Characterization and Effects of the Replicated Flowering Time Gene FLC in Brassica rapa

Corresponding author: Thomas C. Osborn, 1575 Linden Dr., University of Wisconsin, Madison, WI 53706., tcosborn{at}facstaff.wisc.edu (E-mail)

Communicating editor: A. PATERSON

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.

This article has been cited by other articles:

				Y. Long, J. Shi, D. Qiu, R. Li, C. Zhang, J. Wang, J. Hou, J. Zhao, L. Shi, B.-S. Park, et al. Flowering Time Quantitative Trait Loci Analysis of Oilseed Brassica in Multiple Environments and Genomewide Alignment with Arabidopsis Genetics, December 1, 2007; 177(4): 2433 - 2444. [Abstract] [Full Text] [PDF]

				P. Lou, J. Zhao, J. S. Kim, S. Shen, D. P. Del Carpio, X. Song, M. Jin, D. Vreugdenhil, X. Wang, M. Koornneef, et al. Quantitative trait loci for flowering time and morphological traits in multiple populations of Brassica rapa J. Exp. Bot., November 28, 2007; (2007) erm255v1. [Abstract] [Full Text] [PDF]

				R. T. Gaeta, J. C. Pires, F. Iniguez-Luy, E. Leon, and T. C. Osborn Genomic Changes in Resynthesized Brassica napus and Their Effect on Gene Expression and Phenotype PLANT CELL, November 1, 2007; 19(11): 3403 - 3417. [Abstract] [Full Text] [PDF]

				T. Slotte, K. Holm, L. M. McIntyre, U. Lagercrantz, and M. Lascoux Differential Expression of Genes Important for Adaptation in Capsella bursa-pastoris (Brassicaceae) Plant Physiology, September 1, 2007; 145(1): 160 - 173. [Abstract] [Full Text] [PDF]

				J. A. Udall and J. F. Wendel Polyploidy and Crop Improvement Crop Sci., November 1, 2006; 46(Supplement_1): S-3 - S-14. [Abstract] [Full Text] [PDF]

				J. S. Kim, T. Y. Chung, G. J. King, M. Jin, T.-J. Yang, Y.-M. Jin, H.-I. Kim, and B.-S. Park A Sequence-Tagged Linkage Map of Brassica rapa Genetics, September 1, 2006; 174(1): 29 - 39. [Abstract] [Full Text] [PDF]

				T.-J. Yang, J. S. Kim, S.-J. Kwon, K.-B. Lim, B.-S. Choi, J.-A Kim, M. Jin, J. Y. Park, M.-H. Lim, H.-I. Kim, et al. Sequence-Level Analysis of the Diploidization Process in the Triplicated FLOWERING LOCUS C Region of Brassica rapa PLANT CELL, June 1, 2006; 18(6): 1339 - 1347. [Abstract] [Full Text] [PDF]

				M. A. Beilstein, I. A. Al-Shehbaz, and E. A. Kellogg Brassicaceae phylogeny and trichome evolution Am. J. Botany, April 1, 2006; 93(4): 607 - 619. [Abstract] [Full Text] [PDF]

				L. N. Lukens, J. C. Pires, E. Leon, R. Vogelzang, L. Oslach, and T. Osborn Patterns of Sequence Loss and Cytosine Methylation within a Population of Newly Resynthesized Brassica napus Allopolyploids Plant Physiology, January 1, 2006; 140(1): 336 - 348. [Abstract] [Full Text] [PDF]

				S.-I Lin, J.-G. Wang, S.-Y. Poon, C.-l. Su, S.-S. Wang, and T.-J. Chiou Differential Regulation of FLOWERING LOCUS C Expression by Vernalization in Cabbage and Arabidopsis Plant Physiology, March 1, 2005; 137(3): 1037 - 1048. [Abstract] [Full Text] [PDF]

				J. A. Udall, P. A. Quijada, and T. C. Osborn Detection of Chromosomal Rearrangements Derived From Homeologous Recombination in Four Mapping Populations of Brassica napus L. Genetics, February 1, 2005; 169(2): 967 - 979. [Abstract] [Full Text] [PDF]

				M. E. Schranz and T. C. Osborn De novo variation in life-history traits and responses to growth conditions of resynthesized polyploid Brassica napus (Brassicaceae) Am. J. Botany, February 1, 2004; 91(2): 174 - 183. [Abstract] [Full Text] [PDF]

				I. M. L. Somorjai, R. G. Danzmann, and M. M. Ferguson Distribution of Temperature Tolerance Quantitative Trait Loci in Arctic Charr (Salvelinus alpinus) and Inferred Homologies in Rainbow Trout (Oncorhynchus mykiss) Genetics, November 1, 2003; 165(3): 1443 - 1456. [Abstract] [Full Text] [PDF]

				F. Foucher, J. Morin, J. Courtiade, S. Cadioux, N. Ellis, M. J. Banfield, and C. Rameau DETERMINATE and LATE FLOWERING Are Two TERMINAL FLOWER1/CENTRORADIALIS Homologs That Control Two Distinct Phases of Flowering Initiation and Development in Pea PLANT CELL, November 1, 2003; 15(11): 2742 - 2754. [Abstract] [Full Text] [PDF]

				L. Lukens, F. Zou, D. Lydiate, I. Parkin, and T. Osborn Comparison of a Brassica oleracea Genetic Map With the Genome of Arabidopsis thaliana Genetics, May 1, 2003; 164(1): 359 - 372. [Abstract] [Full Text] [PDF]