Identification of responsive genes to multiple abiotic stresses in rice (Oryza sativa): a meta-analysis of transcriptomics data.

Abiotic stresses limit the quantity and quality of rice grain production, which is considered a strategic crop in many countries. In this study, a meta-analysis of different microarray data at seedling stage was performed to investigate the effects of multiple abiotic stresses (drought, salinity, cold situation, high temperature, alkali condition, iron, aluminum, and heavy metal toxicity, nitrogen, phosphorus, and potassium deficiency) on rice. Comparative analysis between multiple abiotic stress groups and their control groups indicated 561 differentially expressed genes (DEGs), among which 422 and 139 genes were up-regulated and down-regulated, respectively. Gene Ontology analysis showed that the process of responding to stresses and stimuli was significantly enriched. In addition, pathways such as metabolic process and biosynthesis of secondary metabolites were identified by KEGG pathway analysis. Weighted correlation network analysis (WGCNA) uncovered 17 distinct co-expression modules. Six modules were significantly associated with genes involved in response to abiotic stresses. Finally, to validate the results of the meta-analysis, five genes, including TIFY9 (JAZ5), RAB16B, ADF3, Os01g0124650, and Os05g0142900 selected for qRT-PCR analysis. Expression patterns of selected genes confirmed the results of the meta-analysis. The outcome of this study could help introduce candidate genes that may be beneficial for use in genetic engineering programs to produce more tolerant crops or as markers for selection.

Cell-Free Protein Synthesis from Exonuclease-Deficient Cellular Extracts Utilizing Linear DNA Templates.

Cell-free protein synthesis (CFPS) has recently become very popular in the field of synthetic biology due to its numerous advantages. Using linear DNA templates for CFPS will further enable the technology to reach its full potential, decreasing the experimental time by eliminating the steps of cloning, transformation, and plasmid extraction. Linear DNA can be rapidly and easily amplified by PCR to obtain high concentrations of the template, avoiding potential in vivo expression toxicity. However, linear DNA templates are rapidly degraded by exonucleases that are naturally present in the cell extracts. There are several strategies that have been proposed to tackle this problem, such as adding nuclease inhibitors or chemical modification of linear DNA ends for protection. All these strategies cost extra time and resources and are yet to obtain near-plasmid levels of protein expression. A detailed protocol for an alternative strategy is presented here for using linear DNA templates for CFPS. By using cell extracts from exonuclease-deficient knockout cells, linear DNA templates remain intact without requiring any end-modifications. We present the preparation steps of cell lysate from Escherichia coli BL21 Rosetta2 ΔrecBCD strain by sonication lysis and buffer calibration for Mg-glutamate (Mg-glu) and K-glutamate (K-glu) specifically for linear DNA. This method is able to achieve protein expression levels comparable to that from plasmid DNA in E. coli CFPS.

The automated Galaxy-SynBioCAD pipeline for synthetic biology design and engineering.

Here we introduce the Galaxy-SynBioCAD portal, a toolshed for synthetic biology, metabolic engineering, and industrial biotechnology. The tools and workflows currently shared on the portal enables one to build libraries of strains producing desired chemical targets covering an end-to-end metabolic pathway design and engineering process from the selection of strains and targets, the design of DNA parts to be assembled, to the generation of scripts driving liquid handlers for plasmid assembly and strain transformations. Standard formats like SBML and SBOL are used throughout to enforce the compatibility of the tools. In a study carried out at four different sites, we illustrate the link between pathway design and engineering with the building of a library of E. coli lycopene-producing strains. We also benchmark our workflows on literature and expert validated pathways. Overall, we find an 83% success rate in retrieving the validated pathways among the top 10 pathways generated by the workflows.

Chromosomal scale assembly of parasitic wasp genome reveals symbiotic virus colonization.

Endogenous viruses form an important proportion of eukaryote genomes and a source of novel functions. How large DNA viruses integrated into a genome evolve when they confer a benefit to their host, however, remains unknown. Bracoviruses are essential for the parasitism success of parasitoid wasps, into whose genomes they integrated ~103 million years ago. Here we show, from the assembly of a parasitoid wasp genome at a chromosomal scale, that bracovirus genes colonized all ten chromosomes of Cotesia congregata. Most form clusters of genes involved in particle production or parasitism success. Genomic comparison with another wasp, Microplitis demolitor, revealed that these clusters were already established ~53 mya and thus belong to remarkably stable genomic structures, the architectures of which are evolutionary constrained. Transcriptomic analyses highlight temporal synchronization of viral gene expression without resulting in immune gene induction, suggesting that no conflicts remain between ancient symbiotic partners when benefits to them converge.

Fluorescent Aminoglycoside Antibiotics and Methods for Accurately Monitoring Uptake by Bacteria.

Characterizing how multidrug-resistant bacteria circumvent the action of clinically used or novel antibiotics requires a detailed understanding of how the antibiotics interact with and cross bacterial membranes to accumulate in the cells and exert their action. When monitoring the interactions of drugs with bacteria, it remains challenging to differentiate functionally relevant internalized drug levels from nonspecific binding. Fluorescence is a method of choice for observing dynamics of biomolecules. In order to facilitate studies involving aminoglycoside antibiotics, we have generated fluorescently labeled aminoglycoside derivatives with uptake and bactericidal activities similar, albeit with a moderate loss, to those of the parent drug. The method combines fluorescence microscopy with fluorescence-activated cell sorting (FACS) using neomycin coupled to nonpermeable cyanine dyes. Fluorescence imaging allowed membrane-bound antibiotic to be distinguished from molecules in the cytoplasm. Patterns of uptake were assigned to different populations in the FACS analysis. Our study illustrates how fluorescent derivatives of an aminoglycoside enable a robust characterization of the three components of uptake: membrane binding, EDPI, and EDPII. Because EDPI levels are weak compared to the two other types of accumulation and critical for the action of these drugs, the three components of uptake must be taken into account separately when drawing conclusions about aminoglycoside function.

New single nucleotide polymorphism G5508A in the SEPT12 gene may be associated with idiopathic male infertility in Iranian men.

BACKGROUND: Male infertility is a multifactorial disorder, which affects approximately 10% of couples at childbearing age with substantial clinical and social impact. Genetic factors are associated with the susceptibility to spermatogenic impairment in humans. Recently, SEPT12 is reported as a critical gene for spermatogenesis. This gene encodes a testis specific member of Septin proteins, a family of polymerizing GTP-binding proteins. SEPT12 in association with other Septins is an essential annulus component in mature sperm. So, it is hypothesized that genetic alterations of SEPT12 may be concerned in male infertility. OBJECTIVE: The objective of this research is exploration of new single nucleotide polymorphism G5508A in the SEPT12 gene association with idiopathic male infertility in Iranian men. MATERIALS AND METHODS: In this case control study, 67 infertile men and 100 normal controls were analyzed for genetic alterations in the active site coding region of SEPT12, using polymerase chain reaction sequencing technique. Fisher exact test was used for statistical analysis and p<0.05 was considered as statistically significant. RESULTS: Genotype analysis indicated that G5508A polymorphic SEPT12 alleles were distributed in three peaks of frequency in both control and diseases groups. Categorization of the alleles into (GG), (GA), (AA) types revealed a significant difference between infertile patients (azoospermic and asthenospermic) and normal controls (p=0.005). CONCLUSION: According to our finding we suggest that G5508A polymorphism in SEPT12 gene can affect spermatogenesis in men, the opinion needs more investigation in different populations.

Relationship between absence of annulus and asthenozoospermia in Iranian men.

PURPOSE: To find a relationship between absence of annulus and asthenozoospermia in Iranian men. METHODS: In the present study, semen samples from 100 asthenozoospermic and 20 normozospermic patients were analyzed for sperm concentration and motility. Spermatozoa were immunostained for the two septin subunits Sept4 and Sept7. The absence of the annulus structure was confirmed by transmission electron microscopy and western blot analysis for septin 4. DNA sequencing for all coding exons of SEPT12 was performed for a patient using peripheral blood sample. RESULTS: Specific antibodies for SEPT4 and SEPT7 consistently labeled the annuli in spermatozoa from all of the 20 normozospermic men, while in one of 100 patients with asthenozoospermia, 75% of sperms lacking septin 4 or septin 7 proteins at the annulus. It was shown that the structural defect in annulus formation is not caused by point mutation of SEPT12 gene. CONCLUSIONS: In conclusion, the results of this study demonstrated that the frequency of the absence of annulus in asthenozoospermic sample of Iranian population has a low frequency and could not be assume as a diagnostic marker for classifying asthenozoospermic patients.