Project description:Background: RNA interference (RNAi) is an indispensable regulatory mechanism governing developmental processes and stress responses via sequence-specific control of target RNAs mediated by the action of small, 20–24-nt-long, non-coding regulatory (s)RNAs such as micro (mi) and small interfering (si) RNAs. Biogenesis and sorting of miRNAs into ARGONAUTE (AGO) proteins are intensively investigated, however very few information is available about the presence and distribution of distinct sRNA pools in plant cells. Results: High-throughput sequencing of size-separated sRNA pools of plant crude extracts revealed that the majority of the canonical miRNAs were associated with high molecular weight RNA-induced silencing complexes co-migrating with AGO1 (HMW RISC). In contrast, the majority of 24-nt-long siRNAs were found in association with low molecular weight complexes co-migrating with AGO4 (LMW RISC). Intriguingly, we identified a large set of sRNAs in the cytoplasm, including mature miRNA sequences, in the low molecular size range corresponding to protein-unbound sRNAs. By comparing the RISC-loaded and protein-unbound pools of miRNAs, we identified miRNAs with highly different loading efficiencies. Investigation of some selected miRNAs in a transient expression system validated this finding. We also showed that the availability of RISCs is a limiting factor determining the loading efficiency of miRNAs. Conclusion: Our data reveal the existence of a regulatory checkpoint, likely controlled by information carried by the diverse miRNA precursors, determining the RISC-loading efficiencies of various miRNAs by sorting only a subset of the produced miRNAs into the biologically active RISCs.
Project description:The success of bottom-up proteomic analysis frequently depends on the efficient removal of contaminants from protein or peptide samples before LC-MS/MS. For a peptide clean-up workflow, the single-pot solid-phase-enhanced peptide sample preparation on carboxylate-modified paramagnetic beads (termed SP2) was evaluated for sodium dodecyl sulfate or polyethylene glycol removal from Arabidopsis thaliana tryptic peptides. The robust and efficient 40-min SP2 protocol, tested for a 10 ng, 250ng and 10µg peptide sample, was proposed and benchmarked thoroughly against the ethyl acetate extraction protocol. The SP2 protocol on carboxylated magnetic beads proved to be the robust approach even for simultaneous removal of massive sodium dodecyl sulfate (SDS) and polyethylene glycol (PEG) contaminations from AT peptide samples in respect of the LC-MS/MS data outperforming ethyl acetate extraction.
Project description:This dataset has been used to establish GroEL-proteotyping, a targeted proteotyping approach for assessing bacterial community compositions using the taxonomic marker protein GroEL. This dataset contains raw data of two experiments: 1. Pure cultures of T. aromatica (sample names: TA, TB, TC) and P. putida (sample names: PA, PB, PC) were analyzed individually after in-solution digestion 2. T. aromatica and P. putida were cultivated independently and crude extracts were mixed in defined ratios. GroEL was pre-separated by SDS-PAGE (sample names: LOD_..., in-gel digestion)
Project description:Enzymatic Methyl-seq (EM-seq) is an enzyme-based method giving us reliable methylome data from small amounts of purified DNA. However, it is unclear whether EM-seq library can be constructed from crude cell lysate containing genomic DNA. We evaluated the quality of EM-seq libraries directly prepared from crude cell lysate.
Project description:Medicinal plants are potential sources for a wide range of complex compounds with probable anticancer activity. Ephedra foeminea Forssk. (E. foeminea), a medicinal plant found in the Eastern Mediterranean, has recently been gaining popularity as a cancer remedy; there is, however, a paucity of empirical evidence supporting this claim. In this study, the effect of E. foeminea ethyl acetate, ethanol, and water crude extracts on viability, migratory ability, and the steady-state mRNA levels of genes involved in these processes was, respectively, examined using MTT assay, wound healing assay, and reverse transcriptase PCR (RT-PCR). The study concludes that all extracts significantly reduce human osteosarcoma U2OS percentage viability in a dose- and time-dependent manner, with varying potencies. The least half-maximal inhibitory concentration (IC50) was observed in the water extract after 48 h incubation (30.761 ± 1.4 μg/mL) followed by the ethyl acetate extract after 72 h incubation (80.35 ± 1.233 μg/mL) and finally the ethanol extract after 48 h incubation (97.499 ± 1.188 μg/mL). Ethanol extract significantly reduced U2OS percentage wound closure. On the other hand, both ethanol and water extracts considerably reduced the steady-state mRNA expression of beta-catenin, promoting both cell proliferation and migration in osteosarcoma by regulating target genes. Additionally, E. foeminea showed no hemolytic activity. These effects suggest that E. foeminea decreases U2OS cell viability and migratory ability by modulating the expression of critical genes involved in regulating these processes and is likely cytocompatible with human erythrocytes.
Project description:Because propolis contains many types of antioxidant compounds such as polyphenols and flavonoids, it can be useful in preventing oxidative damages. Ethyl acetate extracts of propolis from several Algerian regions show high activity by scavenging free radicals, preventing lipid peroxidation and inhibiting myeloperoxidase (MPO). By fractioning and assaying ethyl acetate extracts, it was observed that both polyphenols and flavonoids contribute to these activities. A correlation was observed between the polyphenol content and the MPO inhibition. However, it seems that kaempferol, a flavonoid, contributes mainly to the MPO inhibition. This molecule is in a high amount in the ethyl acetate extract and demonstrates the best efficiency towards the enzyme with an inhibiting concentration at 50% of 4 ± 2 µM.