Antigen receptors use multiple mechanisms to recruit signaling proteins to the plasma membrane, where they can propagate downstream signals. In some cases, recruitment of proteins to the membrane is induced following antigen receptor stimulation, whereas other proteins are constitutively associated with the membrane.
Name one mechanism that is induced by antigen receptor stimulation, and one that is constitutive, and give an example a protein recruited by each mechanism.

Question

Antigen receptors use multiple mechanisms to recruit signaling proteins to the plasma membrane, where they can propagate downstream signals. In some cases, recruitment of proteins to the membrane is induced following antigen receptor stimulation, whereas other proteins are constitutively associated with the membrane. 
Name one mechanism that is induced by antigen receptor stimulation, and one that is constitutive, and give an example a protein recruited by each mechanism.

Quizplus · Accepted Answer

The Answer is Recruitment induced by antigen receptor stimulation:

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binding to a membrane associated scaffold protein that is phosphorylated in response to antigen receptor stimulation (examples: Grb2, Gads, SLP-76)

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binding to the membrane phospholipid PIP₃ that is generated by phosphorylation of PIP₂ in response to antigen receptor stimulation (examples: Akt, Itk, PLC-

\gamma

)
Recruitment that is constitutive:

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lipid modified proteins that associate constitutively with the plasma membrane (examples: small GTPases such as Ras, Rap1)

Antigen Receptors Use Multiple Mechanisms to Recruit Signaling Proteins to the Plasma