Arabidopsis MET1 Cytosine Methyltransferase Mutants

Corresponding author: Eric J. Richards, Washington University, Campus Box 1137, 1 Brookings Dr., St. Louis, MO 63130., richards{at}biology.wustl.edu (E-mail)

Communicating editor: S. HENIKOFF

We describe the isolation and characterization of two missense mutations in the cytosine-DNA-methyltransferase gene, MET1, from the flowering plant Arabidopsis thaliana. Both missense mutations, which affect the catalytic domain of the protein, led to a global reduction of cytosine methylation throughout the genome. Surprisingly, the met1-2 allele, with the weaker DNA hypomethylation phenotype, alters a well-conserved residue in methyltransferase signature motif I. The stronger met1-1 allele caused late flowering and a heterochronic delay in the juvenile-to-adult rosette leaf transition. The distribution of late-flowering phenotypes in a mapping population segregating met1-1 indicates that the flowering-time phenotype is caused by the accumulation of inherited defects at loci unlinked to the met1 mutation. The delay in flowering time is due in part to the formation and inheritance of hypomethylated fwa epialleles, but inherited defects at other loci are likely to contribute as well. Centromeric repeat arrays hypomethylated in met1-1 mutants are partially remethylated when introduced into a wild-type background, in contrast to genomic sequences hypomethylated in ddm1 mutants. ddm1 met1 double mutants were constructed to further our understanding of the mechanism of DDM1 action and the interaction between two major genetic loci affecting global cytosine methylation levels in Arabidopsis.

This article has been cited by other articles:

				R. Lister and J. R. Ecker Finding the fifth base: Genome-wide sequencing of cytosine methylation Genome Res., June 1, 2009; 19(6): 959 - 966. [Abstract] [Full Text] [PDF]

				R. Ishikawa and T. Kinoshita Epigenetic Programming: The Challenge to Species Hybridization Mol Plant, May 14, 2009; (2009) ssp028v1. [Abstract] [Full Text] [PDF]

				J. Reinders, B. B.H. Wulff, M. Mirouze, A. Mari-Ordonez, M. Dapp, W. Rozhon, E. Bucher, G. Theiler, and J. Paszkowski Compromised stability of DNA methylation and transposon immobilization in mosaic Arabidopsis epigenomes Genes & Dev., April 15, 2009; 23(8): 939 - 950. [Abstract] [Full Text] [PDF]

				F. K. Teixeira, F. Heredia, A. Sarazin, F. Roudier, M. Boccara, C. Ciaudo, C. Cruaud, J. Poulain, M. Berdasco, M. F. Fraga, et al. A Role for RNAi in the Selective Correction of DNA Methylation Defects Science, March 20, 2009; 323(5921): 1600 - 1604. [Abstract] [Full Text] [PDF]

				S. Tiwari, R. Schulz, Y. Ikeda, L. Dytham, J. Bravo, L. Mathers, M. Spielman, P. Guzman, R. J. Oakey, T. Kinoshita, et al. MATERNALLY EXPRESSED PAB C-TERMINAL, a Novel Imprinted Gene in Arabidopsis, Encodes the Conserved C-Terminal Domain of Polyadenylate Binding Proteins PLANT CELL, September 1, 2008; 20(9): 2387 - 2398. [Abstract] [Full Text] [PDF]

				R. J. Scott, S. J. Armstrong, J. Doughty, and M. Spielman Double Fertilization in Arabidopsis thaliana Involves a Polyspermy Block on the Egg but Not the Central Cell Mol Plant, July 1, 2008; 1(4): 611 - 619. [Abstract] [Full Text] [PDF]

				J. Perez-Hormaeche, F. Potet, L. Beauclair, I. Le Masson, B. Courtial, N. Bouche, and H. Lucas Invasion of the Arabidopsis Genome by the Tobacco Retrotransposon Tnt1 Is Controlled by Reversible Transcriptional Gene Silencing Plant Physiology, July 1, 2008; 147(3): 1264 - 1278. [Abstract] [Full Text] [PDF]

				I. R. Henderson and S. E. Jacobsen Tandem repeats upstream of the Arabidopsis endogene SDC recruit non-CG DNA methylation and initiate siRNA spreading Genes & Dev., June 15, 2008; 22(12): 1597 - 1606. [Abstract] [Full Text] [PDF]

				M. Chen, M. Ha, E. Lackey, J. Wang, and Z. J. Chen RNAi of met1 Reduces DNA Methylation and Induces Genome-Specific Changes in Gene Expression and Centromeric Small RNA Accumulation in Arabidopsis Allopolyploids Genetics, April 1, 2008; 178(4): 1845 - 1858. [Abstract] [Full Text] [PDF]

				G. Makarevich, C. B. R. Villar, A. Erilova, and C. Kohler Mechanism of PHERES1 imprinting in Arabidopsis J. Cell Sci., March 15, 2008; 121(6): 906 - 912. [Abstract] [Full Text] [PDF]

				H. Saze, A. Shiraishi, A. Miura, and T. Kakutani Control of Genic DNA Methylation by a jmjC Domain-Containing Protein in Arabidopsis thaliana Science, January 25, 2008; 319(5862): 462 - 465. [Abstract] [Full Text] [PDF]

				I. Makarevitch, R. M. Stupar, A. L. Iniguez, W. J. Haun, W. B. Barbazuk, S. M. Kaeppler, and N. M. Springer Natural Variation for Alleles Under Epigenetic Control by the Maize Chromomethylase Zmet2 Genetics, October 1, 2007; 177(2): 749 - 760. [Abstract] [Full Text] [PDF]

				S. H. Rangwala and E. J. Richards Differential Epigenetic Regulation Within an Arabidopsis Retroposon Family Genetics, May 1, 2007; 176(1): 151 - 160. [Abstract] [Full Text] [PDF]

				H. R. Woo, O. Pontes, C. S. Pikaard, and E. J. Richards VIM1, a methylcytosine-binding protein required for centromeric heterochromatinization Genes & Dev., February 1, 2007; 21(3): 267 - 277. [Abstract] [Full Text] [PDF]

				Y. Ikeda, Y. Kobayashi, A. Yamaguchi, M. Abe, and T. Araki Molecular Basis of Late-Flowering Phenotype Caused by Dominant Epi-Alleles of the FWA Locus in Arabidopsis Plant Cell Physiol., February 1, 2007; 48(2): 205 - 220. [Abstract] [Full Text] [PDF]

				L. Mull, M. L. Ebbs, and J. Bender A Histone Methylation-Dependent DNA Methylation Pathway Is Uniquely Impaired by Deficiency in Arabidopsis S-Adenosylhomocysteine Hydrolase Genetics, November 1, 2006; 174(3): 1161 - 1171. [Abstract] [Full Text] [PDF]

				W. Xiao, R. C. Brown, B. E. Lemmon, J. J. Harada, R. B. Goldberg, and R. L. Fischer Regulation of Seed Size by Hypomethylation of Maternal and Paternal Genomes Plant Physiology, November 1, 2006; 142(3): 1160 - 1168. [Abstract] [Full Text] [PDF]

				H. Shaked, N. Avivi-Ragolsky, and A. A. Levy Involvement of the Arabidopsis SWI2/SNF2 Chromatin Remodeling Gene Family in DNA Damage Response and Recombination Genetics, June 1, 2006; 173(2): 985 - 994. [Abstract] [Full Text] [PDF]

				R. Bouveret, N. Schonrock, W. Gruissem, and L. Hennig Regulation of flowering time by Arabidopsis MSI1 Development, May 1, 2006; 133(9): 1693 - 1702. [Abstract] [Full Text] [PDF]

				W. Xiao, K. D. Custard, R. C. Brown, B. E. Lemmon, J. J. Harada, R. B. Goldberg, and R. L. Fischer DNA Methylation Is Critical for Arabidopsis Embryogenesis and Seed Viability PLANT CELL, April 1, 2006; 18(4): 805 - 814. [Abstract] [Full Text] [PDF]

				X. ZHANG and S.E. JACOBSEN Genetic Analyses of DNA Methyltransferases in Arabidopsis thaliana Cold Spring Harb Symp Quant Biol, January 1, 2006; 71(0): 439 - 447. [Abstract] [PDF]

				M. R. Woodhouse, M. Freeling, and D. Lisch The mop1 (mediator of paramutation1) Mutant Progressively Reactivates One of the Two Genes Encoded by the MuDR Transposon in Maize Genetics, January 1, 2006; 172(1): 579 - 592. [Abstract] [Full Text] [PDF]

				A. Zemach, Y. Li, H. Ben-Meir, M. Oliva, A. Mosquna, V. Kiss, Y. Avivi, N. Ohad, and G. Grafi Different Domains Control the Localization and Mobility of LIKE HETEROCHROMATIN PROTEIN1 in Arabidopsis Nuclei PLANT CELL, January 1, 2006; 18(1): 133 - 145. [Abstract] [Full Text] [PDF]

				M. L. Ebbs, L. Bartee, and J. Bender H3 Lysine 9 Methylation Is Maintained on a Transcribed Inverted Repeat by Combined Action of SUVH6 and SUVH4 Methyltransferases Mol. Cell. Biol., December 1, 2005; 25(23): 10507 - 10515. [Abstract] [Full Text] [PDF]

				A. Zemach, Y. Li, B. Wayburn, H. Ben-Meir, V. Kiss, Y. Avivi, V. Kalchenko, S. E. Jacobsen, and G. Grafi DDM1 Binds Arabidopsis Methyl-CpG Binding Domain Proteins and Affects Their Subnuclear Localization PLANT CELL, May 1, 2005; 17(5): 1549 - 1558. [Abstract] [Full Text] [PDF]

				G. Yang, Y.-H. Lee, Y. Jiang, X. Shi, S. Kertbundit, and T. C. Hall A Two-Edged Role for the Transposable Element Kiddo in the rice ubiquitin2 Promoter PLANT CELL, May 1, 2005; 17(5): 1559 - 1568. [Abstract] [Full Text] [PDF]

				S. Chang and C. S. Pikaard Transcript Profiling in Arabidopsis Reveals Complex Responses to Global Inhibition of DNA Methylation and Histone Deacetylation J. Biol. Chem., January 7, 2005; 280(1): 796 - 804. [Abstract] [Full Text] [PDF]

				O. Mathieu and J. Bender RNA-directed DNA methylation J. Cell Sci., October 1, 2004; 117(21): 4881 - 4888. [Abstract] [Full Text] [PDF]

				M. Kato, K. Takashima, and T. Kakutani Epigenetic Control of CACTA Transposon Mobility in Arabidopsis thaliana Genetics, October 1, 2004; 168(2): 961 - 969. [Abstract] [Full Text] [PDF]

				A. MADLUNG and L. COMAI The Effect of Stress on Genome Regulation and Structure Ann. Bot., October 1, 2004; 94(4): 481 - 495. [Abstract] [Full Text] [PDF]

				M. Gehring, Y. Choi, and R. L. Fischer Imprinting and Seed Development PLANT CELL, June 1, 2004; 16(suppl_1): S203 - S213. [Full Text] [PDF]

				S. Takeda, Z. Tadele, I. Hofmann, A. V. Probst, K. J. Angelis, H. Kaya, T. Araki, T. Mengiste, O. M. Scheid, K.-i. Shibahara, et al. BRU1, a novel link between responses to DNA damage and epigenetic gene silencing in Arabidopsis Genes & Dev., April 1, 2004; 18(7): 782 - 793. [Abstract] [Full Text] [PDF]

				T. Kinoshita, A. Miura, Y. Choi, Y. Kinoshita, X. Cao, S. E. Jacobsen, R. L. Fischer, and T. Kakutani One-Way Control of FWA Imprinting in Arabidopsis Endosperm by DNA Methylation Science, January 23, 2004; 303(5657): 521 - 523. [Abstract] [Full Text] [PDF]

				T. KAKUTANI, M. KATO, T. KINOSHITA, and A. MIURA Control of Development and Transposon Movement by DNA Methylation in Arabidopsis thaliana Cold Spring Harb Symp Quant Biol, January 1, 2004; 69(0): 139 - 144. [Abstract] [PDF]

				J. BENDER DNA Methylation of the Endogenous PAI Genes in Arabidopsis Cold Spring Harb Symp Quant Biol, January 1, 2004; 69(0): 145 - 154. [Abstract] [PDF]

				H. YI, N.C. RIDDLE, T.L. STOKES, H.-R. WOO, and E.J. RICHARDS Induced and Natural Epigenetic Variation Cold Spring Harb Symp Quant Biol, January 1, 2004; 69(0): 155 - 160. [Abstract] [PDF]

				M. Tariq, H. Saze, A. V. Probst, J. Lichota, Y. Habu, and J. Paszkowski Erasure of CpG methylation in Arabidopsis alters patterns of histone H3 methylation in heterochromatin PNAS, July 22, 2003; 100(15): 8823 - 8827. [Abstract] [Full Text] [PDF]