Hypomethylation and hypermethylation of the tandem repetitive 5S rRNA genes in Arabidopsis.

Isabelle Vaillant; Sylvie Tutois; Zusana Jasencakova; Julien Douet; Ingo Schubert; Sylvette Tourmente

doi:10.1111/j.1365-313X.2008.03413.x

Hypomethylation and hypermethylation of the tandem repetitive 5S rRNA genes in Arabidopsis.

Isabelle Vaillant, Sylvie Tutois, Zusana Jasencakova, Julien Douet, Ingo Schubert, Sylvette Tourmente

Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › peer review

15 Citationer (Scopus)

Abstract

Udgivelsesdato: 2008-Apr

Originalsprog	Engelsk
Tidsskrift	Plant Journal
Vol/bind	54
Udgave nummer	2
Sider (fra-til)	299-309
Antal sider	10
ISSN	0960-7412
DOI	https://doi.org/10.1111/j.1365-313X.2008.03413.x
Status	Udgivet - 2008
Udgivet eksternt	Ja

Bibliografisk note

Keywords: Arabidopsis; Arabidopsis Proteins; DNA Methylation; DNA, Ribosomal; Gene Expression Regulation, Plant; Gene Silencing; Genes, Plant; RNA, Ribosomal, 5S; Tandem Repeat Sequences; Time Factors

Adgang til dokumentet

10.1111/j.1365-313X.2008.03413.x

Citationsformater

@article{0ad81420518b11dd8d9f000ea68e967b,

title = "Hypomethylation and hypermethylation of the tandem repetitive 5S rRNA genes in Arabidopsis.",

abstract = "5S ribosomal DNA (5S rDNA) is organized in tandem repeats on chromosomes 3, 4 and 5 in Arabidopsis thaliana. One part of the 5S rDNA is located within the heterochromatic chromocenters, and the other fraction forms loops with euchromatic features that emanate from the chromocenters. We investigated whether the A. thaliana heterochromatin, and particularly the 5S rDNA, is modified when changing the culture conditions (cultivation in growth chamber versus greenhouse). Nuclei from challenged tissues displayed larger total, as well as 5S rDNA, heterochromatic fractions, and the DNA methyltransferase mutants met1 and cmt3 had different impacts in Arabidopsis. The enlarged fraction of heterochromatic 5S rDNA was observed, together with the reversal of the silencing of some 5S rRNA genes known as minor genes. We observed hypermethylation at CATG sites, and a concomitant DNA hypomethylation at CG/CXG sites in 5S rDNA. Our results show that the asymmetrical hypermethylation is correlated with the ageing of the plants, whereas hypomethylation results from the growth chamber/culture conditions. In spite of severely reduced DNA methylation, the met1 mutant revealed no increase in minor 5S rRNA transcripts in these conditions. The increasing proportion of cytosines in asymmetrical contexts during transition from the euchromatic to the heterochromatic state in the 5S rDNA array suggests that 5S rDNA units are differently affected by the (hypo and hyper)methylation patterns along the 5S rDNA locus. This might explain the different behaviour of 5S rDNA subpopulations inside a 5S array in terms of chromatin compaction and expression, i.e. some 5S rRNA genes would become derepressed, whereas others would join the heterochromatic fraction.",

author = "Isabelle Vaillant and Sylvie Tutois and Zusana Jasencakova and Julien Douet and Ingo Schubert and Sylvette Tourmente",

note = "Keywords: Arabidopsis; Arabidopsis Proteins; DNA Methylation; DNA, Ribosomal; Gene Expression Regulation, Plant; Gene Silencing; Genes, Plant; RNA, Ribosomal, 5S; Tandem Repeat Sequences; Time Factors",

year = "2008",

doi = "10.1111/j.1365-313X.2008.03413.x",

language = "English",

volume = "54",

pages = "299--309",

journal = "Plant Journal",

issn = "0960-7412",

publisher = "Wiley-Blackwell",

number = "2",

}

TY - JOUR

T1 - Hypomethylation and hypermethylation of the tandem repetitive 5S rRNA genes in Arabidopsis.

AU - Vaillant, Isabelle

AU - Tutois, Sylvie

AU - Jasencakova, Zusana

AU - Douet, Julien

AU - Schubert, Ingo

AU - Tourmente, Sylvette

N1 - Keywords: Arabidopsis; Arabidopsis Proteins; DNA Methylation; DNA, Ribosomal; Gene Expression Regulation, Plant; Gene Silencing; Genes, Plant; RNA, Ribosomal, 5S; Tandem Repeat Sequences; Time Factors

PY - 2008

Y1 - 2008

N2 - 5S ribosomal DNA (5S rDNA) is organized in tandem repeats on chromosomes 3, 4 and 5 in Arabidopsis thaliana. One part of the 5S rDNA is located within the heterochromatic chromocenters, and the other fraction forms loops with euchromatic features that emanate from the chromocenters. We investigated whether the A. thaliana heterochromatin, and particularly the 5S rDNA, is modified when changing the culture conditions (cultivation in growth chamber versus greenhouse). Nuclei from challenged tissues displayed larger total, as well as 5S rDNA, heterochromatic fractions, and the DNA methyltransferase mutants met1 and cmt3 had different impacts in Arabidopsis. The enlarged fraction of heterochromatic 5S rDNA was observed, together with the reversal of the silencing of some 5S rRNA genes known as minor genes. We observed hypermethylation at CATG sites, and a concomitant DNA hypomethylation at CG/CXG sites in 5S rDNA. Our results show that the asymmetrical hypermethylation is correlated with the ageing of the plants, whereas hypomethylation results from the growth chamber/culture conditions. In spite of severely reduced DNA methylation, the met1 mutant revealed no increase in minor 5S rRNA transcripts in these conditions. The increasing proportion of cytosines in asymmetrical contexts during transition from the euchromatic to the heterochromatic state in the 5S rDNA array suggests that 5S rDNA units are differently affected by the (hypo and hyper)methylation patterns along the 5S rDNA locus. This might explain the different behaviour of 5S rDNA subpopulations inside a 5S array in terms of chromatin compaction and expression, i.e. some 5S rRNA genes would become derepressed, whereas others would join the heterochromatic fraction.

AB - 5S ribosomal DNA (5S rDNA) is organized in tandem repeats on chromosomes 3, 4 and 5 in Arabidopsis thaliana. One part of the 5S rDNA is located within the heterochromatic chromocenters, and the other fraction forms loops with euchromatic features that emanate from the chromocenters. We investigated whether the A. thaliana heterochromatin, and particularly the 5S rDNA, is modified when changing the culture conditions (cultivation in growth chamber versus greenhouse). Nuclei from challenged tissues displayed larger total, as well as 5S rDNA, heterochromatic fractions, and the DNA methyltransferase mutants met1 and cmt3 had different impacts in Arabidopsis. The enlarged fraction of heterochromatic 5S rDNA was observed, together with the reversal of the silencing of some 5S rRNA genes known as minor genes. We observed hypermethylation at CATG sites, and a concomitant DNA hypomethylation at CG/CXG sites in 5S rDNA. Our results show that the asymmetrical hypermethylation is correlated with the ageing of the plants, whereas hypomethylation results from the growth chamber/culture conditions. In spite of severely reduced DNA methylation, the met1 mutant revealed no increase in minor 5S rRNA transcripts in these conditions. The increasing proportion of cytosines in asymmetrical contexts during transition from the euchromatic to the heterochromatic state in the 5S rDNA array suggests that 5S rDNA units are differently affected by the (hypo and hyper)methylation patterns along the 5S rDNA locus. This might explain the different behaviour of 5S rDNA subpopulations inside a 5S array in terms of chromatin compaction and expression, i.e. some 5S rRNA genes would become derepressed, whereas others would join the heterochromatic fraction.

U2 - 10.1111/j.1365-313X.2008.03413.x

DO - 10.1111/j.1365-313X.2008.03413.x

M3 - Journal article

C2 - 18208523

SN - 0960-7412

VL - 54

SP - 299

EP - 309

JO - Plant Journal

JF - Plant Journal

IS - 2

ER -