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Title: A methyltransferase required for proper timing of the vernalization response in Arabidopsis

Abstract

Prolonged exposure to winter cold enables flowering in many plant species through a process called vernalization. In Arabidopsis, vernalization results from the epigenetic silencing of the floral repressor FLOWERING LOCUS C (FLC) via a Polycomb Repressive Complex 2 (PRC2)-mediated increase in the density of the epigenetic silencing mark H3K27me3 at FLC chromatin. During cold exposure, a gene encoding a unique, cold-specific PRC2 component, VERNALIZATION INSENSITIVE 3 (VIN3), which is necessary for PRC2-mediated silencing of FLC, is induced. In this paper, we show that SET DOMAIN GROUP 7 (SDG7) is required for proper timing of VIN3 induction and of the vernalization process. Loss of SDG7 results in a vernalization-hypersensitive phenotype, as well as more rapid cold-mediated up-regulation of VIN3. In the absence of cold, loss of SDG7 results in elevated levels of long noncoding RNAs, which are thought to participate in epigenetic repression of FLC. Furthermore, loss of SDG7 results in increased H3K27me3 deposition on FLC chromatin in the absence of cold exposure and enhanced H3K27me3 spreading during cold treatment. In conclusion, SDG7 is a negative regulator of vernalization, and loss of SDG7 creates a partially vernalized state without cold exposure.

Authors:
 [1];  [1];  [2];  [2];  [1]
  1. Univ. of Wisconsin, Madison, WI (United States)
  2. Centre National de la Recherche Scientifique (CNRS), Strasbourg (France)
Publication Date:
Research Org.:
Univ. of Wisconsin, Madison, WI (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
OSTI Identifier:
1349032
Grant/Contract Number:
FC02-07ER64494
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Proceedings of the National Academy of Sciences of the United States of America
Additional Journal Information:
Journal Volume: 112; Journal Issue: 7; Journal ID: ISSN 0027-8424
Publisher:
National Academy of Sciences, Washington, DC (United States)
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; vernalization; flowering time; SET DOMAIN GROUP 7

Citation Formats

Lee, Joohyun, Yun, Jae-Young, Zhao, Wei, Shen, Wen-Hui, and Amasino, Richard M. A methyltransferase required for proper timing of the vernalization response in Arabidopsis. United States: N. p., 2015. Web. doi:10.1073/pnas.1423585112.
Lee, Joohyun, Yun, Jae-Young, Zhao, Wei, Shen, Wen-Hui, & Amasino, Richard M. A methyltransferase required for proper timing of the vernalization response in Arabidopsis. United States. doi:10.1073/pnas.1423585112.
Lee, Joohyun, Yun, Jae-Young, Zhao, Wei, Shen, Wen-Hui, and Amasino, Richard M. Tue . "A methyltransferase required for proper timing of the vernalization response in Arabidopsis". United States. doi:10.1073/pnas.1423585112. https://www.osti.gov/servlets/purl/1349032.
@article{osti_1349032,
title = {A methyltransferase required for proper timing of the vernalization response in Arabidopsis},
author = {Lee, Joohyun and Yun, Jae-Young and Zhao, Wei and Shen, Wen-Hui and Amasino, Richard M.},
abstractNote = {Prolonged exposure to winter cold enables flowering in many plant species through a process called vernalization. In Arabidopsis, vernalization results from the epigenetic silencing of the floral repressor FLOWERING LOCUS C (FLC) via a Polycomb Repressive Complex 2 (PRC2)-mediated increase in the density of the epigenetic silencing mark H3K27me3 at FLC chromatin. During cold exposure, a gene encoding a unique, cold-specific PRC2 component, VERNALIZATION INSENSITIVE 3 (VIN3), which is necessary for PRC2-mediated silencing of FLC, is induced. In this paper, we show that SET DOMAIN GROUP 7 (SDG7) is required for proper timing of VIN3 induction and of the vernalization process. Loss of SDG7 results in a vernalization-hypersensitive phenotype, as well as more rapid cold-mediated up-regulation of VIN3. In the absence of cold, loss of SDG7 results in elevated levels of long noncoding RNAs, which are thought to participate in epigenetic repression of FLC. Furthermore, loss of SDG7 results in increased H3K27me3 deposition on FLC chromatin in the absence of cold exposure and enhanced H3K27me3 spreading during cold treatment. In conclusion, SDG7 is a negative regulator of vernalization, and loss of SDG7 creates a partially vernalized state without cold exposure.},
doi = {10.1073/pnas.1423585112},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
number = 7,
volume = 112,
place = {United States},
year = {Tue Jan 20 00:00:00 EST 2015},
month = {Tue Jan 20 00:00:00 EST 2015}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 8works
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