1. Regulation of Floral-Organ- Type by SUPERMAN 1.Need for regulators of the organ-identity genes. 2.The Superman mutant phenotype-predicting the role of SUPERMAN. 3.Testing our hypothesis of the role of SUPERMAN.

2. Superman Floral Phenotype Wild-type Flower Superman Flower

3. Superman Floral Phenotype SEM

4. Structure of wild type and mutant Arabidopsis flowers Whorl 1Whorl 2 Whorl 3Whorl 4 WTSEPALPETAL STAMENCARPEL AgSEPALPETALPETALSEPAL/ Pi orSEPALSEPALCARPELCARPEL Ap3 Sup Sup/ Pi or Ap3 Sup/ Ag SEPALPETALSTAMENSTAMEN

5. 1 2 3 4 B (AP3, PI) C (AG) sepalpetalstamen carpel A (AP1, AP2) B (AP3, PI) A Model For Control of Organ Type: Sup Mutant

6. Structure of wild type and mutant Arabidopsis flowers Whorl 1Whorl 2 Whorl 3Whorl 4 WTSEPALPETAL STAMENCARPEL AgSEPALPETALPETALSEPAL/ Pi orSEPALSEPALCARPELCARPEL Ap3 Sup Sup/ E Pi or Ap3 O Sup/ E Ag O SEPALPETALSTAMENSTAMEN

7. A Model For Control of Organ Type: Sup Mutant 1 2 3 4 B (AP3, PI) C (AG) sepalpetalstamen carpel A (AP1, AP2) B (AP3, PI)

8. Structure of wild type and mutant Arabidopsis flowers Whorl 1Whorl 2 Whorl 3Whorl 4 WTSEPALPETAL STAMENCARPEL AgSEPALPETALPETALSEPAL/ Pi orSEPALSEPALCARPELCARPEL Ap3 Sup Sup/ E Pi or Ap3 O Sup/ E Ag O SEPALPETALSTAMENSTAMEN SEPALSEPALCARPELCARPEL

9. Sup, Pi Double Mutant Flower PiPi, Sup

10. Structure of wild type and mutant Arabidopsis flowers Whorl 1Whorl 2 Whorl 3Whorl 4 WTSEPALPETAL STAMENCARPEL AgSEPALPETALPETALSEPAL/ Pi orSEPALSEPALCARPELCARPEL Ap3 Sup Sup/ E Pi or O Ap3 Sup/ E Ag O SEPALPETALSTAMENSTAMEN SEPALSEPALCARPELCARPEL

11. 1 2 3 4 B (AP3, PI) C (AG) sepalpetalstamen carpel A (AP1, AP2) B (AP3, PI) A Model For Control of Organ Type: Sup Mutant

12. Structure of wild type and mutant Arabidopsis flowers Whorl 1Whorl 2 Whorl 3Whorl 4 WTSEPALPETAL STAMENCARPEL AgSEPALPETALPETALSEPAL/ Pi orSEPALSEPALCARPELCARPEL Ap3 Sup Sup/ E Pi or O Ap3 Sup/ E Ag O SEPALPETALSTAMENSTAMEN SEPALSEPALCARPELCARPEL SEPALPETALPETALPETAL

13. Sup, Ag Mutant Phenotype Ag Sup, Ag

14. Structure of wild type and mutant Arabidopsis flowers Whorl 1Whorl 2 Whorl 3Whorl 4 WTSEPALPETAL STAMENCARPEL AgSEPALPETALPETALSEPAL/ Pi orSEPALSEPALCARPELCARPEL Ap3 Sup Sup/ E Pi or O Ap3 Sup/ E Ag O SEPALPETALSTAMENSTAMEN SEPALSEPALCARPELCARPEL SEPALPETALPETALPETAL

15. A Model For Control of Organ Type: Sup Mutant 1 2 3 4 B (AP3, PI) C (AG) sepalpetalstamen carpel A (AP1, AP2) B (AP3, PI) AP3 expression?

16. AP3 Expression in the Sup Mutant Wild-type Superman

17. SUP gene Cloned (by position) SUP encodes a transcription factor. Where is SUP expressed?

18. A Model For Control of Organ Type: Sup Mutant 1 2 3 4 B (AP3, PI) C (AG) sepalpetalstamen carpel A (AP1, AP2) B (AP3, PI)

19. SUPERMAN Expression

20. A Model For Control of Organ Type: SUP Expression 1 2 3 4 B (AP3, PI) C (AG) sepalpetalstamen carpel A (AP1, AP2)

21. When SUPERMAN is expressed ectopically using the AP1 promoter all floral organs are reduced or absent. SUPERMAN is also expressed in the ovule integuments and in the Sup mutant the integuments grow too much. A Model For Control of Organ Type: Sup Mutant

22. A Model For Control of Organ Type: SUP Expression 1 2 3 4 B (AP3, PI) C (AG) sepalpetalstamen carpel A (AP1, AP2)

23. A Model For Control of Organ Type: Sup Mutant Superman is believed to limit the growth of Class B/C cells on the inner edge of the third whorl to produce a sharp boundary

24. Control of floral organ identity Reading assignment Coen, E.S. and E.M. Meyerowitz. 1991. The war of the whorls: genetic interactions controlling flower development. Nature 353: 31-37. Ma, H. 1994. The unfolding drama of flower development: recent results from genetic and molecular analyses. Genes and Dev. 8: 745-756. Goto K., Kyozuka J., Bowman J.L. 2001. Turning floral organs into leaves, leaves into floral organs. Curr Opin Genet Dev. 11:449-56. Westhoff et al. Molecular Plant Development:from gene to plant. Chapter 6, 191-208.