Apoptosis

DNA fragmentation

________ is random, or smeared.

Caspases

________: specialized proteases that mediate apoptosis.

Apoptosis

________ is needed to destroy cells.

Cell

________ is phagocytosed, no tissue reaction.

Extrinsic Pathway

________- Signaling through Death Receptors.

Survival factors

________ usually act by binding to cell surface receptors.

Nuclear Lamina

________: leads to fragmentation of nucleus.

inhibitor of a DNAse

A(n) ________: leads to fragmentation of DNA.

cell death

When cells are deprived of survival factors, they activate programmed ________ pathway.

Apoptosis

________ is needed for proper development.

Caspases

specialized proteases that mediate apoptosis

An inhibitor of a DNAse

leads to fragmentation of DNA

Nuclear Lamina

leads to fragmentation of nucleus

Other Cytoskeletal Associated Proteins

leads to disruption of cytoskeleton and cell fragmentation

Intrinsic Pathway

Mitochondrial Mediated Major Pathway in Mammalian Cells

Apoptosome formation

Activation of Initiator Caspase

Extrinsic Pathway

Signaling through Death Receptors

Anti-Apoptotic Factors

death inhibitors

Pro-Apoptotic Factors

death activators

Types of cell death

cell death by injury; cell death by suicide

Necrosis

Cellular swelling

Membranes are broken

ATP is depleted

Cell lyses, eliciting an inflammatory reaction

DNA fragmentation is random, or smeared

In vivo, whole areas of the tissue are affected

Apoptosis

Cellular condensation

Membranes remain intact

Requires ATP

Cell is phagocytosed, no tissue reaction

Ladder-like DNA fragmentation

In vivo, individual cells appear affected

Why should a cell commit apoptosis?

Apoptosis is needed for proper development; Apoptosis is needed to destroy cells

What makes a cell decide to commit to apoptosis?

Withdrawal of positive signals and receiving negative signals

When cells are deprived of survival factors,

they activate programmed cell death pathway