Biosignaling - Sonic Hedgehog (Shh) Signaling Pathway

The video tutorial explains the Hedgehog signaling pathway, crucial in developmental biology, particularly during fetal and embryonic development. It focuses on the Sonic hedgehog protein, part of a family that includes Indian and Desert hedgehog. The tutorial details the pathway's function, emphasizing the inhibition of inhibition mechanism, where the presence of Hedgehog inhibits the patched protein, allowing smoothened to activate Glee proteins, leading to gene transcription. The process involves the maturation and secretion of Hedgehog proteins, highlighting the role of dispatched in secretion and the importance of cilia in smoothened activation.

Which of the following is NOT a type of Hedgehog protein?

• Sonic Hedgehog

• Indian Hedgehog

• Desert Hedgehog

• Ocean Hedgehog

What is the role of the Patched protein in the absence of Hedgehog?

• Inhibits Glee proteins

• Activates Glee proteins

• Inhibits Smoothened

• Activates Smoothened

What must happen to pre-Hedgehog before it can be secreted?

• It must be glycosylated

• It must be palmitoylated

• It must dimerize

• It must be phosphorylated

What is the function of the Dispatched protein?

• Activates Smoothened

• Secretes Hedgehog dimers

• Inhibits Patched

• Binds to Glee proteins

How does Hedgehog binding to Patched affect Smoothened?

• Activates Smoothened directly

• Inhibits Smoothened

• Prevents Smoothened from being inhibited

• Has no effect on Smoothened

What is the result of Glee protein activation?

• Inhibition of Hedgehog target genes

• Activation of Hedgehog target genes

• Degradation of Hedgehog proteins

• Secretion of Hedgehog proteins

What is the primary mechanism of activation in the Hedgehog signaling pathway?

• Dimerization

• Inhibition of inhibition

• Direct activation

• Phosphorylation