JK2

Signal Transduction - Cell Surface Receptor

Monomers that are activated sandwiching a hormone

Janus Kinase 2 (JAK2)

Fundamentals:

• Receptor binding leads to quaternary structures unlike the typical tertiary

Primary Messenger:

• Growth Hormone

Mechanism

• Monomer has a extracellular receptor and intracellular domain
• Unactivated Janus Kinase 2 (JAK2)
• Monomeric hormone binds to two receptor molecules
  • Dimer of domains (extracellular/intracellular) is formed
• Activated by cross phosphorylation
• Can phosphorylate substates:
  • Gene expression Signal Transducers and Activators of Transcription (STAT5)
    • Binds to the DNA binding sites to regulate gene expression