Global Analysis of Differentially Expressed Genes and Proteins in the Wheat Callus Infected by Agrobacterium tumefaciens

Agrobacterium-mediated plant transformation is an extremely complex and evolved process involving genetic determinants of both the bacteria and the host plant cells. However, the mechanism of the determinants remains obscure, especially in some cereal crops such as wheat, which is recalcitrant for Agrobacterium-mediated transformation. In this study, differentially expressed genes (DEGs) and differentially expressed proteins (DEPs) were analyzed in wheat callus cells co-cultured with Agrobacterium by using RNA sequencing (RNA-seq) and two-dimensional electrophoresis (2-DE) in conjunction with mass spectrometry (MS). A set of 4,889 DEGs and 90 DEPs were identified, respectively. Most of them are related to metabolism, chromatin assembly or disassembly and immune defense. After comparative analysis, 24 of the 90 DEPs were detected in RNA-seq and proteomics datasets simultaneously. In addition, real-time RT-PCR experiments were performed to check the differential expression of the 24 genes, and the results were consistent with the RNA-seq data. According to gene ontology (GO) analysis, we found that a big part of these differentially expressed genes were related to the process of stress or immunity response. Several putative determinants and candidate effectors responsive to Agrobacterium mediated transformation of wheat cells were discussed. We speculate that some of these genes are possibly related to Agrobacterium infection. Our results will help to understand the interaction between Agrobacterium and host cells, and may facilitate developing efficient transformation strategies in cereal crops.     

金针菇成熟期和伸长期菌盖的转录组与蛋白组比较分析

菌盖是大型真菌的重要组成部分,也是其产生有性孢子的部位,但是其发育机制仍不明确。本研究以金针菇Flammulina filiformis为材料,采用转录组和蛋白组联合分析的方法,比较分析了金针菇成熟期和伸长期菌盖的差异基因与蛋白,并对其进行GO (gene ontology)功能聚类分析、KEGG (Kyoto encyclopedia of genes and genomes)富集分析和蛋白互作网络分析。本研究筛选到差异表达基因有1 391个,差异表达蛋白147个,均以上调表达为主。GO功能聚类分析结果表明,催化活性(catalytic activity)条目富集基因最多,其次是细胞组分(cell part)、细胞过程(cellular process)和细胞器(organelle)。KEGG富集分析结果表明,差异表达基因和蛋白主要富集在碳水化合物代谢通路(carbohydrate metabolism)和氨基酸代谢通路(amino acid metabolism)等。本研究选取了9个关键的差异表达基因,使用实时荧光定量PCR (real-time quantitative PCR,RT-qPCR)对其表达量进行了验证。RT-qPCR验证结果与转录组测序结果相一致。蛋白互作网络分析表明,水解酶类、结构域类和转录调节类蛋白为互作网络的主要结点。本研究联合转录组、蛋白组测序数据,通过分析差异基因与蛋白,为深入了解金针菇菌盖发育机制提供数据参考。     

Differences in hepatic gene expression as a major distinguishing factor between Korean native pig and Yorkshire

There are phenotypic differences between Korean native pig (KNP) and Yorkshire (YS) breeds due to different interests in selection. YS has been selected for industrial interests such as a growth rate and lean meat production, while KNP has been maintained as a regional breed with local interests such as disease resistance and fat content in and between muscle. A comparison of gene expression profiles from liver tissue reflected overall long-term effects of artificial selection for these two pig breeds. Based on minimum positive false discovery rate (less than 10%) and fold change (|FC|>1.5), 73 differentially expressed genes (DEGs) were identified. Functional analysis of these DEGs indicated clear distinctions in signaling capacity related to epidermal growth factor (EGF), extracellular structure, protein metabolism, and detoxification. Hepatic DEGs demonstrated the importance of hormonal and metabolic capabilities to differences between these two pig breeds.     

Transcriptional alteration of p53 related processes as a key factor for skeletal muscle characteristics in <Emphasis Type="Italic">Sus scrofa</Emphasis>

The pig could be a useful model to characterize molecular aspects determining several delicate phenotypes because they have been bred for those characteristics. The Korean native pig (KNP) is a regional breed in Korea that was characterized by relatively high intramuscular fat content and reddish meat color compared to other western breeds such as Yorkshire (YS). YS grew faster and contained more lean muscle than KNP. We compared the KNP to Yorksire to find molecular clues determining muscle characteristics. The comparison of skeletal gene expression profiles between these two breeds showed molecular differences in muscle. We found 82 differentially expressed genes (DEGs) defined by fold change (more than 1.5 fold difference) and statistical significance (within 5% of false discovery rate). Functional analyses of these DEGs indicated up-regulation of most genes involved in cell cycle arrest, down-regulation of most genes involved in cellular differentiation and its inhibition, down-regulation of most genes encoding component of muscular-structural system, and up-regulation of most genes involved in diverse metabolism in KNP. Especially, DEGs in above-mentioned categories included a large number of genes encoding proteins directly or indirectly involved in p53 pathway. Our results indicated a possible role of p53 to determine muscle characteristics between these two breeds.