Introduction
This is a sample scene created with SAT to by Group, and another to make of the protein.
Introduction guide line: Glycogen Synthase Kinase-3 (GSK-3)
1. Begin with "GSK-3 is serine/threonine protein kinase..." explain what that is (structure and general function)
2. Speak about GSK-3 alpha and GSK-3 beta.
3. Begin to describe green screen in relation to the general structure of serine/threonine protein kinase --> specific differences in GSK-3
4.Talk about which species contain GSK-3
i. Speak about where in which species bodies GSK-3 is present versus humans
ii. Explain function in different species structures versus humans
5. Talk about interactions with other molecules and effects of these interactions.
i. Effects of changing concentrations of GSK-3 and effects of changing the concentrations of molecules it interacts with
ii. Talk about potential effects of mutations
6. Lead previous section (effects of varying amounts and interactions) into diseases caused by GSK-3. Talk about potential therapeutic uses of it and new treatments under research.
Green Screen Caption: Show GSK-3 alpha and GSK-3 beta (if possible?)
Overall Structure
-GSK-3beta has the typical two-domain kinase fold with a beta strand domain at the N-terminal end and an alpha-helical domain at the C-terminal end
-The ATP-binding site is at the interface of the alpha-helical and beta-strand domain and is bordered by the glycine-rich loop and the hinge
-The activation loop runs along the surface of the substrate binding groove
-The C-terminal residues are outside the core kinase fold and form a small domain that packs against the alpha-helical domain
-The beta-strand domain consists of seven antiparallel beta-strands
-Two phosphorylation sites that influence the catalytic activity of the protein
Haar, Ernst ter., Coll, Joyce T., Austen, Douglas A., Hsiao, Hsun-Mei., Swenson, Lora., Jain, Jugnu. Structure of GSK3B reveals a primed phosphorylation mechanism. Vertex Pharmaceuticals Incoprporated, Cambridge MA. Nature Publishing Group, Vol 8 No 7. July 2001.
-Monomer
-Overall structures of the enzyme are similar to that of the apoenzyme
-The crystals contain two molecules of GSK-3beta in the asymmetric unit and the two molecules are treated as identical
-Glycogen Synthase Kinase-3 (GSK-3) is a serine/threonine protein kinase
-Both isoforms have a conserved N-terminal serine reside (S21 for alpha and S9 for beta)
-Phosphorylation of the N-terminal serine residue plays an important role for further activity
Mishra, Nibha et al. Structure based virtual screening of GSK-3beta: Importance of protein flexibility and induced fit, 2009. Bioorganic & Medicinal Chemistry Letters, 2009, Vol. 19 Iss. 19, pp. 5582-5585. Retreived from http://www.sciencedirect.com/science/article/pii/S0960894X09011780
Binding Interactions
1)Folding of protein
a) location and description of position of alpha and beta sheets (Show in separate color on green screen)
b) crystal structure data (Table 1, Structural Characterizaiton of the GSK-3B Active Site Using Selective and Non-selective ATP-mimetic Inhibitors)
2)Substrate binding
a) “phosphate-binding” pocket: describe three crucial basic residues (Show in different color on green screen)
b) GSK-3 substrates and binding specifics- S/TxxxS/T (S=Serine, T=threonine, X= any amino acid)
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3217193/
http://www.rcsb.org/pdb/explore/explore.do?pdbId=1Q3D
Additional Features
1. Difference that can be observed from complexes of Staurosporine with GSK-3 beta and other protein kinases such as CDK2, Chk1, Lck and PKA
+ In GSK-3 beta complex with Staurosporine, water is a part of a hydrogen-bonding network
+ Only direct hydrogen bonds are observed between GSK-3 beta and Staurosporine
2. Comparison of GSK-3 beta complexes with Staurosporine and other inhibitors (AMP-PNP, indirubin-3'-monoxime)
+ Between GSK-3 beta complex with Stauroporine and AMP-PNP, the position of N-terminal domain varies.
+ The angle of binding in the active site are different
+ Water is also used as intermediate in hydrogen bonding in GSK-3 beta complex with Indirubin-3'-monoxime (same with complex in Staurosporine )
http://www.sciencedirect.com.silk.library.umass.edu/science/article/pii/S0022283603010593
Quiz Question 1
GSK-3 beta has various inhibiters; one example is AMP-PMP. These inhibitors bind to the N-terminus of the ligand on the GSK-3 beta complex, a result of the classical binding mechanism for a protein kinase. However, in the case of staurosporine (another inhibitor), it is unable to classically bind to the N-terminus of the ligand on the GSK-3 beta complex. This is because, in a GSK-3 beta complex with staurosporine, the ligand in question has an incompatible angle at the N-terminus, thus failing to undergo classical binding.
What type of bonding does GSK-3 beta exhibit with staurosporine, and which of its residues form this type of bond? A green screen of the complex as well as a lewis structure of the staurosporine molecule are found below, if needed.
Quiz Question 2
What are the locations of the active sites with respect to the two isoforms?
These green screens may help you.
| Amino Terminus |
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Carboxy Terminus |
Answer: At the N and C terminal lobes.
J.A. Bertrand, S. Thieffine, A. Vulpetti, C. Cristiani, B. Valsasina, S. Knapp, H.M. Kalisz, M. Flocco, Structural Characterization of the GSK-3β Active Site Using Selective and Non-selective ATP-mimetic Inhibitors, Journal of Molecular Biology, Volume 333, Issue 2, 17 October 2003, Pages 393-407, ISSN 0022-2836, http://dx.doi.org/10.1016/j.jmb.2003.08.031.
(http://www.sciencedirect.com/science/article/pii/S0022283603010593)
See Also
Credits
Introduction - Zachary Plourde
Overall Structure - Sarah Johnson
Binding Interactions - Christina Lincoln
Additional Features - Bach Pham & Elvan Cevac
Quiz Question 1 - Nerses Haroutunian
Quiz Question 2 - Nick H-K
References
