Skip to main content
NCBI home page
The Plant Cell logoLink to The Plant Cell
. 1997 Feb;9(2):115–134. doi: 10.1105/tpc.9.2.115

FON1, an Arabidopsis gene that terminates floral meristem activity and controls flower organ number.

H Huang 1, H Ma 1
PMCID: PMC156905  PMID: 9061945

Abstract

A novel gene that regulates floral meristem activity and controls floral organ number was identified in Arabidopsis and is designated FON1 (for FLORAL ORGAN NUMBER1). The fon1 mutants exhibit normal vegetative development and produce normal inflorescence meristems and immature flowers before stage 6. fon1 flowers become visibly different from wild-type flowers at stage 6, when the third-whorl stamen primordia have formed. The fon1 floral meristem functions longer than does that of the wild type: after the outer three-whorl organ primordia have initiated, the remaining central floral meristem continues to produce additional stamen primordia interior to the third whorl. Prolonged fon1 floral meristem activity also results in an increased number of carpels. The clavata (clv) mutations are known to affect floral meristem activity. We have analyzed the clv1 fon1, clv2 fon1, and clv3 fon1 double mutants. These double mutants all have similar phenotypes, with more stamens and carpels than either fon1 or clv single mutants. This indicates that FON1 and CLV genes function in different pathways to control the number of third- and fourth-whorl floral organs. In addition, to test for possible interactions between FON1 and other floral regulatory genes, we have constructed and analyzed the relevant double mutants. Our results suggest that FON1 does not interact with TERMINAL FLOWER1, APETALA1, APETALA2, or UNUSUAL FLORAL ORGAN. In contrast, normal LEAFY function is required for the expression of fon1 phenotypes. In addition, FON1 and AGAMOUS both seem to affect the domain of APETALA3 function, which also affects the formation of stamen-carpel chimera due to fon1 mutations. Finally, genetic analysis suggests that FON1 interacts with SUPERMAN, which also regulates floral meristem activity.

Full Text

The Full Text of this article is available as a PDF (4.2 MB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bowman J. L., Drews G. N., Meyerowitz E. M. Expression of the Arabidopsis floral homeotic gene AGAMOUS is restricted to specific cell types late in flower development. Plant Cell. 1991 Aug;3(8):749–758. doi: 10.1105/tpc.3.8.749. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bowman J. L., Sakai H., Jack T., Weigel D., Mayer U., Meyerowitz E. M. SUPERMAN, a regulator of floral homeotic genes in Arabidopsis. Development. 1992 Mar;114(3):599–615. doi: 10.1242/dev.114.3.599. [DOI] [PubMed] [Google Scholar]
  3. Bowman J. L., Smyth D. R., Meyerowitz E. M. Genes directing flower development in Arabidopsis. Plant Cell. 1989 Jan;1(1):37–52. doi: 10.1105/tpc.1.1.37. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Clark S. E., Running M. P., Meyerowitz E. M. CLAVATA1, a regulator of meristem and flower development in Arabidopsis. Development. 1993 Oct;119(2):397–418. doi: 10.1242/dev.119.2.397. [DOI] [PubMed] [Google Scholar]
  5. Drews G. N., Bowman J. L., Meyerowitz E. M. Negative regulation of the Arabidopsis homeotic gene AGAMOUS by the APETALA2 product. Cell. 1991 Jun 14;65(6):991–1002. doi: 10.1016/0092-8674(91)90551-9. [DOI] [PubMed] [Google Scholar]
  6. Gustafson-Brown C., Savidge B., Yanofsky M. F. Regulation of the arabidopsis floral homeotic gene APETALA1. Cell. 1994 Jan 14;76(1):131–143. doi: 10.1016/0092-8674(94)90178-3. [DOI] [PubMed] [Google Scholar]
  7. Huala E., Sussex I. M. LEAFY Interacts with Floral Homeotic Genes to Regulate Arabidopsis Floral Development. Plant Cell. 1992 Aug;4(8):901–913. doi: 10.1105/tpc.4.8.901. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Ingram G. C., Goodrich J., Wilkinson M. D., Simon R., Haughn G. W., Coen E. S. Parallels between UNUSUAL FLORAL ORGANS and FIMBRIATA, genes controlling flower development in Arabidopsis and Antirrhinum. Plant Cell. 1995 Sep;7(9):1501–1510. doi: 10.1105/tpc.7.9.1501. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Irish V. F., Sussex I. M. Function of the apetala-1 gene during Arabidopsis floral development. Plant Cell. 1990 Aug;2(8):741–753. doi: 10.1105/tpc.2.8.741. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Jack T., Brockman L. L., Meyerowitz E. M. The homeotic gene APETALA3 of Arabidopsis thaliana encodes a MADS box and is expressed in petals and stamens. Cell. 1992 Feb 21;68(4):683–697. doi: 10.1016/0092-8674(92)90144-2. [DOI] [PubMed] [Google Scholar]
  11. Jofuku K. D., den Boer B. G., Van Montagu M., Okamuro J. K. Control of Arabidopsis flower and seed development by the homeotic gene APETALA2. Plant Cell. 1994 Sep;6(9):1211–1225. doi: 10.1105/tpc.6.9.1211. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Konieczny A., Ausubel F. M. A procedure for mapping Arabidopsis mutations using co-dominant ecotype-specific PCR-based markers. Plant J. 1993 Aug;4(2):403–410. doi: 10.1046/j.1365-313x.1993.04020403.x. [DOI] [PubMed] [Google Scholar]
  13. Kunst L., Klenz J. E., Martinez-Zapater J., Haughn G. W. AP2 Gene Determines the Identity of Perianth Organs in Flowers of Arabidopsis thaliana. Plant Cell. 1989 Dec;1(12):1195–1208. doi: 10.1105/tpc.1.12.1195. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Levin J. Z., Meyerowitz E. M. UFO: an Arabidopsis gene involved in both floral meristem and floral organ development. Plant Cell. 1995 May;7(5):529–548. doi: 10.1105/tpc.7.5.529. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Mandel M. A., Gustafson-Brown C., Savidge B., Yanofsky M. F. Molecular characterization of the Arabidopsis floral homeotic gene APETALA1. Nature. 1992 Nov 19;360(6401):273–277. doi: 10.1038/360273a0. [DOI] [PubMed] [Google Scholar]
  16. Meyerowitz E. M., Bowman J. L., Brockman L. L., Drews G. N., Jack T., Sieburth L. E., Weigel D. A genetic and molecular model for flower development in Arabidopsis thaliana. Dev Suppl. 1991;1:157–167. [PubMed] [Google Scholar]
  17. Sakai H., Medrano L. J., Meyerowitz E. M. Role of SUPERMAN in maintaining Arabidopsis floral whorl boundaries. Nature. 1995 Nov 9;378(6553):199–203. doi: 10.1038/378199a0. [DOI] [PubMed] [Google Scholar]
  18. Schultz E. A., Haughn G. W. LEAFY, a Homeotic Gene That Regulates Inflorescence Development in Arabidopsis. Plant Cell. 1991 Aug;3(8):771–781. doi: 10.1105/tpc.3.8.771. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Schultz E. A., Pickett F. B., Haughn G. W. The FLO10 Gene Product Regulates the Expression Domain of Homeotic Genes AP3 and PI in Arabidopsis Flowers. Plant Cell. 1991 Nov;3(11):1221–1237. doi: 10.1105/tpc.3.11.1221. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Shannon S., Meeks-Wagner D. R. A Mutation in the Arabidopsis TFL1 Gene Affects Inflorescence Meristem Development. Plant Cell. 1991 Sep;3(9):877–892. doi: 10.1105/tpc.3.9.877. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Smyth D. R., Bowman J. L., Meyerowitz E. M. Early flower development in Arabidopsis. Plant Cell. 1990 Aug;2(8):755–767. doi: 10.1105/tpc.2.8.755. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Weigel D., Alvarez J., Smyth D. R., Yanofsky M. F., Meyerowitz E. M. LEAFY controls floral meristem identity in Arabidopsis. Cell. 1992 May 29;69(5):843–859. doi: 10.1016/0092-8674(92)90295-n. [DOI] [PubMed] [Google Scholar]
  23. Weigel D., Meyerowitz E. M. Activation of floral homeotic genes in Arabidopsis. Science. 1993 Sep 24;261(5129):1723–1726. doi: 10.1126/science.261.5129.1723. [DOI] [PubMed] [Google Scholar]
  24. Weigel D., Meyerowitz E. M. The ABCs of floral homeotic genes. Cell. 1994 Jul 29;78(2):203–209. doi: 10.1016/0092-8674(94)90291-7. [DOI] [PubMed] [Google Scholar]
  25. Wilkinson M. D., Haughn G. W. UNUSUAL FLORAL ORGANS Controls Meristem Identity and Organ Primordia Fate in Arabidopsis. Plant Cell. 1995 Sep;7(9):1485–1499. doi: 10.1105/tpc.7.9.1485. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from The Plant Cell are provided here courtesy of Oxford University Press

RESOURCES