Cell Signaling Pathways

SIGNALING PATHWAYS

Intracellular receptors

• Hydrophobic signaling molecules can travel through the plasma membrane (hormones)
• Receptors inside the cell
• Hormone/receptor complex travels to nucleus to bind DNA and promote a response

Membrane-bound receptors

• Receptor bound to membrane with binding site accessible to the extracellular space
• Ligand binds to receptors
• This causes receptor activation which activates further proteins within the cell
• Activated proteins transduce signal eventually leading to either altered gene expression or altered cellular metabolism