Premium
The polycomb group gene EMF 2B is essential for maintenance of floral meristem determinacy in rice
Author(s) -
Conrad Liza J.,
Khanday Imtiyaz,
Johnson Cameron,
Guiderdoni Emmanuel,
An Gynheung,
Vijayraghavan Usha,
Sundaresan Venkatesan
Publication year - 2014
Publication title -
the plant journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.058
H-Index - 269
eISSN - 1365-313X
pISSN - 0960-7412
DOI - 10.1111/tpj.12688
Subject(s) - meristem , gene , determinacy , biology , microbiology and biotechnology , botany , genetics , mathematics , mathematical analysis
Summary Polycomb Repressive Complex 2 ( PRC 2) represses the transcriptional activity of target genes through trimethylation of lysine 27 of histone H3. The functions of plant PRC 2 have been chiefly described in Arabidopsis, but specific functions in other plant species, especially cereals, are still largely unknown. Here we characterize mutants in the rice EMF 2B gene, an ortholog of the Arabidopsis EMBRYONIC FLOWER 2 ( EMF 2 ) gene. Loss of EMF2B in rice results in complete sterility, and mutant flowers have severe floral organ defects and indeterminacy that resemble loss‐of‐function mutants in E‐function floral organ specification genes. Transcriptome analysis identified the E‐function genes Os MADS 1 , Os MADS 6 and Os MADS 34 as differentially expressed in the emf2b mutant compared with wild type. Os MADS 1 and Os MADS 6 , known to be required for meristem determinacy in rice, have reduced expression in the emf2b mutant, whereas Os MADS 34 which interacts genetically with Os MADS 1 was ectopically expressed. Chromatin immunoprecipitation for H3K27me3 followed by quantitative (q) RT ‐ PCR showed that all three genes are presumptive targets of PRC 2 in the meristem. Therefore, in rice, and possibly other cereals, PRC 2 appears to play a major role in floral meristem determinacy through modulation of the expression of E‐function genes.