FRIGIDA-ESSENTIAL 1 interacts genetically with FRIGIDA and FRIGIDA-LIKE 1 to promote the winter-annual habit of Arabidopsis thaliana.
Studies of natural variation have revealed that the winter-annual habit of many accessions of Arabidopsis is conferred by two genes, FRIGIDA (FRI) and FLOWERING LOCUS C (FLC), whose activities impose a vernalization requirement. To better understand the mechanism underlying the winter-annual habit, a genetic screen was performed to identify mutants that suppress the late-flowering behavior of a non-vernalized winter-annual strain. We have identified a locus, FRIGIDA-ESSENTIAL 1 (FES1), which, like FRI, is specifically required for the upregulation of FLC expression. FES1 is predicted to encode a protein with a CCCH zinc finger, but the predicted sequence does not otherwise share significant similarity with other known proteins. fes1 is a complete suppressor of FRI-mediated delayed flowering, but has little effect on the late-flowering phenotype of autonomous-pathway mutants. Thus, FES1 activity is required for the FRI-mediated winter-annual habit, but not for the similar phenotype resulting from autonomous-pathway mutations. Epistasis analysis between FES1, FRI and another specific suppressor of FRI-containing lines, FRIGIDA-LIKE 1 (FRL1), indicates that these genes do not function in a linear pathway, but instead act cooperatively to promote the expression of FLC.
Schmitz
Robert J
RJ
Laboratory of Genetics, University of Wisconsin, Madison, WI 53706, USA.
Hong
Lewis
L
Michaels
Scott
S
Amasino
Richard M
RM
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000378:metabolism / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000502:physiology*; D002352:Carrier Proteins / Q000235:genetics / Q000502:physiology*; D004843:Epistasis, Genetic; D035264:Flowers / Q000235:genetics / Q000502:physiology*; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D012621:Seasons; D016335:Zinc Fingers
D029681:Arabidopsis Proteins; D002352:Carrier Proteins; C521854:FES1 protein, Arabidopsis; C414613:FRI protein, Arabidopsis; C518088:FRL1 protein, Arabidopsis