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223.20 Principles of Cell Signaling

Cell Signaling-Receptors

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Cell Signaling-Receptors: Intracellular

Cell Signaling

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Cell Signaling

Cell Signaling-four general kinds

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Cell Signaling - Contact dependent

Autocrine Signaling

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Cell Signaling - Cell Surface Receptors: Ion-channel linked

Rapid signal Multipass transmembrane channel

protein changes potential

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Cell Signaling - Cell Surface Receptors: G-protein linked

Indirect signal 7-pass transmembrane protein

with conformational change

Cell Signaling - Cell Surface Receptors: Enzyme linked

Ligand binding activates receptors’ catalytic domains

single-pass transmembrane proteins

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223.20 Principles of Cell Signaling

Signal Transduction Cascade

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Signal Transduction Cascade

Cell Signaling-Phosphorylation

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Cell Signaling-Phosphorylation

Two main types of GTP-binding proteins 1.  Large trimeric GTP-

binding proteins (G-proteins) relay messages from G-protein-coupled receptors (next lecture)

2. Monomeric GTP binding proteins that are GTPases (shown here)

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Cell Signaling

Cell Signaling

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Cell Signaling