Contrasting Evolutionary Forces in the Arabidopsis thaliana Floral Developmental Pathway

Corresponding author: Michael D. Purugganan, Department of Genetics, North Carolina State University, Raleigh, NC 27695., michael_purugganan{at}ncsu.edu (E-mail)

Communicating editor: M. K. UYENOYAMA

The floral developmental pathway in Arabidopsis thaliana is composed of several interacting regulatory genes, including the inflorescence architecture gene TERMINAL FLOWER1 (TFL1), the floral meristem identity genes LEAFY (LFY), APETALA1 (AP1), and CAULIFLOWER (CAL), and the floral organ identity genes APETALA3 (AP3) and PISTILLATA (PI). Molecular population genetic analyses of these different genes indicate that the coding regions of AP3 and PI, as well as AP1 and CAL, share similar levels and patterns of nucleotide diversity. In contrast, the coding regions of TFL1 and LFY display a significant reduction in nucleotide variation, suggesting that these sequences have been subjected to a recent adaptive sweep. Moreover, the promoter of TFL1, unlike its coding region, displays high levels of diversity organized into two distinct haplogroups that appear to be maintained by selection. These results suggest that patterns of molecular evoution differ among regulatory genes in this developmental pathway, with the earlier acting genes exhibiting evidence of adaptive evolution.

This article has been cited by other articles:

				H. Ramsay, L. H. Rieseberg, and K. Ritland The Correlation of Evolutionary Rate with Pathway Position in Plant Terpenoid Biosynthesis Mol. Biol. Evol., May 1, 2009; 26(5): 1045 - 1053. [Abstract] [Full Text] [PDF]

				R. Jovelin, J. P. Dunham, F. S. Sung, and P. C. Phillips High Nucleotide Divergence in Developmental Regulatory Genes Contrasts With the Structural Elements of Olfactory Pathways in Caenorhabditis Genetics, April 1, 2009; 181(4): 1387 - 1397. [Abstract] [Full Text] [PDF]

				E. G. Bakker, M. B. Traw, C. Toomajian, M. Kreitman, and J. Bergelson Low Levels of Polymorphism in Genes That Control the Activation of Defense Response in Arabidopsis thaliana Genetics, April 1, 2008; 178(4): 2031 - 2043. [Abstract] [Full Text] [PDF]

				D. L. Filiault, C. A. Wessinger, J. R. Dinneny, J. Lutes, J. O. Borevitz, D. Weigel, J. Chory, and J. N. Maloof Amino acid polymorphisms in Arabidopsis phytochrome B cause differential responses to light PNAS, February 26, 2008; 105(8): 3157 - 3162. [Abstract] [Full Text] [PDF]

				T. Hernandez-Hernandez, L. P. Martinez-Castilla, and E. R. Alvarez-Buylla Functional Diversification of B MADS-Box Homeotic Regulators of Flower Development: Adaptive Evolution in Protein-Protein Interaction Domains after Major Gene Duplication Events Mol. Biol. Evol., February 1, 2007; 24(2): 465 - 481. [Abstract] [Full Text] [PDF]

				I. Simko, K. G. Haynes, and R. W. Jones Assessment of Linkage Disequilibrium in Potato Genome With Single Nucleotide Polymorphism Markers Genetics, August 1, 2006; 173(4): 2237 - 2245. [Abstract] [Full Text] [PDF]

				S. C. Gonzalez-Martinez, E. Ersoz, G. R. Brown, N. C. Wheeler, and D. B. Neale DNA Sequence Variation and Selection of Tag Single-Nucleotide Polymorphisms at Candidate Genes for Drought-Stress Response in Pinus taeda L. Genetics, March 1, 2006; 172(3): 1915 - 1926. [Abstract] [Full Text] [PDF]

				K. J. Schmid, S. Ramos-Onsins, H. Ringys-Beckstein, B. Weisshaar, and T. Mitchell-Olds A Multilocus Sequence Survey in Arabidopsis thaliana Reveals a Genome-Wide Departure From a Neutral Model of DNA Sequence Polymorphism Genetics, March 1, 2005; 169(3): 1601 - 1615. [Abstract] [Full Text] [PDF]

				R. C. Moore, S. R. Grant, and M. D. Purugganan Molecular Population Genetics of Redundant Floral-Regulatory Genes in Arabidopsis thaliana Mol. Biol. Evol., January 1, 2005; 22(1): 91 - 103. [Abstract] [Full Text] [PDF]

				K. K. Shimizu, J. M. Cork, A. L. Caicedo, C. A. Mays, R. C. Moore, K. M. Olsen, S. Ruzsa, G. Coop, C. D. Bustamante, P. Awadalla, et al. Darwinian Selection on a Selfing Locus Science, December 17, 2004; 306(5704): 2081 - 2084. [Abstract] [Full Text] [PDF]

				A. Palsson, A. Rouse, R. Riley-Berger, I. Dworkin, and G. Gibson Nucleotide Variation in the Egfr Locus of Drosophila melanogaster Genetics, July 1, 2004; 167(3): 1199 - 1212. [Abstract] [Full Text] [PDF]

				E. S. Balakirev and F. J. Ayala Nucleotide Variation in the tinman and bagpipe Homeobox Genes of Drosophila melanogaster Genetics, April 1, 2004; 166(4): 1845 - 1856. [Abstract] [Full Text] [PDF]

				M. J. Clauss and T. Mitchell-Olds Functional Divergence in Tandemly Duplicated Arabidopsis thaliana Trypsin Inhibitor Genes Genetics, March 1, 2004; 166(3): 1419 - 1436. [Abstract] [Full Text] [PDF]

				R. C. Moore and M. D. Purugganan The early stages of duplicate gene evolution PNAS, December 23, 2003; 100(26): 15682 - 15687. [Abstract] [Full Text] [PDF]

				J. Kroymann, S. Donnerhacke, D. Schnabelrauch, and T. Mitchell-Olds Evolutionary dynamics of an Arabidopsis insect resistance quantitative trait locus PNAS, November 25, 2003; 100(suppl_2): 14587 - 14592. [Abstract] [Full Text]

				E. Baudry and F. Depaulis Effect of Misoriented Sites on Neutrality Tests With Outgroup Genetics, November 1, 2003; 165(3): 1619 - 1622. [Abstract] [Full Text] [PDF]

				C. Weinig, L. A. Dorn, N. C. Kane, Z. M. German, S. S. Halldorsdottir, M. C. Ungerer, Y. Toyonaga, T. F. C. Mackay, M. D. Purugganan, and J. Schmitt Heterogeneous Selection at Specific Loci in Natural Environments in Arabidopsis thaliana Genetics, September 1, 2003; 165(1): 321 - 329. [Abstract] [Full Text] [PDF]

				K. A. Shepard and M. D. Purugganan Molecular Population Genetics of the Arabidopsis CLAVATA2 Region: The Genomic Scale of Variation and Selection in a Selfing Species Genetics, March 1, 2003; 163(3): 1083 - 1095. [Abstract] [Full Text] [PDF]

				Y. L. Zhu, Q. J. Song, D. L. Hyten, C. P. Van Tassell, L. K. Matukumalli, D. R. Grimm, S. M. Hyatt, E. W. Fickus, N. D. Young, and P. B. Cregan Single-Nucleotide Polymorphisms in Soybean Genetics, March 1, 2003; 163(3): 1123 - 1134. [Abstract] [Full Text] [PDF]

				M. Barrier, C. D. Bustamante, J. Yu, and M. D. Purugganan Selection on Rapidly Evolving Proteins in the Arabidopsis Genome Genetics, February 1, 2003; 163(2): 723 - 733. [Abstract] [Full Text] [PDF]