Involvement of Histone Modifications in Plant Abiotic Stress Responses

As sessile organisms, plants encounter various environmental stimuli including abiotic stresses during their lifecycle. To survive under adverse conditions, plants have evolved intricate mechanisms to ...     

光调控植物种子萌发分子机制研究进展

萌发是种子植物进入农业生态系统的重要发育阶段。对于需光类种子,光是调控其萌发最重要的环境信号因子之一,红光促进而远红光抑制种子萌发。光敏色素是调控种子萌发的主要光受体。活化的光敏色素诱导萌发主效抑制因子PIF1发生蛋白降解,调节赤霉素和脱落酸代谢和信号途径相关基因的表达,从而促进种子的萌发。同时,一系列的表观遗传因子通过改变染色质结构,动态调节萌发相关基因的表达从而影响种子的萌发进程。该论文重点论述了光调控种子萌发的转录及表观遗传机制研究进展,并对其在农业生产中的应用进行了展望。     

HD2C interacts with HDA6 and is involved in ABA and salt stress response in Arabidopsis

HD2 proteins are plant specific histone deacetylases. Four HD2 proteins, HD2A, HD2B, HD2C, and HD2D, have been identified in Arabidopsis. It was found that the expression of HD2A, HD2B, HD2C, and HD2D was repressed by ABA and NaCl. To investigate the function of HD2 proteins further, two HD2C T-DNA insertion lines of Arabidopsis, hd2c-1 and hd2c-3 were identified. Compared with wild-type plants, hd2c-1 and hd2c-3 plants displayed increased sensitivity to ABA and NaCl during germination and decreased tolerance to salt stress. These observations support a role of HD2C in the ABA and salt-stress response in Arabidopsis. Moreover, it was demonstrated that HD2C interacted physically with a RPD3-type histone deacetylase, HDA6, and bound to histone H3. The expression of ABA-responsive genes, ABI1 and ABI2, was increased in hda6, hd2c, and hda6/hd2c-1 double mutant plants, which was associated with increased histone H3K9K14 acetylation and decreased histone H3K9 dimethylation. Taken together, our results suggested that HD2C functionally associates with HDA6 and regulates gene expression through histone modifications.     

Transcriptome sequencing and metabolite profiling analyses provide comprehensive insight into molecular mechanisms of flower development in Dendrobium officinale (Orchidaceae)

Plant Molecular Biology - This research provides comprehensive insight into the molecular networks and molecular mechanisms underlying D. officinale flower development. Flowers are complex...     

Epigenetic interplay of histone modifications and DNA methylation mediated by HDA6

One of the most fundamental questions in the control of gene expression is how epigenetic patterns of DNA methylation and histone modifications are established. Our recent studies demonstrate that histone deacetylase HDA6 integrates DNA methylation and histone modifications in gene silencing by interacting with DNA methyltransferase MET1 and histone demethylase FLD, suggesting that regulatory crosstalk between histone modifications and DNA methylation could be mediated by the interaction of various epigenetic modification proteins.     

Histone Lysine Demethylases and Their Functions in Plants

Histone methylation—transfer of methyl groups to lysines or arginines residues of histone tails—plays an important role in the regulation of gene expression in eukaryotic cells. Histone methylation levels are regulated by histone methyltransferases and histone demethylases. There are two types of histone lysine demethylases (KDMs) in eukaryotes: KDM1/LSD1-like and JmjC domain-containing demethylases. KDMs can regulate gene expression directly through histone modification or indirectly through DNA methylation and siRNA regeneration. Recent studies indicate that KDMs play important regulatory roles in plant growth and developmental processes such as flowering time control, hormone response and circadian regulation.