Bergmann’s rule: Populations in colder climates tend to have greater body mass than those in warmer climates.

TLS Online TPP Program

#Id: 10514

#Unit 4. Cell Communication and Cell Signaling

In mammals

XIAP (inhibitor of apoptosis proteins) restrain both initiator and effector caspases

TLS Online TPP Program

#Id: 10515

#Unit 4. Cell Communication and Cell Signaling

XIAP has N-terminal BIR domains: 

BIR2 - binds to and inhibits caspase-3 and caspase-7

BIR3 - binds to and inhibits initiator caspase-9

TLS Online TPP Program

#Id: 10516

#Unit 4. Cell Communication and Cell Signaling

Bax or Bak oligomers leads to the release of SMAC/DIABLOs, from the mitochondrial IMS which binds to XIAP in the cytosol & blocking XIAP from binding to caspases. 

TLS Online TPP Program

#Id: 10517

#Unit 4. Cell Communication and Cell Signaling

Caspases

are so named because they contain a key cysteine residue in the catalytic site and selectively cleave proteins at sites just C-terminal to aspartate residues

TLS Online TPP Program

#Id: 10518

#Unit 4. Cell Communication and Cell Signaling

Caspases function as homodimers with one domain of each stabilizing the active site of the other; they mediate apoptosis by proteolytic cleavage of selected substrates

TLS Online TPP Program

#Id: 10519

#Unit 4. Cell Communication and Cell Signaling

During apoptosis, increasing amounts of phosphatidylserine are found in the exoplasmic leaflet, where it acts as an “eat me” signal