Role of epigenetic modifications in the development of crops essential traits.

Epigenetic modification refers to the chemical modifications of chromosomal DNA and histones, mainly including DNA methylation, histone modifications and non-coding RNAs. Without altering the DNA sequence, these heritable modifications can affect gene expression profiles by changing the chromatin state and play an important role in regulating the growth and development of plants. When the specific epigenetic modifications are changed, crops can obtain excellent phenotypes and stronger environmental adaptability. Therefore, artificially changing the epigenetic modifications are expected to obtain high-quality germplasm resources more suitable for agricultural production. In this review, we summarize the main types of plant epigenetic modifications, highlight the research progresses of functional plant epigenetic modifications on the important traits and responses to environmental stress, and identify the main problems that need be solved in the application of epigenetics in crop improvement, thereby providing new insights for the functional epigenetic modifications on crop breeding and improvement.

Multi-omics association analysis revealed the role and mechanism of epialleles in environmental adaptive evolution of Arabidopsis thaliana.

Epialleles, generally referring to alleles whose expression is altered due to differential DNA methylation levels, have important roles in plant morphology, development, and various physiological processes. However, the influence of environmental factors on the plant epialleles under natural conditions is unclear. Meanwhile, the role and mechanism of epialleles in the environmental adaptive evolution of plants remain elusive. In this study, we collected the transcriptome, methylome and climate data from 623 Arabidopsis accessions, derived from worldwide distributions. Then the data were subject to multi-omics association analysis combined with protein interaction network and gene enrichment analysis to identify epialleles related to specific environmental factors and to explore their possible mechanisms involved in the environmental adaptive evolution of Arabidopsis thaliana. We focused on spring and summer precipitation and identified five potential epialleles with differential DNA methylation levels located in specific regions of the genes: AGL36, AT2G34100, AT4G09360, LSU4 and AT5G56910. Interestingly, the imprinted gene AGL36 related to seed development was discovered as an epiallele involved in the environmental adaptive evolution of Arabidopsis thaliana, and the other four genes are related to the response to biotic stress. By protein interaction, GO enrichment, and KEGG pathway analysis, we also found that LSU4 may participate in the sulfur metabolism network like other members of the LSU gene family, and be involved in the biotic stress response by affecting glucosinolate metabolism. In natural conditions low precipitation may affect the severity of local pests and diseases. Therefore, we speculate that DNA methylation associates with the expression of the four genes to regulate the resistance of Arabidopsis thaliana to local pests and diseases, and ultimately participates in the adaptation to local environments.

[The application of two-dimensional liquid phase chromatography to separation of total protein of Leymus chinensis shoot].

The total proteins of Leymus chinensis were extracted from eight-week-old seedlings grown in the greenhouse by TCA-acetone precipitation method. After the lysis buffer was replaced by the start buffer, proteins were fractionated along the first dimension using chromatofocusing (CF). Subsequently the fractions with pI values between 8.5 and 4.0 collected after the first dimension separation were further fractionated by nonporous silica reverse-phase high-performance liquid chromatography (NPS-RP-HPLC, HPRP). With ProteoVue software the pI/UV map was generated to show the protein expression profile of Leymus chinensis. Some experiments were tested to optimize the fraction procedure. Three different elution gradients were employed to get the optimal chromatogram. Comparison of the protein expression pattern between 2D-PAGE and 2D-LC indicated that 2D-LC was a powerful tool in protein fraction. Reproducibility and veracity of the protein patterns were confirmed in different injections of the same sample. A method to fractionate the total protein of Leymus chinensis shoot with two-dimensional liquid chromatography (2D-LC) was founded.