degeneration
In addition, several mutations of the proteins in mitochondria quality control pathways result in _____.
various neuropathys
Mutations in mitochondria fusion machinery causes _____
- autosomal dominant optic atrophy (OPA1 gene)
2. Charcot-Marie-Tooth neuropathy type 2A (Mfn2 gene).
autosomal dominant optic atrophy gene?
OPA1 gene
Charcot-Marie-Tooth neuropathy type 2A gene?
Mfn2 gene
Mutation in mAAA protease causes _______.
hereditary spastic paraplegia
arsenic toxin works by:
inhibiting oxidative phosphorylation and inhibiting ATP production.
what mutation causes autosomal dominant optic atophy?
mitchondrial fusion
what mutation causes heteditary spastic paraplegia?
mAAA protease
what mutation causes carchot marie tooth neuropathy?
mitochondrial fusion
mitochondria functions:
- generate ATP
- apoptosis
- regulation of intracellular Ca ion
mutations in Mfn and OPA cause
- autosomal dominant optic atrophy
2. Charcot Marie Tooth neuropathy 2A
role of mitochondria in cell death
- regulation of cytosolic calcium
- generation of ROS
- supply energy
- release of cytochrome c and activation of apoptosome
