Parkisons Part 2 Flashcards
What happens to dopamine signaling in Parkinson’s disease?
In Parkinson’s disease, the death of dopaminergic neurons leads to a loss of dopamine synthesis and release, disrupting signaling at both pre and postsynaptic terminals.
What is the difference between autophagy and mitophagy?
Autophagy is a general process by which cells degrade and recycle their own components, while mitophagy specifically refers to the degradation of damaged mitochondria.
What is the role of ubiquitin and the proteasome in mitochondrial degradation?
Ubiquitin tags damaged mitochondria for degradation, and the proteasome is a complex that recognizes these tags and breaks down the tagged mitochondria.
How does Parkinson’s disease affect mitochondria?
In Parkinson’s disease, the protein alpha-synuclein can damage mitochondria, causing them to lose their membrane potential and become unhealthy.
How are damaged mitochondria identified for removal?
Proteins like PINK1 and Parkin bind to damaged mitochondria, marking them for degradation through a process called mitophagy.
What is macroautophagy?
Macroautophagy refers to the process of forming autophagosomes to degrade cellular components.
What is the process of removing damaged mitochondria from cells?
- Cell forms autophagosome around damaged mitochondria.
- Autophagosome fuses with lysosome.
- Contents, including mitochondria, are degraded in lysosome.
- Breakdown products can be recycled by the cell.
What are lysosomes?
Lysosomes are membrane-bound organelles containing digestive enzymes. They break down excess cell parts, help destroy viruses and bacteri
What are the roles of the ER in protein synthesis and calcium regulation?
The ER is crucial for translating mRNA into proteins and for storing/regulating calcium, which is essential for neuronal activity.
Why is maintaining intracellular calcium levels important for neurons, and what happens if calcium regulation in the ER fails?
Neurons depend on calcium gradients for activity, with the ER playing a key role in this. Failure to regulate calcium in the ER can disrupt signaling pathways, potentially leading to cell death.
What is the UPR and when is it initiated?
The UPR is a complex signal transduction pathway activated by three sensors there is an accumulation of misfolded or excess proteins leading to ER stress
What are the overall consequences of alpha-synuclein’s interaction with mitochondria in the context of cellular health?
Alpha-synuclein can disrupt mitochondrial dysfunction and trigger the release of factors like calcium and cytochrome c that can lead to mitochondrial dysfunction and cell death.
