Control of PHERES1 imprinting in Arabidopsis by direct tandem repeats.
Genomic imprinting is an epigenetic phenomenon that causes monoallelic expression of specific genes dependent on the parent-of-origin. Imprinting of the Arabidopsis gene PHERES1 requires the function of the FERTILIZATION INDEPENDENT SEED (FIS) Polycomb group complex as well as a distally located methylated region containing a tandem triple repeat sequence. In this study, we investigated the regulation of the close PHERES1 homolog PHERES2. We found that PHERES2 is also a direct target gene of the FIS Polycomb group complex, but, in contrast to PHERES1, PHERES2 is equally expressed from maternal and paternal alleles. Thus, PHERES2 is not regulated by genomic imprinting, correlating with the lack of tandem repeats at PHERES2. Eliminating tandem repeats from the PHERES1 locus abolishes PHERES1 imprinting, demonstrating that tandem repeats are essential for PHERES1 imprinting. Taking these results together, our study shows that the recently duplicated genes PHERES1 and PHERES2 are both target genes of the FIS Polycomb group complex but only PHERES1 is regulated by genomic imprinting, which is likely caused by the presence of repeat sequences in the proximity of the PHERES1 locus.
Villar
Corina Belle R
CBR
Department of Biology and Zurich-Basel Plant Science Center, Swiss Federal Institute of Technology, ETH Centre, CH-8092 Zurich, Switzerland.
Erilova
Aleksandra
A
Department of Biology and Zurich-Basel Plant Science Center, Swiss Federal Institute of Technology, ETH Centre, CH-8092 Zurich, Switzerland.
Makarevich
Grigory
G
Department of Biology and Zurich-Basel Plant Science Center, Swiss Federal Institute of Technology, ETH Centre, CH-8092 Zurich, Switzerland.
Trösch
Raphael
R
Department of Biology and Zurich-Basel Plant Science Center, Swiss Federal Institute of Technology, ETH Centre, CH-8092 Zurich, Switzerland.
Köhler
Claudia
C
Department of Biology and Zurich-Basel Plant Science Center, Swiss Federal Institute of Technology, ETH Centre, CH-8092 Zurich, Switzerland. Electronic address: koehlerc@ethz.ch.
D000483:Alleles; D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics*; D042002:Chromatin Assembly and Disassembly / Q000235:genetics; D047369:Chromatin Immunoprecipitation; D044127:Epigenesis, Genetic / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D018392:Genomic Imprinting / Q000235:genetics*; D026161:MADS Domain Proteins / Q000235:genetics*; D030821:Plants, Genetically Modified / Q000235:genetics*; D016133:Polymerase Chain Reaction; D020080:Tandem Repeat Sequences / Q000235:genetics*
D029681:Arabidopsis Proteins; D026161:MADS Domain Proteins; C475745:PHERES1 protein, Arabidopsis