6. achaete stade 9stade 10 Lsc Achaete Achaete+Scute Gène proneural Groupe proneural

9. Type normal Mutant iroquois

12. C14

13. Prepattern genes: iroquois etc... Proneural genes: scute etc... Precursor genes: neu, poxn Lineage genes: numb etc... Compartment genes: en, dpp, ap… Lateral inhibition genes: Notch Delta etc... Maternal genes Gap genes Pair-rule genes

16. wild-typeNotch Crible F2

17. wild-typeNotch

18. wild-type Notch achaete

19. Delta Notch DSL EGF-like LNR Ankyrin

20. S2 + Notch + Delta aggrégation

21. Cell autonomy of Notch and Delta wild-type/ wild-type wild-type/ Notch wild-type/ Delta Cell autonomous Cell non-autonomous Heitzler and Simpson, 1991

22. Behaviour of mutant and wild-type cells along clonal borders wild-type/ wild-type 50%-50% Reduced Delta/ wild-type wild-type/ Increased Delta Reduced Notch/ wild-type wild-type/ Increased Notch 0%-100% 100%-0% Cells with a higher level of Notch or a lower level of Delta are more likely to adopt the epidermal fate Heitzler and Simpson, 1991

23. Notch Notch act Artavanis-Tsakonas, Struhl, Young, 1993

24. Receiving cell Notch Extracellular P2: TACE/Kuzbanian Delta 2. Ligand-induced S2 processing Signaling cell

25. Receiving cell Notch CSL HES nucleus Su(H) E(spl) nucleus 4. Nuclear import and transcriptional activation

26. Gènes cibles et boucles de retro-contrôle E(spl) Notch - intra Mastermind Su(H) Achaete-Scute Complex genes Delta E(spl)

27. NotchDelta AS-C

28. NotchDelta AS-C prepattern

29. NotchDelta AS-C fluctuations aléatoires

30. NotchDelta AS-C Neuroblaste (100%) Epidermoblaste

32. Génes de prepattern: iroquois etc... Gènes proneuraux: scute etc... Gènes des précurseurs: neu, poxn Gènes du lignage: numb etc... Génes cardinaux: en, dpp, ap, wg C25