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The genome of tomato ( L.) is being sequenced by an international consortium of 10 countries (Korea, China, the United Kingdom, India, the Netherlands, France, Japan, Spain, Italy, and the United States) as part of the larger “International Solanaceae Genome Project (SOL): Systems Approach to Diversity and Adaptation” initiative. The tomato genome sequencing project uses an ordered bacterial artificial chromosome (BAC) approach to generate a high-quality tomato euchromatic genome sequence for use as a reference genome for the Solanaceae and euasterids. Sequence is deposited at GenBank and at the SOL Genomics Network (SGN). Currently, there are around 1000 BACs finished or in progress, representing more than a third of the projected euchromatic portion of the genome. An annotation effort is also underway by the International Tomato Annotation Group. The expected number of genes in the euchromatin is ∼40,000, based on an estimate from a preliminary annotation of 11% of finished sequence. Here, we present this first snapshot of the emerging tomato genome and its annotation, a short comparison with potato ( L.) sequence data, and the tools available for the researchers to exploit this new resource are also presented. In the future, whole-genome shotgun techniques will be combined with the BAC-by-BAC approach to cover the entire tomato genome. The high-quality reference euchromatic tomato sequence is expected to be near completion by 2010.

The bread-making quality of wheat is strongly influenced by multiple low molecular weight glutenin subunit (LMW-GS) proteins expressed in the seeds. However, the organization, recombination and expression of LMW-GS genes and their functional mechanism in bread-making are not well understood. Here we report a systematic molecular analysis of LMW-GS genes located at the orthologous Glu-3 loci (Glu-A3, B3 and D3) of bread wheat using complementary approaches (genome wide characterization of gene members, expression profiling, proteomic analysis). Fourteen unique LMW-GS genes were identified for Xiaoyan 54 (with superior bread-making quality). Molecular mapping and recombination analyses revealed that the three Glu-3 loci of Xiaoyan 54 harbored dissimilar numbers of LMW-GS genes and covered different genetic distances. The number of expressed LMW-GS in the seeds was higher in Xiaoyan 54 than in Jing 411 (with relatively poor bread-making quality). This correlated with the finding of higher numbers of active LMW-GS genes at the A3 and D3 loci in Xiaoyan 54. Association analysis using recombinant inbred lines suggested that positive interactions, conferred by genetic combinations of the Glu-3 locus alleles with more numerous active LMW-GS genes, were generally important for the recombinant progenies to attain high Zeleny sedimentation value (ZSV), an important indicator of bread-making quality. A higher number of active LMW-GS genes tended to lead to a more elevated ZSV, although this tendency was influenced by genetic background. This work provides substantial new insights into the genomic organization and expression of LMW-GS genes, and molecular genetic evidence suggesting that these genes contribute quantitatively to bread-making quality in hexaploid wheat. Our analysis also indicates that selection for high numbers of active LMW-GS genes can be used for improvement of bread-making quality in wheat breeding.

AtSPX3, responding to phosphate (Pi) deficiency by its expression, is an important gene involved in Pi homeostasis in Arabidopsis. To understand its transcriptional regulation, we characterized the AtSPX3 promoter by distal truncation, internal deletion and mutation of the predicted cis-elements, and identified multiple cis-elements responsive to Pi status. The P1BS (AtPHR-binding site) and AtMyb4 (putative MYB4-binding site) elements were two main cis-elements in the AtSPX3 promoter. P1BS is essential and has a dosage effect for activating expression of the gene under Pi deficiency, while the element AtMyb4 possesses a dual function: one is to enhance AtSPX3 expression in roots under Pi deficiency, and the other one is to repress AtSPX3 expression in shoots under both Pi deficiency and sufficiency. Moreover, we confirmed that AtPHR1, a key transcription factor in Pi homeostasis of plants, was required for the negative regulation function of the AtMyb4 element in shoots. Additionally, we also found that the AtSPX3 promoter had a length limitation for activating gene expression. Generally, our findings in this work are useful for understanding the molecular regulation mechanism of genes involved in Pi uptake and homeostasis. [ABSTRACT FROM AUTHOR]

We have fabricated the InGaN/AlGaInN multiple quantum wells with lattice-matched AlGaN/InGaN superlattices barriers (SL-MQWs). The lattice-matched superlattices promote the formation of the high-quality MQWs and eliminate the large polarization electric field. Highly excited photoluminescence measurement is performed by Ti-sapphire pulse laser with the maximal carrier density of 1020 cm-3. Under such high carrier density, the conventional InGaN/GaN MQWs (C-MQWs) have an additional nonradiative loss of carriers and suffer from the efficiency droop effect, while slight droop behavior is observed in the SL-MQWs sample. The results show that the substitution of AlGaN/InGaN superlattices as quantum barriers can effectively suppress the droop behavior at highly excited condition.

In order to realize the connection for metal foil, a longitudinal-torsional compound consolidation vibration system is proposed, and relative experiments are carried out. Firstly, the structure of longitudinal-torsional compound consolidation vibration system was designed, detailed structural design of the compound piezoelectric transducer and the compound horn in the vibration system was carried out, and torsional vibration analysis of the compound horn with spiral grooves was carried out based on mechanical principle. Secondly, modal calculation and harmonic response analysis of longitudinal-torsional compound consolidation vibration system were carried out, and corresponding vibration mode and harmonic frequency were obtained. The effect of structural parameters for the compound horn on the frequency of the consolidation vibration system was analysed, and structural parameters of the compound horn were optimized. Finally, the prototype was made, and the experimental platform was built to test the amplitude. When the frequency is near 20000 Hz, the resonance is achieved in three directions at the same time, and the resonance frequency is 19800 Hz. Through the frequency-scanning test, the maximum longitudinal amplitude of the consolidation vibration system is 16 μm, and the maximum torsional amplitudes of X and Y are 7.9 μm and 8.1 μm. The longitudinal-torsional compound consolidation vibration system can realize the connection of the same and different metal foils and has broad application prospects.

The study was performed to analyze the proteomic profiling of doxorubicin-treated H9c2 cardiomyocytes in order to identify novel protein biomarkers associated with doxorubicininduced cardiomyopathy. The protein profiling of H9c2 cells in response to doxorubicin at an apoptosis-induced concentration of 0.5 μM were compared using iTRAQ analysis. Western-blot analysis was used to confirm differentially expressed proteins identified in the proteomic study. A total of 22 differently expressed proteins were identified in doxorubicin-treated H9c2 cells including 15 up-regulated and 7 down-regulated proteins. Gene Ontology (GO) analysis revealed that 10 altered proteins were enriched in the process of apoptosis. We further validated the expression of cathepsin B and its possible regulator nuclear factor kappa B (NF-κB) in H9c2 cells were increased during doxorubicin treatment using Western-blots. Differentially expressed proteins might provide clues to clarify novel mechanisms underlying doxorubicin-induced cardiomyopathy. Our results also suggest that increased cathepsin B expression might be associated with NF-κB upregulation, and the exact mechanisms need to be clarified. [ABSTRACT FROM AUTHOR]