A histone methyltransferase inhibits seed germination by increasing PIF1 mRNA expression in imbibed seeds. (26th March 2014)

• Record Type: Journal Article
• Authors: Lee, Nayoung; Kang, Hyojin; Lee, Daeyoup; Choi, Giltsu
• Is Part Of: Plant journal. Volume 78:Number 2(2014:Apr.)
• Page Start: 282
• Page End: 293
• Publication Date: 2014-03-26
• Subjects: Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.12467
• Languages: English
• ISSNs: 0960-7412

Abstract

<abstract abstract-type="main" id="tpj12467-abs-0001"> <title>Summary</title> <p>Phytochrome‐interacting factor 1 (PIF1) inhibits light‐dependent seed germination. The specific function of PIF1 in seed germination is partly due to its high level of expression in imbibed seeds, but the associated regulatory factors have not been identified. Here we show that mutation of the <italic>early flowering in short days (EFS)</italic> gene, encoding an H3K4 and H3K36 methyltransferase, decreases the level of H3K36me2 and H3K36me3 but not H3K4me3 at the <italic>PIF1</italic> locus, reduces the targeting of RNA polymerase II to the <italic>PIF1</italic> locus, and reduces mRNA expression of <italic>PIF1</italic> in imbibed seeds. Consistently, the <italic>efs</italic> mutant geminated even under the phyB<sub>off</sub> condition, and had an expression profile of PIF1 target genes similar to that of the <italic>pif1</italic> mutant. Introduction of an <italic>EFS</italic> transgene into the <italic>efs</italic> mutant restored the level of H3K36me2 and H3K36me3 at the <italic>PIF1</italic> locus, the high‐level expression of <italic>PIF1</italic> mRNA, the expression pattern of PIF1 target genes, and the light‐dependent germination of these seeds. Introduction of a <italic>PIF1</italic> transgene into the <italic>efs</italic> mutant also restored the expression pattern of PIF1 target genes and light‐dependent germination in imbibed seeds, but did not restore the flowering phenotype. Taken together, our results indicate that EFS is necessary for high‐level expression of <italic>PIF1</italic> mRNA in imbibed seeds.</p> </abstract>