Project description:Background: Microorganisms are the major cause of food spoilage during storage, processing and distribution. Pseudomonas fluorescens is a typical spoilage bacterium that contributes to a large extent to the spoilage process of proteinaceous food. RpoS is considered an important global regulator involved in stress survival and virulence in many pathogens. Our previous work revealed that RpoS contributed to the spoilage activities of P. fluorescens by regulating resistance to different stress conditions, extracellular acylated homoserine lactone (AHL) levels, extracellular protease and total volatile basic nitrogen (TVB-N) production. However, RpoS-dependent genes in P. fluorescens remained undefined. Results: RNA-seq transcriptomics analysis combined with quantitative proteomics analysis basing on multiplexed isobaric tandem mass tag (TMT) labeling was performed for the P. fluorescens wild-type strain UK4 and its derivative carrying a rpoS mutation. A total of 375 differentially expressed genes (DEGs) and 212 differentially expressed proteins (DEPs) were identified in these two backgrounds. The DGEs were further verified by qRT-PCR tests, and the genes directly regulated by RpoS were confirmed by 5’-RACE-PCR sequencing. The combining transcriptome and proteome analysis revealed a role of this regulator in several cellular processes, including polysaccharide metabolism, intracellular secretion and extracellular structures, cell well biogenesis, stress responses, ammonia and biogenic amine production, which may contribute to biofilm formation, stress resistance and spoilage activities of P. fluorescens. Moreover, in this work we indeed observed that RpoS contributed to the production of the macrocolony biofilm’s matrix.
Project description:We found that assassin bugs from the earliest-diverging subfamily of higher Reduviidae (Peiratinae), as well as a subfamily closely related to Triatominae (Stenopodainae) have venom that is highly similar in composition to that produced by previously examined reduviids from Harpactorinae and Reduviinae. This finding suggests that venom composition has been largely stable due to purifying selection among the higher Reduviidae, which is consistent with the ancient origin of venom in the ancestors of Heteroptera 250–300 million years ago (Sunagar and Moran 2015; Walker et al. 2018a). This near homogeneity of venom composition is perhaps surprising considering that reduviid predators have evolved numerous instances of prey specialization and specialized hunting strategies that might be expected to co-evolve with venom. Possibly, further studies focussing on species with more specialized hunting strategies, or different kinds of venom bioactivities, will uncover more nuanced venom adaptations. Alternatively, it is possible that the protease-rich venoms of predatory reduviids are simply well-suited to myriad different hunting strategies. These data are consistent with other examples where venoms are surprisingly similar despite great differences in biology, for example between solitary and eusocial bees. A more detailed picture of venom evolution in Reduviidae would examine venom produced by the early-diverging Phymatine complex as well as venoms of non-reduviid cimicomorphs, prey specialists such as the arachnophagous Emesinae and the myrmecophagous Holoptilinae, and some of the many groups that employ hunting specializations, such as the use of plant resins to catch prey (Hwang and Weirauch 2012). Within Triatominae, examination of saliva produced by additional species from multiple lineages (especially those that switched to blood-feeding independently, if the subfamily is shown to be polyphyletic) and including generalists and specialists on different host taxa and species associated especially with nests and burrows will be informative. The venoms of predatory reduviids such as Zelurus spp. and Opisthacidius spp. that are most closely related to Triatominae, and share some behaviours such as habitation of bird nests by Opisthacidius spp. may also provide more information about the evolution of triatomine saliva.
Project description:Pseudomonas aeruginosa is an opportunistic pathogen that requires iron for growth and virulence, yet this nutrient is sequestered by the innate immune system during infection. When iron is limiting, P. aeruginosa expresses the PrrF1 and PrrF2 small regulatory RNAs (sRNAs), which post-transcriptionally repress expression of non-essential iron-containing proteins thus sparing this nutrient for more critical processes.The genes for the PrrF1 and PrrF2 sRNAs are arranged in tandem on the chromosome, allowing for the transcription of a longer heme-responsive sRNA, termed PrrH. While the functions of PrrF1 and PrrF2 have been studied extensively, the role of PrrH in P. aeruginosa physiology and virulence is not well understood. In this study, we performed transcriptomic and proteomic studies to identify the PrrH regulon.
Project description:To investigate the usefulness of gene expression as diagnostic biomarkers, we compared whole genome expression profiles of lumbar spinal cord with profiles of peripheral blood and tibialis anterior muscle in 16 mutant G93A-SOD1 mice and 15 wild type littermates. Total RNA obtained from blood, tibialis anterior muscle and lumbar spinal cord of G93A-SOD1 mice compared to wild type littermates.
Project description:Urea can serve as nitrogen source for coral holobionts and plays a cruscial role in coral calcification, although the degradation of urea by coral symbionts is not fully understood. In this study, we investigated the urea utilized pathway and the responses of the Symbiodiniaceae family to urea under high temperature conditions. Genome screening revealed that all Symbiodiniaceae species contain the urease (URE) and DUR2 subunit of urea amidolyase (UAD) system. However, only three speciesCladocopium goreaui, Cladopium c92, and Symbiodinium pilosum possess a complete UAD system, including both DUR1 and DUR2. Phylogentic analyses revealed that the UAD system in Symbiodiniaceae clusters more closely with symbiotic bacteria, indicating that horizontal gene transfer of UAD system has occured in coral symbionts. Physiology analysis showed that the symbiodiniacean species Cladocopium goreaui, which containing both URE and UAD, grew better under urea than ammonium conditions, as indicated by higher maximum specific growth rates. Furthermore, most genes of Symbiodiniaceae involved in urea utilization appeared to be stable under various conditions such as heat stress (HS), low light density, and nitrogen deficiency, wheras in ammonium and nitrate transporters were significantly regulated. These relatively stable molecular regulatory properties support sustained urea absorption by Symbiodiniaceae, as evidenced by an increase in δ15N2-urea absorption and the decreases in δ5N-NO3-, and δ15N-NH4+ from cultural environment to Symbiodiniaceae under HS conditions. Token together, this study reveals two distinct urea utilization systems in coral ecosystem and highlights the importance of the urea cycle in coral symbionts when facing fluctuating nitrogen environment in future warming ocean.
Project description:The clinical presentation, course and treatment of methamphetamine-associated psychosis (MAP) are similar to that observed in schizophrenia (SCZ) and subsequently MAP has been hypothesized as a pharmacological and environmental model of SCZ. However, several challenges currently exist in accurately diagnosing MAP at the molecular and neurocognitive level before the MAP model can contribute to the discovery of SCZ biomarkers. We directly assessed subcortical brain structural volumes and clinical parameters of MAP within the framework of an integrative genome-wide RNA-Seq blood transcriptome analysis of subjects diagnosed with MAP (N=10), METH-dependency without psychosis (MA) (N=10) and healthy controls (N=10). We used RNA-Sequencing gene expression to characterize molecular signatures associated to METH and MAP status compared to healthy control subjects. Peripheral blood luekocytes gene expression was subject to transcriptional analysis for 10 MAP subjects, 10 subjects with METH-dependency without psychotic symptomics and 10 healthy controls.
Project description:Light spectrum quality is an important signal for plant growth and development. We aimed to analyze the effects of different light spectra on in vitro shoot development and proteomic and polyamine (PA) profiles in shoots of Cedrela fissilis. Cotyledonary and apical nodal segments were grown under different light emitting diode (LED) lamps and a fluorescent lamp. Shoots from cotyledonary nodal segments cultured with 6-benzyladenine (BA) grown under WmBdR LED increased their length, fresh and dry matter compared to shoots grown under fluorescent light. A non-redundant protein databank generated by transcriptome sequencing and de novo assembly of C. fissilis improved, and almost doubled, protein identification compared to a Citrus sinensis databank. Using the C. fissilis protein databank, a total of 616 proteins were identified, with 23 up- and 103 downaccumulated in shoots under WmBdR LED compared to fluorescent lamp. Differential accumulation of argininosuccinate synthase protein was associated with an increase in free-Put contents and, consequently, with higher shoot elongation under WmBdR LED. Furthermore, the proteins S-adenosylmethionine synthase, which is related to PA and ethylene biosynthesis, and 1-aminocyclopropane-1-carboxylate oxidase, related to ethylene biosynthesis, were unique in shoots grown under fluorescent lamp, showing lower elongation of shoots, possibly due to ethylene production. The downaccumulation of calreticulin, heat shock proteins, plastid-lipid-associated protein, ubiquitin-conjugating enzymes, and ultraviolet-B receptor UVR8 isoform X1 could be related to better shoot length under LED. This work provides important data related to the effects of light spectrum quality on in vitro morphogenesis via modulation of specific proteins and free-Put biosynthesis.
Project description:In a previous study, we found that H2S alleviates salinity stress in cucumber by maintaining the Na+/K+ balance and by regulating H2S metabolism and the oxidative stress response. However, little is known about the molecular mechanisms behind H2S-regulated salt-stress tolerance in cucumber. Here, an integrated transcriptomic and proteomic analysis based on RNA-seq and 2-DE was used to investigate the global mechanism underlying H2S-regulated salt-stress tolerance. In total, 11 761 differentially expressed genes (DEGs) and 61 differentially expressed proteins (DEPs) were identified. Analysis of the pathways associated with the DEGs showed that salt stress enriched expression of genes in primary and energy metabolism, such as photosynthesis, carbon metabolism and biosynthesis of amino acids. Application of H2S significantly decreased these DEGs but enriched DEGs related to plant-pathogen interaction, sulfur-containing metabolism, cell defense and signal transduction pathways. Notably, changes related to sulfur-containing metabolism and cell defense were also observed through proteome analysis, such as Cysteine synthase 1, Glutathione S-transferase U25-like, Protein disulfide-isomerase and Peroxidase 2. We present the first global analysis of the mechanism underlying H2S regulation of salt-stress tolerance in cucumber through tracking changes in the expression of specific proteins and genes.
Project description:Ananas comosus var. bracteatus has high ornamental value and widespread application because of its chimeric leaves. However, little is known about the molecular mechanism regulating this characteristic. Here, comparative transcriptomic and proteomic analyses of the white parts (Whs) and green parts (Grs) of the chimeric leaves were performed to identify differentially expressed genes (DEGs) and differentially expressed proteins (DEPs). In total, 1,685 DEGs, including 712 up- and 973 down-regulated ones, and 5,428 DEPs, including 1,018 up- and 795 down-regulated ones, were identified between the Whs and Grs. Comparisons with the GO and KEGG annotations revealed that the DEGs were involved mostly in carbon fixation, porphyrin and chlorophyll metabolism and oxidative phosphorylation. The DEPs were mainly involved in ribosomes, photosynthesis, photosynthesis antennas, and porphyrin and chlorophyll metabolism. Combined analysis showed that nine proteins related to chlorophyll biosynthesis, photosynthetic pigments, and photosynthesis were unchanged at mRNA level but suppressed at protein level. These results indicated that the albino phenotype of the Whs was caused by the proteomic-level suppression of key enzymes involved in the chlorophyll biosynthesis pathway and that translational and post-translational regulation may play important roles in both the biosynthesis of photosynthetic pigments and photosynthesis. Biological significance: Leaves of Ananas comosus var. bracteatus serve as the best materials for the study of albino mechanism. Because the chemic trait of A. comosus var. bracteatus is unstable and the molecular mechanism of the albino cells was poorly understood, we performed comparative analyses both at the transcriptome and proteome levels. This work revealed suppressed proteomic-level and translational and post-translational regulation contribute to the albino phenotype formation. Our results provide better information concerning the molecular mechanism within the chimeric leaves of A. comosus var. bracteatus.
Project description:We report genome-wide maps of transcription in mouse erythroid cells. We used an approach to survey poly(A)+ (mRNA) (GSE26877) and non-polyadenylated RNA poly(A)- (GSE27920) separately. This provides an alternative framework for comprehensive transcriptome profiling in mammalian cells. Two Samples. mRNA-seq from wild type murine Ter119+ cells and mRNA-seq from ?MCS-P6MCS-R3-/- Ter119+ cells