1. 9/8/2010 The role of runt, en, and slp in establishing MP cell fate

2. Epidermal regulation of runt, en, slp Wild-typerunt4496 odd en

3. runt, slp, and en are expressed in distinct patterns in the developing midline Stage 9 Stage 11 slp En Runt

4. Delta mutant embryos still specify distinct MP fates slp En Runt

5. Slp1 expression patterns – antibody vs in situ Slp1 En Stage 11Stage 12Stage 14 Stage 11Stage 12Stage 14 Stage 10 slp1 En

6. MP3 assumes an MP4-like fate in slp1 mutant embryos

7. Model RuntSlpEn MP3AMG, MP1MP4, PMG tup

8. Reagent to test this model – Tup – antibody and probe Tup tup En

9. Examine 4 genotypes to test this model sim-Gal4 uas-slp1 sim-Gal4 uas-enVP16 enA/enE transheterozygote runt 4496 null mutant

10. Is slp1 sufficient to induce MP3 formation? RuntSlpEn MP3AMG, MP1MP4, PMG Slp sim-gal4 uas-slp1 tup En sim-gal4 uas-slp1 ple En

11. Is tup a downstream target of engrailed? sim-Gal4 uas-enVP16 enA/enE RuntSlpEn MP3AMG, MP1MP4, PMG tuptup Elav

12. Is tup a downstream target of engrailed? tup Odd

13. RuntSlpEn MP3AMG, MP1MP4, PMG What is the role of En in posterior neurons? Does a transcription factor specify MP4 fate? tup Hh

14. What purpose does en serve in midline neurons? Joe Kearney’s data

15. Variable number of neurons in en mutant embryos From 43 segments: Average number of neurons: 7.2 +- 1.9 Range: 4-10 wor Elav MNB is missing

16. Average number of Zfh1 positive cells (stage 13-15, 9 segments) : 2.8

17. Segment mixing? stage 11 Elav Zfh1 Elav tup Elav Zfh1 Elav Early enA/enE segments are disorganized

18. MP1s are also present in en mutant embryos HbZfh1 tup MP1smVUMs H-cell wor Elav MNBs

19. Examine iVUM and mVUM markers – Lim1, vglut, gad1, tkr, and cas Future en experiments Rescue En in midline and in paired stripes in an enA/enE mutant background Ectopically express En and EnVP16 in all midline neurons – consequences? Drive Runt in midline neurons?

20. MP1 cell fate Stage 9 slp1 En

21. MP1s still form in the absence of either runt or slp1 tup Odd slp1 2 runt4496 en+ segmenten- segment Look at additional MP1 mutant animals to determine mechanisms that establish MP1 cell fate hb En

22. Current Model RuntSlpEn MP3AMG, MP1MP4, PMG tup odd, hb Hh