Flowering Locus C

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Flowering Locus C [1] (FLC) is a MADS-box gene that in late-flowering ecotypes of the plant Arabidopsis thaliana is responsible for vernalization. In a new seedling FLC is expressed, which prevents flowering. Upon exposure to cold, less FLC is expressed (to a degree depending on the amount of cold), and flowering becomes possible. [2] FLC is extensively regulated through epigenetic modifications and transcriptional control.

The expression of FLC is affected by other genes including FLK , [3] FCA [4] and VERNALIZATION2 (VRN2). [4]

Wild Arabidopsis plants have different alleles for the FLC gene, which correspond to ecotypes which either (a) flower rapidly and produce a number of generations during one summer (summer-annual), or (b) flower only after vernalization (winter-annual or late-flowering). This kind of variation can also be provided by variation in the FRIGIDA (FRI) gene. [5]

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References

  1. Michaels SD, Amasino RM (1999), "FLOWERING LOCUS C encodes a novel MADS domain protein that acts as a repressor of flowering", Plant Cell, 11 (5): 949–56, doi:10.1105/tpc.11.5.949, PMC   144226 , PMID   10330478.
  2. Sheldon, Cc; Rouse, Dt; Finnegan, Ej; Peacock, Wj; Dennis, Es (Mar 2000), "The molecular basis of vernalization: the central role of FLOWERING LOCUS C (FLC).", Proceedings of the National Academy of Sciences of the United States of America, 97 (7): 3753–8, doi: 10.1073/pnas.060023597 , PMC   16312 , PMID   10716723
  3. Lim, Mh; Kim, J; Kim, Ys; Chung, Ks; Seo, Yh; Lee, I; Kim, J; Hong, Cb; Kim, Hj; Park, Cm (Mar 2004), "A new Arabidopsis gene, FLK, encodes an RNA binding protein with K homology motifs and regulates flowering time via FLOWERING LOCUS C.", The Plant Cell, 16 (3): 731–40, doi:10.1105/tpc.019331, PMC   385284 , PMID   14973162
  4. 1 2 Sheldon, C. C.; Conn, AB; Dennis, ES; Peacock, WJ (2002), "Different Regulatory Regions Are Required for the Vernalization-Induced Repression of FLOWERING LOCUS C and for the Epigenetic Maintenance of Repression", The Plant Cell Online, 14 (10): 2527–37, doi:10.1105/tpc.004564, PMC   151233 , PMID   12368502
  5. Michaels, Sd; He, Y; Scortecci, Kc; Amasino, Rm (Aug 2003), "Attenuation of FLOWERING LOCUS C activity as a mechanism for the evolution of summer-annual flowering behavior in Arabidopsis", Proceedings of the National Academy of Sciences of the United States of America, 100 (17): 10102–7, Bibcode:2003PNAS..10010102M, doi: 10.1073/pnas.1531467100 , PMC   187779 , PMID   12904584