Final answer:
The particular BH3-only pro-apoptotic protein that links the extrinsic and intrinsic pathways of apoptosis is not clearly identified in the references provided.
Step-by-step explanation:
The BH3-only pro-apoptotic protein that acts as the link between the extrinsic and intrinsic pathways of apoptosis is not explicitly provided in the reference information supplied. However, generally in apoptosis, cytochrome C is released from the mitochondria and participates in the intrinsic pathway of apoptosis.
It aids in the formation of the apoptosome, leading to the activation of caspases that execute the cell death program. The death-inducing signaling complex (DISC) formed in the extrinsic pathway also ultimately results in caspase activation. A BH3-only protein would typically be involved in the intrinsic pathway by promoting the release of cytochrome C by influencing the activity of Bcl2 proteins such as Bak and Bax.