日
 Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The . gov means it’s official. Federal government websites often end in . gov or . mil. Before sharing sensitive information, make sure you’re on a federal government site. VSports app下载.

Https

The site is secure. The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely V体育官网. .

. 2009 Jun 12;324(5933):1447-51.
doi: 10.1126/science.1171609.

Extensive demethylation of repetitive elements during seed development underlies gene imprinting (V体育安卓版)

Mary Gehring  1 , Kerry L Bubb, Steven Henikoff
Affiliations

Extensive demethylation of repetitive elements during seed development underlies gene imprinting

Mary Gehring et al. Science. .

Abstract

DNA methylation is an epigenetic mark associated with transposable element silencing and gene imprinting in flowering plants and mammals. In plants, imprinting occurs in the endosperm, which nourishes the embryo during seed development. We have profiled Arabidopsis DNA methylation genome-wide in the embryo and endosperm and found that large-scale methylation changes accompany endosperm development and endosperm-specific gene expression. Transposable element fragments are extensively demethylated in the endosperm. We discovered new imprinted genes by the identification of candidates associated with regions of reduced endosperm methylation and preferential expression in endosperm relative to other parts of the plant VSports手机版. These data suggest that imprinting in plants evolved from targeted methylation of transposable element insertions near genic regulatory elements followed by positive selection when the resulting expression change was advantageous. .

PubMed Disclaimer

Figures

Figure 1
Figure 1. Endosperm is less methylated than embryo
A) Typical methylation profiles from a gene-rich and gene-poor region of the genome showing highly similar methylation patterns in embryo, endosperm, and dme endosperm from the Ler and Col-gl accessions. B) Average methylation in 100-bp windows of protein-coding genes and transposable element genes aligned at either their 5′ or 3′ ends in Col-gl embryo and endosperm. C) Methylation profiles of protein-coding genes when a set of 31,076 transposable element fragments (11) are and are not excluded from the averaging.
Figure 2
Figure 2. Known imprinted genes are associated with top DMRs
A) Histogram of Col-gl embryo - endosperm difference scores for 1.2 million overlapping 300-bp segments. Dashed lines represent the cutoff for the top 0.5% of methylation differences (~6000 300-bp segments). B) Embryo and endosperm methylation profiles of known imprinted genes. Red arrows, regions within the top 0.5% of methylation differences; gray arrow, region below the cutoff.
Figure 3
Figure 3. Methylation is lost 5′ and 3′ of genes in the endosperm
Average methylation profiles in embryo, endosperm, and dme endosperm of the A) 1276 Col-gl and B) 1163 Ler genes associated with more methylation in embryo than endosperm. Genes were aligned at their 5′ or 3′ end and the average methylation determined every 100 bp.
Figure 4
Figure 4. Expression and methylation analysis of new imprinted genes
A) RT-PCR allele-specific expression analysis from endosperm RNA of Col-gl females X Ler males and Ler females X Col-gl males. FWA is a control imprinted gene; AT3G25260 is biallelic. B) RT-PCR sequencing chromatograms for the paternally expressed genes AT2G32370 and AT5G62110. The biallelically-expressed gene αVPE is shown as a control. C) and D) Methylation profiling and allele-specific bisulfite sequencing analysis of new imprinted genes. Dashed lines represent the cutoff for the top 0.5% of differences. Each line of circles represent a bisulfite sequencing clone from embryo or endosperm. Filled circle, methylated cytosine. Red, CG; blue, CHG; gray, CHH.
See this image and copyright information in PMC

References

    1. Huh JH, Bauer MJ, Hsieh TF, Fischer RL. Cell. 2008;132:735. - PubMed
    1. Gutierrez-Marcos JF, et al. Nat Genet. 2006;38:876. - PubMed
    1. Zilberman D, Gehring M, Tran RK, Ballinger T, Henikoff S. Nat Genet. 2007;39:61. - "VSports app下载" PubMed
    1. Zhang X, et al. Cell. 2006;126:1189. - PubMed (VSports在线直播)
    1. Lauria M, et al. Plant Cell. 2004;16:510. - PMC - PubMed

VSports在线直播 - Publication types

MeSH terms

Associated data