Multiple traits of agronomic importance in transgenic indica rice plants: analysis of transgene integration patterns,expression levels and stability

We cotransformed indica rice (Oryza sativa L. cvs. Basmati 370 and M7) with three plasmids, carrying a total of four genes, by particle bombardment. The Bacillus thuringiensis (Bt) -endotoxin genes cry1Ac and cry2A were carried on separate vectors, while the gna (snowdrop lectin) and hpt (hygromycin phosphotransferase) genes were linked on the same, cointegrate vector. We evaluated the molecular and expression profiles of 29 independently derived transgenic lines over two generations. The gna and hpt genes cointegrated with a frequency of 100% as expected. Furthermore, 60% of the transgenic plants carried all four genes. Southern blot analysis showed that transgene copy number ranged from 1 to 15. We used western blots to determine protein expression levels in R₀ and R₁ plants. We observed wide variation in the expression levels of the nonselected transgenes among independently-derived lines, but expression levels within lines derived from the same clone were similar. Consistent with previous reports, we observed no correlation between transgene copy number and the level or stability of protein expression. We show that the introduction of multiple agronomically valuable genes into the rice genome by cotransformation is a practical strategy for engineering elite rice varieties.     

Conformational Analysis of Nucleosides Constructed on a Bicyclo[3.1.0]hexane Template. Structure-Antiviral Activity Analysis for the Northern and Southern Hemispheres of the Pseudorotational Cycle

Abstract

A conformational analysis of carbocyclic nucleosides built on a rigid bicyclo[3.1.0]hexane template (1–4, Northern and 5–8 Southern) showed that the Northern conformation prefers an anti glycosyl torsion angle whereas the Southern conformation favors the syn range. Antiviral activity was mostly associated with the Northern conformers.     

Tyrosine-1 of RNA Polymerase II CTD Controls Global Termination of Gene Transcription in Mammals

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PRDM16, LRP1 and TRPM8 genetic polymorphisms are risk factor for Pakistani migraine patients

BackgroundMigraine is a chronic neurovascular condition characterized by recurring attacks of pulsating headaches. Genome-wide association studies (GWAS) identified many potential loci associated with migraine. To check the association of polymorphisms of PRDM16 (rs2651899), LRP1 (rs11172113), and TRPM8 (rs10166942) with migraine, the first time a case-control study was conducted in understudied Pakistani population.MethodsThe study included 127 migraine patients (21 in migraine with aura and 106 with migraine without aura group) and 120 healthy control subjects from different areas of Punjab, Pakistan. Blood samples were collected from all the participants, and DNA was isolated from the lymphocytes by the modified organic method. Sanger’s sequencing was done for PRDM16 (rs2651899), LRP1 (rs11172113), and TRPM8 (rs10166942) in all the samples to check the genotype. Logistic regression analysis was done using SPSS 20.0 to check the association of these SNPs with migraine susceptibility.ResultsWe found statistically significant differences between case and control group for PRDM16 (rs2651899) at genotypic level (p < 0.001), allelic level (p < 0.001; OR 3.088; 95% CI 2.082–4.579) and for dominant model (p < 0.001; OR 5.437; 95% CI 3.112–9.498). The major findings of this study suggested that PRDM16 rs2651899 is strongly associated with migraine in overall and subgroup analysis of genotypes. LRP1 (rs11172113) showed significant association with migraine except in subgroup comparison. A similar trend of association was found for TRPM8 (rs10166942) however, significant association was found only at the allelic level but no significant difference was seen at the genotypic level between case and control. One novel mutation c.67 + 4436_67 + 4438delA was also identified in the current study near LRP1 (rs11172113) polymorphic site.ConclusionIn this first-ever replication report from Pakistan, PRDM16 (rs2651899) was found as a potential genetic marker in migraine susceptibility while LRP1 (rs11172113) and TRPM8 (rs10166942) showed partial association in subgroup analysis.     

Recognition of the Thomsen-Friedenreich Pancarcinoma Carbohydrate Antigen by a Lamprey Variable Lymphocyte Receptor

Variable lymphocyte receptors (VLRs) are leucine-rich repeat proteins that mediate adaptive immunity in jawless vertebrates. VLRs were recently shown to recognize glycans, such as the tumor-associated Thomsen-Friedenreich antigen (TFα; Galβ1–3GalNAcα), with a selectivity rivaling or exceeding that of lectins and antibodies. To understand the basis for TFα recognition by one such VLR (VLRB.aGPA.23), we measured thermodynamic parameters for the binding interaction and determined the structure of the VLRB.aGPA.23-TFα complex to 2.2 Å resolution. In the structure, four tryptophan residues form a tight hydrophobic cage encasing the TFα disaccharide that completely excludes buried water molecules. This cage together with hydrogen bonding of sugar hydroxyls to polar side chains explains the exquisite selectivity of VLRB.aGPA.23. The topology of the glycan-binding site of VLRB.aGPA.23 differs markedly from those of lectins or antibodies, which typically consist of long, convex grooves for accommodating the oligosaccharide. Instead, the TFα disaccharide is sandwiched between a variable loop and the concave surface of the VLR formed by the β-strands of the leucine-rich repeat modules. Longer oligosaccharides are predicted to extend perpendicularly across the β-strands, requiring them to bend to match the concavity of the VLR solenoid.     

Characterization of a salt resistant bacterial strain <Emphasis Type="Italic">Proteus</Emphasis> sp. NA6 capable of decolorizing reactive dyes in presence of multi-metal stress

Microbial biotechnologies for the decolorization of textile wastewaters have attracted worldwide attention because of their economic suitability and easiness in handling. However, the presence of high amounts of salts and metal ions in textile wastewaters adversely affects the decolorization efficiency of the microbial bioresources. In this regard, the present study was conducted to isolate salt tolerant bacterial strains which might have the potential to decolorize azo dyes even in the presence of multi-metal ion mixtures. Out of the tested 48 bacteria that were isolated from an effluent drain, the strain NA6 was found relatively more efficient in decolorizing the reactive yellow-2 (RY2) dye in the presence of 50 g L^?1 NaCl. Based on the similarity of its 16S rRNA gene sequence and its position in a phylogenetic tree, this strain was designated as Proteus sp. NA6. The strain NA6 showed efficient decolorization (>90 %) of RY2 at pH 7.5 in the presence of 50 g L^?1 NaCl under static incubation at 30 °C. This strain also had the potential to efficiently decolorize other structurally related azo dyes in the presence of 50 g L^?1 NaCl. Moreover, Proteus sp. NA6 was found to resist the presence of different metal ions (Co⁺², Cr⁺⁶, Zn⁺², Pb⁺², Cu⁺², Cd⁺²) and was capable of decolorizing reactive dyes in the presence of different levels of the mixtures of these metal ions along with 50 g L^?1 NaCl. Based on the findings of this study, it can be suggested that Proteus sp. NA6 might serve as a potential bioresource for the biotechnologies involving bioremediation of textile wastewaters containing the metal ions and salts.     

An Efficient Rice Transformation System Utilizing Mature Seed-derived Explants and a Portable,Inexpensive Particle Bombardment Device

We developed a practical and efficient gene transfer system for indica rice utilizing mature-seed derived explants and a simple bombardment device which uses compressed helium for accelerating DNA-coated metal particles. Unlike instruments which have been described in the literature previously, this new bombardment device, which is an improvement of the particle inflow concept, does not require vacuum. This attribute simplifies the transformation procedure significantly and it makes rice transformation technology accessible to laboratories which may not have the resources to invest in more expensive particle bombardment instruments. We determined experimentally that we could recover transgenic rice plants utilizing three different particle bombardment instruments at comparable frequencies.