Title: Establishment of a vernalization requirement in Brachypodium distachyon requires REPRESSOR OF VERNALIZATION1

Abstract

A requirement for vernalization, the process by which prolonged cold exposure provides competence to flower, is an important adaptation to temperate climates that ensures flowering does not occur before the onset of winter. In temperate grasses, vernalization results in the up-regulation of VERNALIZATION1 (VRN1) to establish competence to flower; however, little is known about the mechanism underlying repression of VRN1 in the fall season, which is necessary to establish a vernalization requirement. In this paper, we report that a plant-specific gene containing a bromo-adjacent homology and transcriptional elongation factor S-II domain, which we named REPRESSOR OF VERNALIZATION1 (RVR1), represses VRN1 before vernalization in Brachypodium distachyon. That RVR1 is upstream of VRN1 is supported by the observations that VRN1 is precociously elevated in an rvr1 mutant, resulting in rapid flowering without cold exposure, and the rapid-flowering rvr1 phenotype is dependent on VRN1. The precocious VRN1 expression in rvr1 is associated with reduced levels of the repressive chromatin modification H3K27me3 at VRN1, which is similar to the reduced VRN1 H3K27me3 in vernalized plants. Furthermore, the transcriptome of vernalized wild-type plants overlaps with that of nonvernalized rvr1 plants, indicating loss of rvr1 is similar to the vernalized state at a molecular level. However,more » loss of rvr1 results in more differentially expressed genes than does vernalization, indicating that RVR1 may be involved in processes other than vernalization despite a lack of any obvious pleiotropy in the rvr1 mutant. This study provides an example of a role for this class of plant-specific genes.« less

Authors:

Woods, Daniel P. ;

• Search DOE PAGES for author "Woods, Daniel P."
• Search DOE PAGES for ORCID "0000-0002-1498-5707"

Ream, Thomas S.; Bouché, Frédéric ;

• Search DOE PAGES for author "Bouché, Frédéric"
• Search DOE PAGES for ORCID "0000-0002-8017-0071"

Lee, Joohyun; Thrower, Nicholas; Wilkerson, Curtis; Amasino, Richard M.

• Search DOE PAGES for author "Amasino, Richard M."
• Search DOE PAGES for ORCID "0000-0003-3068-5402"

Publication Date:

Mon Jun 05 00:00:00 EDT 2017

Research Org.:

Univ. of Wisconsin, Madison, WI (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Biological and Environmental Research (BER)

OSTI Identifier:

1361438

Alternate Identifier(s):

OSTI ID: 1532918

Grant/Contract Number:  

FCO2-07ER64494; FC02-07ER64494

Resource Type:

Published Article

Journal Name:

Proceedings of the National Academy of Sciences of the United States of America

Additional Journal Information:

Journal Name: Proceedings of the National Academy of Sciences of the United States of America; 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; science & technology; vernalization; Brachypodium; flowering; VRN1; RVR1