Synthesis and evaluation of supramolecular chemical tools to study and disrupt epigenetic pathways

Description

p-Sulfonatocalix[X]arene (X = 4 and 6) was explored as a host for trimethyllyated lysine. We found by 1H NMR and ITC titrations that p-sulfonatocalix[4]arene (PSC) bound the trimethyllysine amino acid with high affinity and good selectivity over dimethyllysine and similar dimethylated arginines. When trimethyllysine was in the context of a peptide of the histone 3 tail, affinities increased and PSC was up to 20 -fold selective over identical unmethylated peptides.
Multiple scaffolds were synthetically explored as derivatives of PSC. I created five different scaffolds and synthesized a small library of compounds derived from these scaffolds as hosts for a variety of histone 3 peptides containing biologically important post-translationally modified amino acids. This library was tested using a high-throughput indicator displacement assay and I found three hosts that displayed tuned affinities and selectivities for post-translationally modified amino acids we had not previously targeted.
I studied the ability of these synthetically elaborated calix[4]arenes to identify histone PTMs and monitor an enzymatic reaction. I found covalently linked fluorescent calixarenes were able to accomplish this goal. Furthermore, we studied the ability of these calix[4]arenes to disrupt protein-protein interactions that occur between the trimethyllyated lysine on histone tails and proteins that read these sites. I found that these calixarenes could disrupt these interactions between a variety of proteins and trimethyllyated lysine sites.
These calix[4]arenes show promise as chemical tools that could be used to further probe epigenetic pathways in vitro and further work is needed to explore their utility in cellular assays and in vivo. / Graduate / 0490 / 0487 / [e-mail]

Links & Downloads

1. http://hdl.handle.net/1828/5301
2. Allen, H. F.; Daze, K. D.; Shimbo, T.; Lai, A.; Musselman, C. A.; Sims, J. K.; Wade, P. A.; Hof, F.; Kutateladze, T. G., Inhibition of histone binding by supramolecular hosts. Biochemical Journal 2014, 459, 505-512.
3. Beshara, C. S.; Jones, C. E.; Daze, K. D.; Lilgert, B. J.; Hof, F., A Simple Calixarene Recognizes Post-translationally Methylated Lysine. ChemBioChem 2010, 11 (1), 63-66.
4. Daze, K. D.; Hof, F., The Cation-pi Interaction at Protein-Protein Interaction Interfaces: Developing and Learning from Synthetic Mimics of Proteins That Bind Methylated Lysines. Accounts of Chemical Research 2012, 46 (4), 937-945.
5. Daze, K. D.; Jones, C. E.; Lilgert, B. J.; Beshara, C. S.; Hof, F., Determining the effects of salt, buffer, and temperature on the complexation of methylated ammonium ions and methyllysines by sulfonated calixarenes. Canadian Journal of Chemistry 2013, 91 (11), 1072-1076.
6. Daze, K. D.; Ma, M. C. F.; Pineux, F.; Hof, F., Synthesis of New Trisulfonated Calix[4]arenes Functionalized at the Upper Rim, and Their Complexation with the Trimethyllysine Epigenetic Mark. Organic Letters 2012, 14 (6), 1512-1515.
7. Daze, K. D.; Pinter, T.; Beshara, C. S.; Ibraheem, A.; Minaker, S. A.; Ma, M. C. F.; Courtemanche, R. J. M.; Campbell, R. E.; Hof, F., Supramolecular hosts that recognize methyllysines and disrupt the interaction between a modified histone tail and its epigenetic reader protein. Chemical Science 2012, 3 (9), 2695-2699.
8. Minaker, S. A.; Daze, K. D.; Ma, M. C. F.; Hof, F., Antibody-free reading of the histone code using a simple chemical sensor array. Journal of the American Chemical Society 2012, 134 (28), 11674-11680.
9. Simhadri, C.; Daze, K. D.; Douglas, S. F.; Quon, T. T. H.; Dev, A.; Gignac, M. C.; Peng, F.; Heller, M.; Boulanger, M. J.; Wulff, J. E.; Hof, F., Chromodomain antagonists that target the polycomb-group methyllysine reader protein Chromobox homolog 7 (CBX7). Journal of Medicinal Chemistry 2014, 57 (7), 2874-2883.
10. Tabet, S.; Douglas, S. F.; Daze, K. D.; Garnett, G. A. E.; Allen, K. J. H.; Abrioux, E. M. M.; Quon, T. T. H.; Wulff, J. E.; Hof, F., Synthetic trimethyllysine receptors that bind histone 3, trimethyllysine 27 (H3K27me3) and disrupt its interaction with the epigenetic reader protein CBX7. Bioorganic & Medicinal Chemistry 2013, 21 (22), 7004-7010.

Tags

Medicinal Chemistry

Organic Chemistry

Supramolecular Chemistry

Epigenetics

Additional Fields

Identifer	oai:union.ndltd.org:uvic.ca/oai:dspace.library.uvic.ca:1828/5301
Date	28 April 2014
Creators	Daze, Kevin Douglas
Contributors	Hof, Fraser Alan
Source Sets	University of Victoria
Language	English
Detected Language	English
Type	Thesis
Rights	Available to the World Wide Web