Phylogeny of the genus Morus (Urticales: Moraceae) inferred from ITS and trnL-F sequences

Both nuclear ribosomal ITS and chloroplast trnL-F sequences were acquired from 13 mulberry genotypes belonging to nine species and three varieties, and one paper mulberry. The later belongs to genus B. papyrifera, designed as outgroup, and were analyzed. Within the genus Morus, the sequence diversity of ITS was much higher than that of trnL-F. The results of phylogenetic analyses based on these data (separately or combined) show that the genus Morus is monophyletic group. Strict consensus tree obtained through the Neighbor-joining method can be divided into five major clades in the genus Morus, according to combined sequence data. M. bombycis, M. alba var. venose formed clades A and B, respectively. Clade C comprises of 5 species; M. rotundiloba, M. atropurpurea, M. mongolica, M. australi, and M. mongolica var. diabolica. Clade D comprises of 3 species; M. wittiorum, M. laevigata, and M. alba. Clade E comprises of 2 species; M. multicaulis, and M.alba var. macrophylla. The results from cluster analysis were basically in agreement with the existing morphologic classification.African Journal of Biotechnology Vol. 4 (6), pp. 563-569, 200

Genetic transformation of cotton with a harpin-encoding gene hpaXoo confers an enhanced defense response against different pathogens through a priming mechanism

<p>Abstract</p> <p>Background</p> <p>The soil-borne fungal pathogen <it>Verticillium dahliae </it>Kleb causes <it>Verticillium </it>wilt in a wide range of crops including cotton (<it>Gossypium hirsutum</it>). To date, most upland cotton varieties are susceptible to <it>V. dahliae </it>and the breeding for cotton varieties with the resistance to <it>Verticillium </it>wilt has not been successful.</p> <p>Results</p> <p>Hpa1_Xoois a harpin protein from <it>Xanthomonas oryzae </it>pv. <it>oryzae </it>which induces the hypersensitive cell death in plants. When <it>hpa1</it>_{<it>Xoo </it>}was transformed into the susceptible cotton line Z35 through <it>Agrobacterium</it>-mediated transformation, the transgenic cotton line (T-34) with an improved resistance to <it>Verticillium dahliae </it>was obtained. Cells of the transgenic T-34, when mixed with the conidia suspension of <it>V. dahliae</it>, had a higher tolerance to <it>V. dahliae </it>compared to cells of untransformed Z35. Cells of T-34 were more viable 12 h after mixing with <it>V. dahliae </it>conidia suspension. Immunocytological analysis showed that Hpa1_Xoo, expressed in T-34, accumulated as clustered particles along the cell walls of T-34. In response to the infection caused by <it>V. dahliae</it>, the microscopic cell death and the generation of reactive oxygen intermediates were observed in leaves of T-34 and these responses were absent in leaves of Z35 inoculated with <it>V. dahliae</it>. Quantitative RT-PCR analysis indicated that five defense-related genes, <it>ghAOX1, hin1, npr1, ghdhg-OMT</it>, and <it>hsr203J</it>, were up-regulated in T-34 inoculated with <it>V. dahliae</it>. The up-regulations of these defense-relate genes were not observed or in a less extent in leaves of Z-35 after the inoculation.</p> <p>Conclusions</p> <p>Hpa1_Xooaccumulates along the cell walls of the transgenic T-34, where it triggers the generation of H₂O₂as an endogenous elicitor. T-34 is thus in a primed state, ready to protect the host from the pathogen. The results of this study suggest that the transformation of cotton with <it>hpa1</it>_{<it>Xoo </it>}could be an effective approach for the development of cotton varieties with the improved resistance against soil-borne pathogens.</p

Suspension polymerization casting of lead zirconate titanate, part I: Acrylamide hydrogel system

Suspension polymerization casting of lead zirconate titanate (PZT) filled acrylamide systems was studied. A high solid loading (51 vol%) PZT slurry with low viscosity (about 280 mPa·s at shear rate 10 s −1 ) was obtained by optimizing the dispersant amount. The polymerization process for the monomer solution and PZT slurry were characterized with the help of the storage modulus measurement. For the monomer solution, the overall activation energy of gelation was calculated as 60–76 kJ/mol, while for the PZT slurry, this energy increased to 91 ± 9 kJ/mol. The drying, burnout and sintering processes were also addressed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44771/1/10853_2004_Article_5141969.pd

Transcriptomic and Proteomic Analysis of Shaan2A Cytoplasmic Male Sterility and Its Maintainer Line in Brassica napus

Cytoplasmic male sterility (CMS) lines are widely used for hybrid production in Brassica napus. The Shaan2A CMS system is one of the most important in China and has been used for decades; however, the male sterility mechanism underlying Shaan2A CMS remains unknown. Here, we performed transcriptomic and proteomic analysis, combined with additional morphological observation, in the Shaan2A CMS. Sporogenous cells, endothecium, middle layer, and tapetum could not be clearly distinguished in Shaan2A anthers. Furthermore, Shaan2A anther chloroplasts contained fewer starch grains than those in Shaan2B (a near-isogenic line of Shaan2A), and the lamella structure of chloroplasts in Shaan2A anther wall cells was obviously aberrant. Transcriptomic analysis revealed differentially expressed genes (DEGs) mainly related to carbon metabolism, lipid and flavonoid metabolism, and the mitochondrial electron transport/ATP synthesis pathway. Proteomic results showed that differentially expressed proteins were mainly associated with carbohydrate metabolism, energy metabolism, and genetic information processing pathways. Importantly, nine gene ontology categories associated with anther and pollen development were enriched among down-regulated DEGs at the young bud (YB) stage, including microsporogenesis, sporopollenin biosynthetic process, and tapetal layer development. Additionally, 464 down-regulated transcription factor (TF) genes were identified at the YB stage, including some related to early anther differentiation such as SPOROCYTELESS (SPL, also named NOZZLE, NZZ), DYSFUNCTIONAL TAPETUM 1 (DYT1), MYB80 (formerly named MYB103), and ABORTED MICROSPORES (AMS). These results suggested that the sterility gene in the Shaan2A mitochondrion might suppress expression of these TF genes in the nucleus, affecting early anther development. Finally, we constructed an interaction network of candidate proteins based on integrative analysis. The present study provides new insights into the molecular mechanism of Shaan2A CMS in B. napus

Powdery Mildews Are Characterized by Contracted Carbohydrate Metabolism and Diverse Effectors to Adapt to Obligate Biotrophic Lifestyle

Powdery mildew is a widespread plant disease caused by obligate biotrophic fungal pathogens involving species-specific interactions between host and parasite. To gain genomic insights into the underlying obligate biotrophic mechanisms, we analyzed 15 microbial genomes covering powdery and downy mildews and rusts. We observed a genome-wide, massive contraction of multiple gene families in powdery mildews, such as enzymes in the carbohydrate metabolism pathway, when compared with ascomycete phytopathogens, while the fatty acid metabolism pathway maintained its integrity. We also observed significant differences in candidate secreted effector protein (CSEP) families between monocot and dicot powdery mildews, perhaps due to different selection forces. While CSEPs in monocot mildews are likely subject to positive selection causing rapid expansion, CSEP families in dicot mildews are shrinking under strong purifying selection. Our results not only illustrate obligate biotrophic mechanisms of powdery mildews driven by gene family evolution in nutrient metabolism, but also demonstrate how the divergence of CSEPs between monocot and dicot lineages might contribute to species-specific adaption

Fabrication and experimental characterization of d31 telescopic piezoelectric actuators

A popular and useful piezoelectric actuator is the stack. Unfortunately with this type of actuation architecture the long lengths normally required to obtain necessary displacements can pose packaging and buckling problems. To overcome these limitations, a new architecture for piezoelectric actuators has been developed called telescopic. The basic design consists of concentric shells interconnected by end-caps which alternate in placement between the two axial ends of the shells. This leads to a linear displacement amplification at the cost of force; yet the force remains at the same magnitude as a stack and significantly higher than bender type architectures. This paper describes the fabrication and experimental characterization of three different telescopic prototypes. The actuator prototypes discussed in this paper mark a definitive step forward in fabrication techniques for complex piezoceramic structures. Materials Systems, Inc. has adapted injection molding for the fabrication of net shape piezoceramic actuators. Injection molding provides several advantages over conventional fabrication techniques, including: high production rate, uniform part dimensions, uniform piezoelectric properties, and reduced fabrication and assembly costs. Acrylate polymerization, developed at the University of Michigan, is similar to gelcasting, but uses a nonaqueous slurry which facilitates the production of large, tall, complex components such as the telescopic actuator, and is ideal for the rapid manufacture of unique or small batch structures. To demonstrate these fabrication processes a five tube telescopic actuator was injection molded along with a very tall three tube actuator that was cast using the acrylate polymerization method. As a benchmark, a third actuator was built from off-the-shelf tubes that were joined with aluminum end-caps. Each prototype's free deflection behavior was experimentally characterized and the results of the testing are presented within this paper.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44767/1/10853_2004_Article_382116.pd

Transcriptome analysis of Hpa1Xoo transformed cotton revealed constitutive expression of genes in multiple signalling pathways related to disease resistance

The transcriptome profile in leaves and roots of the transgenic cotton line T-34 expressing hpa1Xoo from Xanthomonas oryzae pv. oryzae was analysed using a customized 12k cotton cDNA microarray. A total of 530 cDNA transcripts involved in 34 pathways were differentially expressed in the transgenic line T-34, in which 123 differentially expressed genes were related to the cotton defence responses including the hypersensitive reaction, defence responses associated with the recognition of pathogen-derived elicitors, and defence signalling pathways mediated by salicylic acid, jasmonic acid, ethylene, auxin, abscicic acid, and Ca2+. Furthermore, transcripts encoding various leucine-rich protein kinases and mitogen-activated protein kinases were up-regulated in the transgenic line T-34 and expression of transcripts related to the energy producing and consuming pathway was also increased, which suggested that the enhanced metabolism related to the host defence response in the transgenic line T-34 imposed an increased energy demand on the transgenic plant

A Common SMAD7 Variant Is Associated with Risk of Colorectal Cancer: Evidence from a Case-Control Study and a Meta-Analysis

<div><h3>Background</h3><p>A common genetic variant, rs4939827, located in <em>SMAD7</em>, was identified by two recent genome-wide association (GWA) studies to be strongly associated with the risk of colorectal cancer (CRC). However, the following replication studies yielded conflicting results.</p> <h3>Method and Findings</h3><p>We conducted a case-control study of 641 cases and 1037 controls in a Chinese population and then performed a meta-analysis, integrating our and published data of 34313 cases and 33251 controls, to clarify the relationship between rs4939827 and CRC risk. In our case-control study, the dominant model was significant associated with increased CRC risk [Odds Ratio (OR) = 1.46; 95% confidence interval (95% CI), 1.19–1.80]. The following meta-analysis further confirmed this significant association for all genetic models but with significant between-study heterogeneity (all <em>P</em> for heterogeneity <0.1). By stratified analysis, we revealed that ethnicity, sample size, and tumor sites might constitute the source of heterogeneity. The cumulative analysis suggested that evident tendency to significant association was seen with adding study samples over time; whilst, sensitive analysis showed results before and after removal of each study were similar, indicating the highly stability of the current results.</p> <h3>Conclusion</h3><p>Results from our case-control study and the meta-analysis collectively confirmed the significant association of the variant rs4939827 with increased risk of colorectal cancer. Nevertheless, fine-mapping of the susceptibility loci defined by rs4939287 should be imposed to reveal causal variant.</p> </div