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

Huang, H., Ma, H. (February 1997) FON1, an Arabidopsis gene that terminates floral meristem activity and controls flower organ number. Plant Cell, 9 (2). pp. 115-34. ISSN 1040-4651 (Print)

DOI: 10.​1105/​tpc.​9.​2.​115


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.

Item Type: Paper
Uncontrolled Keywords: Arabidopsis/ genetics Meristem/ genetics Mutagenesis Phenotype Plant Proteins/ genetics/physiology Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.
Subjects: organism description > plant > Arabidopsis
organs, tissues, organelles, cell types and functions > tissues types and functions > meristem
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > DNA, RNA structure, function, modification > mutations > mutagenesis
CSHL Authors:
Communities: CSHL labs
Depositing User: Kathleen Darby
Date: February 1997
Date Deposited: 08 May 2014 16:33
Last Modified: 08 May 2014 16:33
PMCID: PMC156905
Related URLs:

Actions (login required)

Administrator's edit/view item Administrator's edit/view item
CSHL HomeAbout CSHLResearchEducationNews & FeaturesCampus & Public EventsCareersGiving