Project description:Sugarcane is a very efficient crop to produce ethanol. In recent years, extensive efforts have been made in order to increase sugarcane yields. To reach this goal, molecular biology tools have been used comprehensively, identifying genes, pathways and genetic polymorphisms. However, some important molecular components, like microRNAs, have not been deeply investigated. MicroRNAs are an important class of endogenous small, noncoding RNAs that regulate gene expression at the post-transcription level and play fundamental roles in diverse aspects of animal and plant biology. Plant genomes harbor numerous miRNA genes that regulate many protein-coding genes to influence key processes ranging from development, metabolism, and responses to abiotic and biotic stresses. There is wide range of pests and diseases that affect sugarcane, yet the mechanisms that regulate pathogen interactions with sugarcane have not been thoroughly investigated. To gain knowledge on the physiological responses to pathogens mediated by microRNAs in sugarcane, we screened the transcriptoma of sugarcane plants infected with Acidovorax avenae subsp avenae, the causal agent of red stripe disease in sugarcane, and detected several microRNAs modulated in the presence of the pathogen. Furthermore, we validated with qPCR a number of microRNA expression patterns observed by bioinformatics analysis. In addition, we observed high expression levels of several star microRNAs, in numbers larger than the mature microRNAs in some cases. Interestingly, sof-miR408 was consistently down-regulated in the presence of several pathogens, but not in the presence beneficial microbes. This result indicates that the sugarcane senses pathogenic or beneficial microorganisms differentially and triggers specific epigenetic regulatory mechanisms accordingly
Project description:The present work aimed to compare the transcriptome of three major ethanol-producer Saccharomyces cerevisiae strains in Brazil when fermenting sugarcane juice for fuel ethanol production. This was motivated by the reports presenting physiological and genomics differences among them, and by the attempt to identify genes that could be related to their fermentation capacity and adaptation for different industrial processes.
Project description:Sugarcane is a very efficient crop to produce ethanol. In recent years, extensive efforts have been made in order to increase sugarcane yields. To reach this goal, molecular biology tools have been used comprehensively, identifying genes, pathways and genetic polymorphisms. However, some important molecular components, like microRNAs, have not been deeply investigated. MicroRNAs are an important class of endogenous small, noncoding RNAs that regulate gene expression at the post-transcription level and play fundamental roles in diverse aspects of animal and plant biology. Plant genomes harbor numerous miRNA genes that regulate many protein-coding genes to influence key processes ranging from development, metabolism, and responses to abiotic and biotic stresses. There is wide range of pests and diseases that affect sugarcane, yet the mechanisms that regulate pathogen interactions with sugarcane have not been thoroughly investigated. To gain knowledge on the physiological responses to pathogens mediated by microRNAs in sugarcane, we screened the transcriptoma of sugarcane plants infected with Acidovorax avenae subsp avenae, the causal agent of red stripe disease in sugarcane, and detected several microRNAs modulated in the presence of the pathogen. Furthermore, we validated with qPCR a number of microRNA expression patterns observed by bioinformatics analysis. In addition, we observed high expression levels of several star microRNAs, in numbers larger than the mature microRNAs in some cases. Interestingly, sof-miR408 was consistently down-regulated in the presence of several pathogens, but not in the presence beneficial microbes. This result indicates that the sugarcane senses pathogenic or beneficial microorganisms differentially and triggers specific epigenetic regulatory mechanisms accordingly Screenning of sRNA transcriptome of sugarcane plants infected with Acidovorax avenae subsp avenae after seven days
Project description:The present work aimed to compare the transcriptome of three major ethanol-producer Saccharomyces cerevisiae strains in Brazil when fermenting sugarcane juice for fuel ethanol production. This was motivated by the reports presenting physiological and genomics differences among them, and by the attempt to identify genes that could be related to their fermentation capacity and adaptation for different industrial processes. Two-condition experiment, T0h vs. T6h fermetations assay. Biological replicates: 3 T0h replicates, 5 T6h replicates.
Project description:Sugarcane is an economically important crop contributing to the world’s sugar and ethanol production with 80% and 40%, respectively. In recent years, the growing demands for sugar and ethanol production has prompted the necessity to increase sugarcane productivity through conventional breeding programs. However, sugarcane breeders have encountered several difficulties to raise productivity, mainly due to its complex genetics. Sugarcane has a polyploidy genome, with many varieties being aneuploidy. Today, the majority of the planted sugarcane cultivars are complex hybrids derived mainly from crosses between Saccharum officinarum and S. spontaneum. Therefore, proteomics can provide some insight into deciphering gene regulation and changes in carbon metabolism and sucrose accumulation in the culms at different stages of plant development. The aim of this work was to compare the quantitative changes of proteins in sugarcane culms, during plant growth and sucrose accumulation. Total proteins were isolated from both, juvenile and maturing internodes at three stages of plant development. Label free shotgun proteomics was used for protein profiling and quantification. The internodes 5 (I5) and 9 (I9) of 4, 7 and 10 month-old-plants (4M, 7M and 10M, respectively) were harvested and used for proteomic analyses. To mimic field conditions of sucrose accumulation during sugarcane maturation, we stopped watering 10M plants for 10 days. An average of 1130 proteins, unique and differentially expressed across all ages were identified and quantified. Proteins were categorized within 27 functional groups, related to biological process. The patterns of expression for some categories, such as cellular amino acids, metabolic processes, secondary metabolic processes and translation were down-regulated in the immature internode (I5-10M), while up-regulated in the mature I9-10M. We observed an increase in the abundance of several enzymes of the glycolytic pathway and isoforms of alcohol dehydrogenase (ADH) and pyruvate decarboxylase (PDC), in the juvenile stages of development of I9. These changes in enzymes contents indicates that at the early stages of internode development, hypoxia is increasing the glycolytic and ethanolic fermentation pathways, in order to supply ATP for plant growth and NAD+ for mitochondrial respiration, which might be impaired by the low oxygen availability inside the culm.
Project description:Sugarcane established industrial crop providing sugar, ethanol and biomass-derived electricity around the world. Cane sugar content is an important, breeding target, but its improvement remains very slow in many breeding programmes. Biotechnology strategies to improve sucrose accumulation made little progress at crop level, mainly due to the limited understanding of its regulation. MiRNAs regulate many metabolic processes in plants. However, their roles and target genes associated with sugarcane sucrose accumulation remains unknown. Here, we conducted high-throughput sequencing of transcriptome, small RNAs and degradome of leaves and stem of two sugarcane genotypes with contrasting sucrose content from the early to late stages of sucrose accumulation stages, which provided more insights into miRNA-associated gene regulation during sucrose accumulation. Transcriptome analysis identified 18,722 differentially expressed genes (DEGs) between both genotypes during sucrose accumulation. The major DEGs identified were involved in starch and sucrose metabolism, and photosynthesis etc. miRNA sequencing identified 563 known and 281 novel miRNAs from both genotypes during sucrose accumulation. Of these, 311 miRNAs were differentially expressed.752 targets of 368 miRNAs (609 targets for 260 known miRNAs and 168 targets for 108 novel miRNAs) were identified by degradom sequencing.Several known and novel miRNAs and their target genes associated with sugar metabolism, sugar transport and sucrose storage were identified in this study.This new insight into the complex network of sucrose accumulation in sugarcane will help identify candidate targets for sucrose improvement in sugarcane through molecular means.
Project description:Gas fermentation offers both fossil carbon-free sustainable production of fuels and chemicals and recycling of gaseous and solid waste using gas-fermenting microbes. Bioprocess development, systems-level analysis of biocatalyst metabolism, and engineering of cell factories are advancing the widespread deployment of the commercialised technology. Acetogens are particularly attractive biocatalysts but effects of the key physiological parameter – specific growth rate (μ) – on acetogen metabolism and the gas fermentation bioprocess have not been established yet. Here, we investigate the μ-dependent bioprocess performance of the model-acetogen Clostridium autoethanogenum in CO and syngas (CO+CO2+H2) grown chemostat cultures and assess systems-level metabolic responses using gas analysis, metabolomics, transcriptomics, and metabolic modelling. We were able to obtain steady-states up to μ ~2.8 day-1 (~0.12 h-1) and show that faster growth supports both higher yields and productivities for reduced by-products ethanol and 2,3-butanediol. Transcriptomics data revealed differential expression of 1,337 genes with increasing μ and suggest that C. autoethanogenum uses transcriptional regulation to a large extent for facilitating faster growth. Metabolic modelling showed significantly increased fluxes for faster growing cells that were, however, not accompanied by gene expression changes in key catabolic pathways for CO and H2 metabolism. Cells thus seem to maintain sufficient “baseline” gene expression to rapidly respond to CO and H2 availability without delays to kick-start metabolism. Our work advances understanding of transcriptional regulation in acetogens and shows that faster growth of the biocatalyst improves the gas fermentation bioprocess.