Insulin Signaling Cascade and Downstream Effects - Biochemistry Lesson

The video explains the insulin signaling cascade, starting with insulin production in the pancreas and its role in regulating blood glucose levels. It details the structure and activation of insulin receptors, the involvement of IRS and PI3K in the signaling pathway, and the formation of PIP3 leading to AKT activation. The process of glucose transport into cells and glycogen synthesis is covered, along with the activation of mTORC1 and feedback inhibition mechanisms. The video concludes with the effects of insulin dislodgement on glucose transport.

Where is insulin produced in the body?

• Stomach

• Kidneys

• Pancreas

• Liver

What is the structure of the insulin receptor?

• Tetrameric

• Heterotrimeric

• Dimeric

• Monomeric

Which protein regulates the phosphorylation of IRS?

• P-10

• PDK1

• GSK 3

• mTORC1

What does PI3K convert PIP2 into?

• PIP5

• PIP3

• PIP4

• PIP1

Which proteins are recruited to the plasma membrane by PIP3?

• GSK 3 and AS160

• PDK1 and AKT

• IRS and PI3K

• mTORC1 and P76K

What is the role of AS160 in glucose transport?

• Dephosphorylates IRS

• Phosphorylates AKT

• Inhibits GLUT4 translocation

• Activates GLUT4 translocation

How does AKT affect glycogen synthesis?

• Inhibits glycogen synthase

• Activates glycogen synthase

• Inhibits GSK 3

• Activates GSK 3

What complex does AKT activate that is involved in protein synthesis?

• PI3K

• mTORC1

• IRS

• PDK1

What is the effect of P76K on IRS?

• Activates IRS

• Inhibits IRS

• Phosphorylates IRS on tyrosine

• Dephosphorylates IRS

What happens to GLUT4 when insulin is removed from the receptor?

• Remains in the plasma membrane

• Is degraded

• Is secreted out of the cell

• Is stored in vesicles