Logo of geneticsGeneticsCurrent IssueInformation for AuthorsEditorial BoardSubscribeSubmit a Manuscript
Genetics. Nov 2002; 162(3): 1457–1468.
PMCID: PMC1462321

Characterization and effects of the replicated flowering time gene FLC in Brassica rapa.


Functional genetic redundancy is widespread in plants and could have an important impact on phenotypic diversity if the multiple gene copies act in an additive or dosage-dependent manner. We have cloned four Brassica rapa homologs (BrFLC) of the MADS-box flowering-time regulator FLC, located at the top of chromosome 5 of Arabidopsis thaliana. Relative rate tests revealed no evidence for differential rates of evolution and the ratios of nonsynonymous-to-synonymous substitutions suggest BrFLC loci are not under strong purifying selection. BrFLC1, BrFLC2, and BrFLC3 map to genomic regions that are collinear with the top of At5, consistent with a polyploid origin. BrFLC5 maps near a junction of two collinear regions to Arabidopsis, one of which includes an FLC-like gene (AGL31). However, all BrFLC sequences are more closely related to FLC than to AGL31. BrFLC1, BrFLC2, and BrFLC5 cosegregate with flowering-time loci evaluated in populations derived by backcrossing late-flowering alleles from a biennial parent into an annual parent. Two loci segregating in a single backcross population affected flowering in a completely additive manner. Thus, replicated BrFLC genes appear to have a similar function and interact in an additive manner to modulate flowering time.

Full Text

The Full Text of this article is available as a PDF (302K).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Altschul SF, Madden TL, Schäffer AA, Zhang J, Zhang Z, Miller W, Lipman DJ. Gapped BLAST and PSI-BLAST: a new generation of protein database search programs. Nucleic Acids Res. 1997 Sep 1;25(17):3389–3402. [PMC free article] [PubMed]
  • Analysis of the genome sequence of the flowering plant Arabidopsis thaliana. Nature. 2000 Dec 14;408(6814):796–815. [PubMed]
  • Axeisson T, Shavorskaya O, Lagercrantz U. Multiple flowering time QTLs within several Brassica species could be the result of duplicated copies of one ancestral gene. Genome. 2001 Oct;44(5):856–864. [PubMed]
  • Bohuon EJ, Ramsay LD, Craft JA, Arthur AE, Marshall DF, Lydiate DJ, Kearsey MJ. The association of flowering time quantitative trait loci with duplicated regions and candidate loci in Brassica oleracea. Genetics. 1998 Sep;150(1):393–401. [PMC free article] [PubMed]
  • Brown JW, Smith P, Simpson CG. Arabidopsis consensus intron sequences. Plant Mol Biol. 1996 Nov;32(3):531–535. [PubMed]
  • Butruille DV, Guries RP, Osborn TC. Linkage analysis of molecular markers and quantitative trait loci in populations of inbred backcross lines of Brassica napus L. Genetics. 1999 Oct;153(2):949–964. [PMC free article] [PubMed]
  • Nadeau JH, Sankoff D. Comparable rates of gene loss and functional divergence after genome duplications early in vertebrate evolution. Genetics. 1997 Nov;147(3):1259–1266. [PMC free article] [PubMed]
  • Doebley J, Lukens L. Transcriptional regulators and the evolution of plant form. Plant Cell. 1998 Jul;10(7):1075–1082. [PMC free article] [PubMed]
  • Nei M, Gojobori T. Simple methods for estimating the numbers of synonymous and nonsynonymous nucleotide substitutions. Mol Biol Evol. 1986 Sep;3(5):418–426. [PubMed]
  • Osborn TC, Kole C, Parkin IA, Sharpe AG, Kuiper M, Lydiate DJ, Trick M. Comparison of flowering time genes in Brassica rapa, B. napus and Arabidopsis thaliana. Genetics. 1997 Jul;146(3):1123–1129. [PMC free article] [PubMed]
  • Force A, Lynch M, Pickett FB, Amores A, Yan YL, Postlethwait J. Preservation of duplicate genes by complementary, degenerative mutations. Genetics. 1999 Apr;151(4):1531–1545. [PMC free article] [PubMed]
  • Osterberg Marita Kruskopf, Shavorskaya Oksana, Lascoux Martin, Lagercrantz Ulf. Naturally occurring indel variation in the Brassica nigra COL1 gene is associated with variation in flowering time. Genetics. 2002 May;161(1):299–306. [PMC free article] [PubMed]
  • Frary A, Nesbitt TC, Grandillo S, Knaap E, Cong B, Liu J, Meller J, Elber R, Alpert KB, Tanksley SD. fw2.2: a quantitative trait locus key to the evolution of tomato fruit size. Science. 2000 Jul 7;289(5476):85–88. [PubMed]
  • Guo M, Davis D, Birchler JA. Dosage effects on gene expression in a maize ploidy series. Genetics. 1996 Apr;142(4):1349–1355. [PMC free article] [PubMed]
  • Huang X. An improved sequence assembly program. Genomics. 1996 Apr 1;33(1):21–31. [PubMed]
  • Purugganan MD, Rounsley SD, Schmidt RJ, Yanofsky MF. Molecular evolution of flower development: diversification of the plant MADS-box regulatory gene family. Genetics. 1995 May;140(1):345–356. [PMC free article] [PubMed]
  • Johanson U, West J, Lister C, Michaels S, Amasino R, Dean C. Molecular analysis of FRIGIDA, a major determinant of natural variation in Arabidopsis flowering time. Science. 2000 Oct 13;290(5490):344–347. [PubMed]
  • Putterill J, Robson F, Lee K, Simon R, Coupland G. The CONSTANS gene of Arabidopsis promotes flowering and encodes a protein showing similarities to zinc finger transcription factors. Cell. 1995 Mar 24;80(6):847–857. [PubMed]
  • Robert LS, Robson F, Sharpe A, Lydiate D, Coupland G. Conserved structure and function of the Arabidopsis flowering time gene CONSTANS in Brassica napus. Plant Mol Biol. 1998 Jul;37(5):763–772. [PubMed]
  • Roose ML, Gottlieb LD. Biochemical properties and level of expression of alcohol dehydrogenases in the allotetraploid plant Tragopogon miscellus and its diploid progenitors. Biochem Genet. 1980 Dec;18(11-12):1065–1085. [PubMed]
  • Sheldon CC, Burn JE, Perez PP, Metzger J, Edwards JA, Peacock WJ, Dennis ES. The FLF MADS box gene: a repressor of flowering in Arabidopsis regulated by vernalization and methylation. Plant Cell. 1999 Mar;11(3):445–458. [PMC free article] [PubMed]
  • Shepard Kristen A, Purugganan Michael D. The genetics of plant morphological evolution. Curr Opin Plant Biol. 2002 Feb;5(1):49–55. [PubMed]
  • Tadege M, Sheldon CC, Helliwell CA, Stoutjesdijk P, Dennis ES, Peacock WJ. Control of flowering time by FLC orthologues in Brassica napus. Plant J. 2001 Dec;28(5):545–553. [PubMed]
  • Lagercrantz U, Axelsson T. Rapid evolution of the family of CONSTANS LIKE genes in plants. Mol Biol Evol. 2000 Oct;17(10):1499–1507. [PubMed]
  • Tajima F. Simple methods for testing the molecular evolutionary clock hypothesis. Genetics. 1993 Oct;135(2):599–607. [PMC free article] [PubMed]
  • Lagercrantz U, Putterill J, Coupland G, Lydiate D. Comparative mapping in Arabidopsis and Brassica, fine scale genome collinearity and congruence of genes controlling flowering time. Plant J. 1996 Jan;9(1):13–20. [PubMed]
  • Thompson JD, Higgins DG, Gibson TJ. CLUSTAL W: improving the sensitivity of progressive multiple sequence alignment through sequence weighting, position-specific gap penalties and weight matrix choice. Nucleic Acids Res. 1994 Nov 11;22(22):4673–4680. [PMC free article] [PubMed]
  • Tiffin Peter, Hahn Matthew W. Coding sequence divergence between two closely related plant species: Arabidopsis thaliana and Brassica rapa ssp. pekinensis. J Mol Evol. 2002 Jun;54(6):746–753. [PubMed]
  • Lynch M, Conery JS. The evolutionary fate and consequences of duplicate genes. Science. 2000 Nov 10;290(5494):1151–1155. [PubMed]
  • Manley NR, Capecchi MR. Hox group 3 paralogous genes act synergistically in the formation of somitic and neural crest-derived structures. Dev Biol. 1997 Dec 15;192(2):274–288. [PubMed]
  • Masterson J. Stomatal size in fossil plants: evidence for polyploidy in majority of angiosperms. Science. 1994 Apr 15;264(5157):421–424. [PubMed]

Articles from Genetics are provided here courtesy of Genetics Society of America


Related citations in PubMed

See reviews...See all...

Cited by other articles in PMC

See all...


Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...