1 / 19

Modeling Effects of Mutants & Drugs on Ras Signaling

This workshop explores the impact of mutants and drugs on the Ras signaling pathway, a key player in cancer development. Learn about the self-sufficiency of cancer cells and the activation of the Ras-MAPK pathway. Discover how Ras is activated and the effects of mutations on its function. Explore the role of prenylation and the disruption caused by drugs. The workshop also covers modeling techniques to accurately depict the pathway and drug effects.

pachecoc
Download Presentation

Modeling Effects of Mutants & Drugs on Ras Signaling

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Modeling the Effects of Mutants and Drugs on the Ras Signaling Pathway RuleBenders Gianluca Arianna Lyle Kingsbury PiotrGauza Lehman College CMACS Workshop, 2014

  2. Self-Sufficiency is a Hallmark of Cancer • Uncontrolled cell proliferation • Cells acquire ability to sustain growth without external growth queues (IGF, PDGF, etc) • MAPK (Ras-Raf-MEK-ERK) Pathway • The gene encoding Ras isoforms is mutated in many human cancers

  3. Ras-MAPK Pathway Normal Ras Pathway becomes self-sufficient  uncontrolled activation of proliferation program

  4. Ras Activation: Guanine Nucleotide Exchange • Ras (Rat Sarcoma) - Small GTPase protein • Active only in GTP-bound form • Activation through facilitated nucleotide exchange from GDP  GTP via GEF (SOS) • Self-regulates via hydrolysis of GTP  GDP – partially dependent on GAP (RASA1)

  5. G12V/G12D Ras Mutations • Mutations to Ras gene destabilize GAP binding and diminish Ras-GAP affinity • Reduced GTP  GDP hydrolysis rate • Overactive RasGTP  MAPK/Proliferation

  6. Prenylation • After transcription, transferase enzymes modify membrane-bound proteins with either a farenyl or geranyl-geranyl lipid moiety. • This prenyl group facilitates the protein’s incorporation into the plasma-membrane and subsequent interactions with other membrane proteins. • Salirasib, farnesylthiosalicylic acid – disrupts Rasprenylation and membrane association

  7. The Model Pathway

  8. Fixing Mutant kcat

  9. Model Accuracy 7 Mass-Action Reactions 7 Mass-Action Reactions2

  10. Effect of Varying SOS

  11. Mutant Effects on Active RasGTP

  12. Drug Effects on Mutant RasGTP

  13. Drug Effects on Mutant RASGTP

  14. 7 Mass-Action Reactions

  15. Modeling the 7 Mass-Action Reactions Model Accuracy

  16. Modeling the 7 Mass-Action Reactions

  17. Varying D

  18. Acknowledgements Nancy Griffeth Naralys Batista Jim Faeder Stephen Redenti DAN, Random, KScience, Modelers

  19. Questions?

More Related