PO-284 Aerobic Exercise Preconditioning Prevents Behavioral Deficits in an Ovariectomized Rat Model of Post-traumatic Stress Disorder

Objective Post-traumatic Stress Disorder (PTSD) occurs in people who suffers reparative shocking, scary, or dangerous event. Evidences demonstrate that PTSD is associated with cognitive decline and depression. In the general population, women tend to show higher incidence of PTSD compared with men. Using the the ovariectomized rat model, the present work was designed to investigate the potential beneficial effect of aerobic exercise on the prevention of PTSD. Methods Adult Sprague-Dawley male rats were randomly divided into the following four groups (n = 8-10 in each group): 1) naïve control group; 2) ovariectomized group (OVX), 3) OVX with PTSD group (OVX + PTSD), 4) OVX + exercise group (OVX + Exe), and 5) OVX + PTSD + exercise (OVX + PTSD + Exe). For exercise pretreatment groups, the rats were subjected to 30 min of treadmill exercise (30 min/day, 5 days / week) for continuous 4 weeks. Open field test and elevated plus maze were used to measure behavioral changes from day 59 to day 66. Hippocampal levels of 17β-estradiol (E2) and brain-derived neurotrophic factor (BDNF) level were measured. Results 1. Results of open field and elevated plus maze test revealed that OVX animals exposed to PTSD showed obvious anxiety-like behavior compared to OVX animals without exercise. Intriguingly, anxiety-like behavior in OVX + PTSD group was significantly improved by aerobic exercise pretreatment in ovariectomized animals after PTSD. 2. Hippocampal levels of E2 and BDNF levels in the OVX + Exe group were significantly increased after aerobic exercise compared to these from OVX without exercise group. Conclusions These findings demonstrated that aerobic exercise preconditioning can efficiently prevent anxiety-like behavior in the ovariectomized rats subjected to PTSD, a mechanism could be associate with the increased levels of E2 and BDNF induced by exercise treatment

Genetic improvement of resistance to blast and bacterial blight of the elite maintainer line Rongfeng B in hybrid rice (Oryza sativa L.) by using marker-assisted selection

Rice blast caused by the fungus Magnaporthe grisea and bacterial blight (BB) caused by Xanthomonas oryzae pv. Oryzae (Xoo) are two major rice diseases in the world. An elite, early maturing maintainer line of hybrid rice, Rongfeng B hybrid rice is susceptible to both blast and BB. For improving its diseases resistance, BL122 and CBB23 were used as the donors of blast resistance genes Pi1 and Pi2 and BB resistance gene Xa23, respectively. These resistant genes were introgressed into Rongfeng B by using a marker-assisted backcross breeding programs, and two improved lines D521 and D524 with Pi1, Pi2 and Xa23 were developed. The results indicated that both improved lines showed high resistance to leaf and neck blast and BB. The resistance frequencies for the rice blast and the length of lesions resulting from BB ranged from 96.7 to 100% and 0.77 to 1.18 cm, respectively. The two improved lines showed the desired variation in the majority of evaluated agronomic traits, including the number of grains per panicle, the grains weight, plant height, and seed setting rate. A new cytoplasmic male sterile line, Rongfeng 3A, with Pi1, Pi2, and Xa23, was successfully developed through successive backcross breeding.Keywords: Gene pyramiding, marker-assisted backcross breeding, rice blast, bacterial bligh

(NZ)CH...O Contacts assist crystallization of a ParB-like nuclease

BACKGROUND: The major bottleneck for determination of 3 D structures of proteins using X-rays is the production of diffraction quality crystals. Often proteins are subjected to chemical modification to improve the chances of crystallization RESULTS: Here, we report the successful crystallization of a nuclease employing a reductive methylation protocol. The key to crystallization was the successful introduction of 44 new cohesive (NZ) CH...O contacts (3.2 – 3.7 Å) by the addition of 2 methyl groups to the side chain amine nitrogen (NZ) of 9 lysine residues of the nuclease. The new contacts dramatically altered the crystallization properties of the protein, resulting in crystals that diffracted to 1.2 Å resolution. Analytical ultracentrifugation analysis and thermodynamics results revealed a more compact protein structure with better solvent exclusion of buried Trp residues in the folded state of the methylated protein, assisting crystallization. CONCLUSION: In this study, introduction of novel cohesive (NZ)CH...O contacts by reductive methylation resulted in the crystallization of a protein that had previously resisted crystallization in spite of extensive purification and crystallization space screening. Introduction of (NZ)CH...O contacts could provide a solution to crystallization problems for a broad range of protein targets

Structural View of a Non Pfam Singleton and Crystal Packing Analysis

Comparative genomic analysis has revealed that in each genome a large number of open reading frames have no homologues in other species. Such singleton genes have attracted the attention of biochemists and structural biologists as a potential untapped source of new folds. Cthe_2751 is a 15.8 kDa singleton from an anaerobic, hyperthermophile Clostridium thermocellum. To gain insights into the architecture of the protein and obtain clues about its function, we decided to solve the structure of Cthe_2751.The protein crystallized in 4 different space groups that diffracted X-rays to 2.37 Å (P3(1)21), 2.17 Å (P2(1)2(1)2(1)), 3.01 Å (P4(1)22), and 2.03 Å (C222(1)) resolution, respectively. Crystal packing analysis revealed that the 3-D packing of Cthe_2751 dimers in P4(1)22 and C222(1) is similar with only a rotational difference of 2.69° around the C axes. A new method developed to quantify the differences in packing of dimers in crystals from different space groups corroborated the findings of crystal packing analysis. Cthe_2751 is an all α-helical protein with a central hydrophobic core providing thermal stability via π:cation and π: π interactions. A ProFunc analysis retrieved a very low match with a splicing endonuclease, suggesting a role for the protein in the processing of nucleic acids.Non-Pfam singleton Cthe_2751 folds into a known all α-helical fold. The structure has increased sequence coverage of non-Pfam proteins such that more protein sequences can be amenable to modelling. Our work on crystal packing analysis provides a new method to analyze dimers of the protein crystallized in different space groups. The utility of such an analysis can be expanded to oligomeric structures of other proteins, especially receptors and signaling molecules, many of which are known to function as oligomers

Construction of a map-based reference genome sequence for barley, Hordeum vulgare L.

Barley (Hordeum vulgare L.) is a cereal grass mainly used as animal fodder and raw material for the malting industry. The map-based reference genome sequence of barley cv. `Morex' was constructed by the International Barley Genome Sequencing Consortium (IBSC) using hierarchical shotgun sequencing. Here, we report the experimental and computational procedures to (i) sequence and assemble more than 80,000 bacterial artificial chromosome (BAC) clones along the minimum tiling path of a genome-wide physical map, (ii) find and validate overlaps between adjacent BACs, (iii) construct 4,265 non-redundant sequence scaffolds representing clusters of overlapping BACs, and (iv) order and orient these BAC clusters along the seven barley chromosomes using positional information provided by dense genetic maps, an optical map and chromosome conformation capture sequencing (Hi-C). Integrative access to these sequence and mapping resources is provided by the barley genome explorer (BARLEX).Peer reviewe

A chromosome conformation capture ordered sequence of the barley genome

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A homogeneous magnetic bead-based impedance immunosensor for highly sensitive detection of Escherichia coli O157:H7

As foodborne pathogen contamination has become a threat to human health worldwide, early detection of pathogen is significant. Traditional electrochemical immunosensors for pathogen detection involve electrode modification or samples adsorption on the electrode which affect the detection sensitivity and electrode reproducibility, thereby limiting their further application in POCT (point of care testing). We established a homogeneous magnetic bead-based electrochemical impedance system using interdigitated gold electrodes as sensing elements for high sensitivity detection of Escherichia coli. (E. coli) O157:H7. The system avoided electrode modification and sample matrix adsorption, and greatly improved detection sensitivity. The detection limit of this method for E.coli O157:H7 was 10(2) colony-forming units per milliliter (CFU mL(-1)), coefficient of variation (CV) &lt; 10 % (n = 3), which was three orders of magnitude lower than the traditional ELISA method, and the linearity detection range was 10(2) CFU mL(-1) to 10(6) CFU mL(-1). This magnetic bead-based impedance method is expected to be used for a wider range of pathogen targets analysis.</p

Controlling surface microstructure of calcium phosphate ceramic from random to custom-design

Calcium phosphate ceramics have long been studied as bone graft substitutes due to their similarity with the mineral constitute of bone and teeth, excellent biocompatibility and bioactivity. Chemical composition, macrostructure and surface microstructure are believed to be important for the bone formation within calcium phosphate ceramics. Surface microstructure has shown its crucial role in the osteogenic response of calcium phosphate ceramics; however the presence of surface irregularities and random distribution of surface microstructure in traditional calcium phosphate ceramics make it difficult to explain how surface microstructure play its role in bone formation. In the present study, we evaluated the influence of various starting apatites and sintering temperatures on the surface microstructure of the resulting hydroxyapatite ceramics. In order to minimize the randomness of the surface microstructure, laser ablation was used to generate custom-designed surface microstructures. The resulting hydroxyapatite ceramics with controlled surface microstructures would be helpful to study the role of surface microstructure on bone formation and may provide useful information for further optimization of calcium phosphate ceramics for bone regeneratio