The molecular basis of vernalization: the central role of FLOWERING LOCUS C (FLC).
In Arabidopsis, the MADS-box protein encoded by FLOWERING LOCUS C (FLC) is a repressor of flowering. Vernalization, which promotes flowering in the late-flowering ecotypes and many late-flowering mutants, decreases the level of FLC transcript and protein in the plant. This vernalization-induced reduction in FLC transcript levels is mitotically stable and occurs in all tissues. FLC activity is restored in each generation, as is the requirement of a low-temperature exposure for the promotion of flowering. The level of FLC determines the extent of the vernalization response in the promotion of flowering, and there is a quantitative relationship between the duration of cold treatment and the extent of down-regulation of FLC activity. We conclude that FLC is the central regulator of the induction of flowering by vernalization. Other vernalization-responsive late-flowering mutants, which are disrupted in genes that encode regulators of FLC, are late-flowering as a consequence of their elevated levels of FLC.
Sheldon
C C
CC
Commonwealth Scientific and Industrial Research Organization, Division of Plant Industry, G.P.O. Box 1600, Canberra, ACT 2600, Australia.
Rouse
D T
DT
Finnegan
E J
EJ
Peacock
W J
WJ
Dennis
E S
ES
D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D001483:Base Sequence; D003080:Cold Temperature; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000235:genetics*; D015536:Down-Regulation; D026161:MADS Domain Proteins; D010940:Plant Proteins; D030821:Plants, Genetically Modified; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics*
D017931:DNA Primers; D004268:DNA-Binding Proteins; D026161:MADS Domain Proteins; D010940:Plant Proteins; D012333:RNA, Messenger; D014157:Transcription Factors