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Summary: Gene expression is regulated at multiple levels, including RNA processing and DNA methylation/demethylation. How these regulations are controlled remains unclear.Here, through analysis of a suppressor for the OsEIN2 over‐expressor, we identified an RNA recognition motif protein SUPPRESSOR OF EIN2 (SOE). SOE is localized in nuclear speckles and interacts with several components of the spliceosome. We find SOE associates with hundreds of targets and directly binds to a DNA glycosylase gene DNG701 pre‐mRNA for efficient splicing and stabilization, allowing for subsequent DNG701‐mediated DNA demethylation of the transgene promoter for proper gene expression. The V81M substitution in the suppressor mutant protein mSOE impaired its protein stability and binding activity to DNG701 pre‐mRNA, leading to transgene silencing.SOE mutation enhances grain size and yield. Haplotype analysis in c. 3000 rice accessions reveals that the haplotype 1 (Hap 1) promoter is associated with high 1000‐grain weight, and most of the japonica accessions, but not indica ones, have the Hap 1 elite allele.Our study discovers a novel mechanism for the regulation of gene expression and provides an elite allele for the promotion of yield potentials in rice. See also the Commentary on this article by Bazin & Crespi, 243: 1631–1632. [ABSTRACT FROM AUTHOR]

Rice is an important food crop in the world and the study of its growth and plasticity has a profound influence on sustainable development. Ethylene modulates multiple agronomic traits of rice as well as abiotic and biotic stresses during its lifecycle. It has diverse roles, depending on the organs, developmental stages and environmental conditions. Compared to Arabidopsis (Arabidopsis thaliana), rice ethylene signalling pathway has its own unique features due to its special semiaquatic living environment and distinct plant structure. Ethylene signalling and responses are part of an intricate network in crosstalk with internal and external factors. This review will summarize the current progress in the mechanisms of ethylene‐regulated coleoptile growth in rice, with a special focus on ethylene signaling and interaction with other hormones. Insights into these molecular mechanisms may shed light on ethylene biology and should be beneficial for the genetic improvement of rice and other crops. Summary statement: Ethylene plays essential roles in promoting rice coleoptile elongation under normal and adverse conditions. This review focused on the new roles of ethylene and its interaction with other hormones in promoting rice coleoptile elongation. [ABSTRACT FROM AUTHOR]

Ethylene is a multifunctional hormone involved in regulating plant development, conferring adaptive growth, and responding to biotic/abiotic stresses. Rice is a monocotyledonous crop and usually grows in water environments with some unique features. Here, ethylene biosynthesis, signaling, and interaction with other hormones in rice are summarized and discussed in comparison to those from Arabidopsis and/or other plants. Ethylene biosynthesis in rice responds to internal developmental signals and external stimuli such as grain filling, leaf senescence, darkness, mechanical resistance, hypoxia, chill, salt stress, and metal ions. Gene expression regulation in ethylene biosynthesis pathway shows time and spatial specificity. Through mutant analysis and homologue analysis, an ethylene signaling pathway is proposed in rice, and conserved components/mechanisms as well as new components/mechanisms are identified. Ethylene widely interacts with other hormones in rice by synergy or antagonism. Normally, auxin and gibberellin are synergistic with ethylene to regulate growth, while abscisic acid is antagonistic to ethylene in reproductive growth and various stress response. Ethylene diminishes jasmonic acid–inhibited elongation growth, but synergistically promotes leaf senescence. All these studies provide novel insights into the ethylene biology in rice and other crops, and may facilitate breeding for cultivars with better agronomic traits. [ABSTRACT FROM AUTHOR]

In this study, a full-length cDNA sequence of DREB transcription factor gene, HhDREB2 (GenBank No.: EU872018), was isolated from Halimodendron halodendron. Voss by homology-based cloning and RACE (rapid amplification of cDNA end) technology. Sequence analysis showed that the cDNA sequence was 873 bp without introns and had a maximum open reading frame from 108 to 626 bp, encoding 172 amino acid residues. Molecular weight of the gene encoding protein was 19.702 kDa, isoelectric point was 8.92. Phylogenetic tree and homologous sequence alignment analysis indicated that this protein contained a typical AP2/ERF conservative domain, and was most closely related to soybean GmDREB2, belonging to the A5 subgroups. Yeast one-hybrid experiment demonstrated that HhDREB2 gene encoded a transcription activator. In addition, subcellular localization analysis of a construct with the transient expression vector of the HhDREB2 gene showed that the HhDREB2 protein was localized in the nucleus. The expression level of HhDREB2 gene was greatly induced by high salt, drought and low temperature through semi-quantitative RT-PCR, and had no significant change with GA3, NAA, ABA and 6BA treatments. [ABSTRACT FROM AUTHOR]