Apoptosis/Necrosis

DNA damage and cell stress can lead to what type of cell death?

Apoptosis

Which cell death is individual?

Apoptosis

Which cell death is programmed?

Apoptosis

What are the two types of cell deaths

Apoptosis and Necrosis

What is the difference between Apoptosis and Necrosis?

Apoptosis have DNA breaks. Necrosis cells ruptures.

Examples of TUNEL assays?

BrdU

Which cell death promotes cancer cell proliferation?

Cancer cells lose the ability to breakdown cellular abnormalities; the cell cannot program itself to commit cell suicide, therefore the cell keeps dividing. The more it divides, the more the mutation becomes aberrant.

What is another name for Procaspase?

Effector Caspases

What is another name for Caspases?

Executioner caspases

Examples of Fluorescent markers for apoptotic cell DNA breaks?

FITC

How can lysosome rupture lead to cell death?

Hydroxyl radicals can damage the lipid tails in the bilayer causing spaces that the enzymes, which can degrade, can go through- leak out. This causes Necrosis cell death, and degrade other cellular structures surrounding the ruptured cell.

Apoptosis has _____ & ______ triggers, and they each can trigger the activation of ______.

Intrinsic and Extrinsic triggers. They trigger the activation of Caspases.

Which form is inactivated: Caspase or Procaspase? How do they separate?

Procaspase. They separate when the procaspase is cleaved by other caspases.

Where are procaspase and caspase found within the cell? What is the specific number?

The Plasma membrane where the killer lymphocytes are bound and all throughout the cytoplasm. procaspase and caspase 8.

What happens to the contents of the cell during apoptosis, and what happens to the cell afterwards?

The cellular contents of the cell stay within the cell and the cell is then phagocytized leaving the surrounding cells uncompromised.

Explain the extrinsic activation of apoptosis!

The extrinsic part of apoptosis begins when a KILLER LYMPHOCYTE attaches itself to a neighboring cell with its Fas receptor onto the neighboring cell's FAS DEATH RECEPTOR. This interaction causes the FADD within the cell (the cell that is not the lymphocyte)- which has a death domain and a death effector domain- to attach the procaspase 8 to the plasma membrane using the appropriate domain attachments. When the procaspase 8 is attached the procaspase dimerizes and forms the executioner caspase (the active form). The KILLER LYMPHOCYTE then separates itself and the cell then goes through apoptosis.

How are initiator caspases created?

They are created when procaspaces cleave each other and undergo dimerazation (two monomers come together to create a dimer). After dimerization the active caspase is born.

How does a fetus' hand form?

Through carefully programmed cell death of apoptosis which sculpts the spaces between the fingers.

How does Necrosis occurs?

Through cell membrane damage. An example is lysosomal breakage. Lysosomes contain various degrading enzymes and the enzymes leak out the cell, and the degradation of the surrounding cells.

For now, what ways can procaspases become active?

Through dimerization, and when hydrolized. Both create caspases.

How does apoptosis happen Intrinsically?

When there is a cell DNA lesion, ATM is activated. ATM causes the activation of a Tumor suppressant P53, which activates BAX. Bax creates openings in the mitochondria which allows Cytochrome C to leak out. Cytochrome C binds to a procaspase which then destroys a lot of proteins. This causes the cell to program its death.

Are cleaved dimers active? Why?

Yes they are because these dimers that are formed through dimerization are two procaspase monomeres joined together, after cleaving each other, to create an initiator caspase, the active form.

Can Apoptotic cells fluorescence? If so, how?

Yes, apoptotic cells fluoresce. The breaks of the DNA can bind to TUNEL assays, which can be marked by Fluorescent markers.

What is Fas and what does it do?

A protein secreted by the surface of the cell of a KILLER LYMPHOCYTE. It binds to its respective FAS DEATH RECEPTOR on a neighboring cell.

Which cell death causes inflammation?

Necrosis

Which cell death has the cell bursting?

Necrosis

Can Apoptotic cells uptake TB dye?

No, only Necrotic cells can uptake TB dye, because the cells rupture and opens up.