Week 9 Handout - BIBC 100 Week 9 Jonathan Goldstone...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
BIBC 100 Week 9 Jonathan Goldstone [email protected] Signal Transduction Cells must convert extracellular signals into intracellular signals that alter cell behaviour o ie antigens, light, hormones, nutrients, growth factors, neurotransmitters Requirements for signal transduction o Specificity o Amplification o Desensitization/Adaptation o Integration Fig 12-2 – summary slide of signal transduction (you only need to know two types) o G protein- coupled  receptors o Receptor  tyrosine  kinase o Receptor guanylyl cyclase o Adhesion receptor (integrin) Fig 13-1 B and T – example of receptor tyrosine kinase o Extracellular ligand-binding domain and intracellular tyrosine kinase domain o Phosphorylates Tyr residues both in receptor  itself and in target proteins o Structure 2 identical extracellular α-subunits – insulin binding sites 2 β-chains – Tyr kinase activity o Mechanism of action for Insulin receptor Insulin binds and leads to conformational change in receptor Conformational change leads to autoP (crossP) of self Targets 3 Tyr residues on intracellular domain of receptor o Each β-chain phosphorylates the other one Conformational change reveals substrate binding sites o Increases kinase activity of enzyme Phosphorylation of IRS-1 – Insulin Receptor Substrate 1 o Goes on and activates many downstream effects P-Tyr on IRS-1 binds to and activates PI-3 kinase o PI = phosphatidyl inositol o PI-3 kinase converts PIP2 into PIP3 PIP3 binds and activates Protein Kinase B PKB leads to the mobilization of glucose transporters Glycogen synthesis Glycogen synthase kinase (GSK) is inactive when
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
BIBC 100 Week 9 Jonathan Goldstone [email protected] phosphorylated PKB phosphorylates GSK3, therefore inactivating it When glycogen synthase (GS) is phosphorylated, it is inactive When GSK3 is phosphorylated, it cannot phosphorylate GS into its inactive form, therefore GS stays active and makes glycogen!
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern