1 / 27

Drosophila

variation. Drosophila. Egg chamber. Eggshell (chorion). ?. ?. Y*. The experimental system. Cellular responses. EGFR/ErbB Signaling Network. Invertebrates. Vertebrates. ErbB3. EGFR. ErbB2. EGFR. signal diversification • inhibitors ?. signal diversification: • heterodimerization.

nkirby
Download Presentation

Drosophila

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. variation Drosophila Egg chamber Eggshell (chorion) ? ? Y* The experimental system Cellular responses

  2. EGFR/ErbB Signaling Network Invertebrates Vertebrates ErbB3 EGFR ErbB2 EGFR signal diversification • inhibitors ? signal diversification: • heterodimerization

  3. The EGFR network and dorsal patterning Amplification Spitz Vein Inhibition Argos Site of Appendage Formation chorion Profile of EGFR activity: WT Initiation Gurken

  4. Molecular Genetic Phylogenetic identify targets Create differences = mutant screens Identify differences = other species How can we identify components of the EGFR network?

  5. ligand Kek1 Kek1 and feedback regulation of EGFR EGFR kek1 expression ? No overt phenotype ?

  6. Kek1 overexpression inhibits receptor signaling ligand Kek1 EGFR

  7. WT kek1- WT egfr- egfr-; kek1- BR-C rho aos Evidence that endogenous kek1 inhibits EGFR signaling

  8. Profile of EGFR activity: WT Profile of EGFR activity: kek1- What role does Kek1 have in dorsal patterning? Initiation Gurken Amplification Spitz Vein Inhibition Argos Site of Appendage Formation

  9. Kek1 inhibits EGFR signaling 1. Mechanism 2. Sequence requirements ligand EGFR Kek1 EGFR

  10. Kek1 Kek1 Y* No signaling - ventralized Signaling - dorsalized Kek1 inhibits EGFR signaling 1. Mechanism Ligand sink vs heterodimer EGFR

  11. Kek1 EGFR Kek1 inhibits EGFR signaling 2. Sequence requirements ? Domain swaps

  12. Kek1 inhibits EGFR signaling 2. Sequence requirements ? The Kek1 LRRs are sufficient for binding EGFR… …but insufficient for full inhibition in vivo! L LIT

  13. [GMR-GAL4*] [UAS-kek1*gfp] [GMR-GAL4] [UAS-kek1gfp] ____________________ + ____________________ CyO w; iso2; iso3 EMS EMS Identifying residues important for Kek1/EGFR interaction P suppressor F1

  14. Suppressors of Kek1 = egfr alleles Identifying residues important for Kek1/EGFR interaction Knockouts of Kek1

  15. Kek1 = a novel inhibitory component of the EGFR network Binding & Inhibition Kek1 EGFR Trafficking & Stability

  16. X Mutations in vital gene = lethality Identification of EGFR components Genetic approach Directed mosaics Drosophila Egg chamber dCBP bwk WT

  17. wild type EGFR dCBP pnt dCBP mediates feedback inhibition of EGFR signaling

  18. dCBP - dCBP mediates feedback inhibition of EGFR signaling wt Initiation Gurken Amplification Spitz Vein Inhibition Argos Site of Appendage Formation chorion

  19. amplification inhibition attenuation Rhomboid Kek1 dCBP/Pointed Bwk Argos Egfr mediated epithelial patterning Gurken EGFR Egfr transcriptional targets

  20. Identification of EGFR components 1 4 2 2 3 2 4 L.Throckmorton, 1950 Phylogenetic approach 4 latifasciaformis

  21. EGFR signaling and appendage patterning What components of the pathway underlie variation in dorsal appendage patterning? Intraspecific analysis Interspecific analysis map natural variation Characterize patterning at molecular level dose-dependent screen ? genes

  22. Interspecific analysis: Kek1 A F G B C H D I J E D. melanogaster D. virilis

  23. grkHK36 egfrCO + + Intraspecific analysis • Does quantitative variation in the EGFR network exist? • If so, what molecular components underlie this variation? - template for interspecific variation? Appendage variation WT/V0 V1a V1b V2 V3 V4

  24. Intraspecific variation in EGFR signaling

  25. 3 EGFR signaling and appendage patterning Identifying novel dose-dependent EGFR components grkHK36 egfrCO + +

  26. amplification inhibition attenuation Rhomboid Kek1 dCBP/Pointed Bwk Argos Egfr mediated epithelial patterning Gurken EGFR Egfr transcriptional targets

  27. Acknowledgements Andrea Cowden Omar Hasnie Matt Rubin Kyle Payne Diego Alvarado Alex Doetsch Tim Evans Christina MacLaren Amy Rice Anne Scherer Fred Derheimer Libbie Eakin Paul Miller Christopher Skipwith Brandon Weasner

More Related