Project description:Background: Pollen, the male partner in the reproduction of flowering plants, comprises either two or three cells at maturity. The current knowledge of the pollen transcriptome is limited to the model plant Arabidopsis thaliana, which has tri-cellular pollen grains at maturity. Comparative studies on pollen of other genera, particularly crop plants, are needed to understand the pollen gene networks that are subject to functional and evolutionary conservation. In this study, we used the Affymetrix Soybean GeneChip® to perform transcriptional profiling on mature bi-cellular soybean pollen. Results: Compared to the sporophyte transcriptome, the soybean pollen transcriptome revealed a restricted and unique repertoire of genes, with a significantly greater proportion of specifically expressed genes than is found in the sporophyte tissue. Comparative analysis shows that, among the 37,500 soybean unique transcripts addressed in this study, 10,299 genes (27.46%) are expressed in pollen. Of the pollen-expressed genes, about 9,489 (92.13%) are also expressed in sporophytic tissues, and 810 (7.87%) are selectively expressed in pollen. Overall, the soybean pollen transcriptome shows an enrichment of transcription factors (mostly zinc finger family proteins), cell cycle-related transcripts, signal recognition receptors, ethylene responsive factors, chromatin remodeling factors, and members of the ubiquitin proteasome proteolytic pathway. Moreover, we identify several new pollen-specific candidate genes that might play a significant role in pollen biology. Conclusion: This is the first report of a soybean pollen transcriptional profile. These data extend our current knowledge regarding regulatory pathways that govern the gene regulation and development of pollen. We also demonstrate that pollen is a rich store of regulatory proteins that are essential and sufficient for de novo gene expression. A comparison between transcription factors up-regulated in soybean and those upregulated in Arabidopsis revealed some divergence in the numbers and kinds of regulatory proteins expressed in both species.
Project description:Tropospheric ozone (O3) is a secondary air pollutant and anthropogenic greenhouse gas. Concentrations of tropospheric O3 have more than doubled since the Industrial Revolution, and are high enough to damage plant productivity. Soybean (Glycine max L. Merr.) is the worldâs most important legume crop and is sensitive to O3. Current ground-level O3 are estimated to reduce global soybean yields by 6% to 16%. In order to understand transcriptional mechanisms of yield loss in soybean, we examined the transcriptome of soybean flower and pod tissues exposed to elevated O3 using RNA-Sequencing.
Project description:Chilling stress is a major factor limiting the yield and quality of vegetable soybean (Glycine max L.) on a global scale. Systematic identification and function analysis of miRNA under chilling stress could be helpful to clarify the molecular mechanism of chilling resistance. In the present study, two independent small RNA libraries from leaves of vegetable soybean were constructed, and sequenced with the high-throughput Illumina Solexa system. A total of 434 known miRNAs and three novel miRNAs were identified. Moreover, the expression patterns of these miRNAs have been verified by qRT-PCR analysis. Furthermore, we identified their gene targets by high-throughput degradome sequencing and validated using 5'-RACE. A total of 898 transcripts were targeted by 54 miRNA families attributed to five categories. More importantly, we identified 55 miRNAs that differentially expressed between chilling stress and the control. The targets of these miRNAs were enriched in oxidation-reduction, signal transduction, and metabolic process functional categories. The qRT-PCR confirmed that there was a negative relationship among the miRNAs and their targets under chilling stress. Our work provides comprehensive molecular evidence for the possible involvement of miRNAs in the process of chilling-stress responses in vegetable soybean.
Project description:RNA-seq was used to characterize gene expression in soybean from a wide range of tissues. The primary focus of the project was small RNAs, and the identification of microRNAs and phased siRNA-generating loci, but RNA-seq data were generated from the same samples. This project was supported by the United Soybean Board.
Project description:Intercropping is a sustainable agricultural practice widely used around the world for enhancing resource use efficiency. However, short crops often grow in shade condition underneath the canopy of tall crops. Soybean is one of the most important oil crops and usually is planted in intercropping patterns. However, little is known about the acclimation responses of soybean leaves to shade in intercropping condition at the transcriptome level.
Project description:Soybean (Glycine max) seeds are an important source of seed storage compounds, including protein, oil, and sugar used for food, feed, chemical, and biofuel production. We assessed detailed temporal transcriptional and metabolic changes in developing soybean embryos to gain a systems biology view of developmental and metabolic changes and to identify potential targets for metabolic engineering. Two major developmental and metabolic transitions were captured enabling identification of potential metabolic engineering targets specific to seed filling and to desiccation. The first transition involved a switch between different types of metabolism in dividing and elongating cells. The second transition involved the onset of maturation and desiccation tolerance during seed filling and a switch from photoheterotrophic to heterotrophic metabolism. Clustering analyses of metabolite and transcript data revealed clusters of functionally related metabolites and transcripts active in these different developmental and metabolic programs. The gene clusters provide a resource to generate predictions about the associations and interactions of unknown regulators with their targets based on guilt-by-association relationships. The inferred regulators also represent potential targets for future metabolic engineering of relevant pathways and steps in central carbon and nitrogen metabolism in soybean embryos and drought and desiccation tolerance in plants.
Project description:Soybean (Glycine max) seeds are an important source of seed storage compounds, including protein, oil, and sugar used for food, feed, chemical, and biofuel production. We assessed detailed temporal transcriptional and metabolic changes in developing soybean embryos to gain a systems biology view of developmental and metabolic changes and to identify potential targets for metabolic engineering. Two major developmental and metabolic transitions were captured enabling identification of potential metabolic engineering targets specific to seed filling and to desiccation. The first transition involved a switch between different types of metabolism in dividing and elongating cells. The second transition involved the onset of maturation and desiccation tolerance during seed filling and a switch from photoheterotrophic to heterotrophic metabolism. Clustering analyses of metabolite and transcript data revealed clusters of functionally related metabolites and transcripts active in these different developmental and metabolic programs. The gene clusters provide a resource to generate predictions about the associations and interactions of unknown regulators with their targets based on “guilt-by-association” relationships. The inferred regulators also represent potential targets for future metabolic engineering of relevant pathways and steps in central carbon and nitrogen metabolism in soybean embryos and drought and desiccation tolerance in plants. SUBMITTER_CITATION: Biology 2013, 2(4), 1311-1337; doi:10.3390/biology2041311 Changes in RNA Splicing in Developing Soybean (Glycine max) Embryos Delasa Aghamirzaie, Mahdi Nabiyouni, Yihui Fang, Curtis Klumas, Lenwood S. Heath, Ruth Grene and Eva Collakova SUBMITTER_CITATION: Metabolites 2013, 3(2), 347-372; doi:10.3390/metabo3020347 Metabolic and Transcriptional Reprogramming in Developing Soybean (Glycine max) Embryos Eva Collakova, Delasa Aghamirzaie, Yihui Fang, Curtis Klumas, Farzaneh Tabataba, Akshay Kakumanu, Elijah Myers, Lenwood S. Heath and Ruth Grene Total mRNA profiles of 10 time course samples of Soybean developing embryos with three replicates per sample were generated by deep sequencing, using Illumina HiSeq 2000