In plants, even miRNAs are generated by Dicer alone; it is not clear how they manage to forgo prior action of Drosha.

TLS Online TPP Program

#Id: 10546

#Unit 4. Cell Communication and Cell Signaling

Apoptosome 

a disk-shaped 1.4-MDa heptameric wheel of death

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#Id: 10547

#Unit 4. Cell Communication and Cell Signaling

Apoptosis of mammalian cells is activated by either: Intrinsic signaling pathways

Extrinsic signaling pathways

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#Id: 10548

#Unit 4. Cell Communication and Cell Signaling

Intrinsic apoptosis pathway is mediated by an activated initiator caspase (caspase-9)

TLS Online TPP Program

#Id: 10549

#Unit 4. Cell Communication and Cell Signaling

Extrinsic apoptosis pathway, is initiated by ligands of death receptor family TNFα and FasL (trimeric ligand)

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#Unit 4. Cell Communication and Cell Signaling

Extrinsic (death receptor–regulated) apoptosis pathway

binding of TNFα to TNFR1, a DD-containing death

receptor, recruits another two DD-containing

signaling molecules, TRADD and RIPK1

TLS Online TPP Program

#Id: 10551

#Unit 4. Cell Communication and Cell Signaling

The activation of RIPK1 kinase is a key decisive event that can initiate cell death by either apoptosis or necroptosis.