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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2009.11.034 Byline: Qiuxia Guo, Kairong Li, N. Abimbola Sunmonu, James Y.H. Li Keywords: Fgf8; Alternative Splicing; Midbrain; Cerebellum; Organizer; Signaling Abstract: The single Fgf8 gene in mice produces eight protein isoforms (Fgf8a-h) with different N-termini by alternative splicing. Gain-of-function studies have demonstrated that Fgf8a and Fgf8b have distinct activities in the developing midbrain and hindbrain (MHB) due to their different binding affinities with FGF receptors. Here we have performed loss-of-function analyses to determine the in vivo requirement for these two Fgf8 spliceforms during MHB development. We showed that deletion of Fgf8b-containing spliceforms (b, d, f and h) leads to loss of multiple key regulatory genes, including Fgf8 itself, in the MHB region. Therefore, specific inactivation of Fgf8b-containing spliceforms, similar to the loss of Fgf8, in MHB progenitors results in deletion of the midbrain, isthmus, and cerebellum. We also created a splice-site mutation abolishing Fgf8a-containing spliceforms (a, c, e, and g). Mice lacking Fgf8a-containing spliceforms exhibit growth retardation and postnatal lethality, and the phenotype is variable in different genetic backgrounds, suggesting that the Fgf8a-containing spliceforms may play a role in modulating the activity of Fgf8. Surprisingly, no discernable defect was detected in the midbrain and cerebellum of Fgf8a-deficient mice. To determine if Fgf17, which is expressed in the MHB region and possesses similar activities to Fgf8a based on gain-of-function studies, may compensate for the loss of Fgf8a, we generated Fgf17 and Fgf8a double mutant mice. Mice lacking both Fgf8a-containing spliceforms and Fgf17 display the same defect in the posterior midbrain and anterior cerebellum as Fgf17 mutant mice. Therefore, Fgf8b-containing spliceforms, but not Fgf8a, are essential for the function of Fgf8 during the development of the midbrain and cerebellum. Author Affiliation: Department of Genetics and Developmental Biology, University of Connecticut Health Center, Farmington, CT 06030, USA Article History: Received 23 October 2009; Revised 23 November 2009; Accepted 30 November 2009

Abstract: Dam, not only has great ability to alleviate water shortages especially during the dry season which improve hydropower capacity, but also plays an imporant rule in the river ecosystem. Dam has significant effect in improving our water environment and protecting ecological system.This paper copes with the three-dimensional model of dams and discusses OpenGL modeling, lighting, material, model transformation, perspective transformation technologies to achieve visualization of the dam, and eventually we visualize the dam through concrete examples. [Copyright &y& Elsevier]

Abstract: For a pump station supplying water, this paper is analyzing the real situation of the station considering all the real existing factors related to set a mathematic model, in the goal of reducing the cost thru adjusting the water flow in different time sections. The dynamic programming model method with detailed analyses is induced illustrated by an example of optimizing the cost of a single unit in a single day with a fixed water-supply amount in the paper. More interesting, a special case of this model is illustrated to proof that non-stop pump working is more power saving than intermittent working given the unchangeable electricity price. [Copyright &y& Elsevier]

Abstract: Palladium-modified TiO2 nanofibers (Pd/TiO2NFs) were prepared from PdCl2 and titanate nanotubes by a photodecomposition method. The samples were characterized with X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and UV–Vis spectra. The morphology of the nanotubes was destroyed during the illumination process due to the high activity of titanate nanotubes and the existence of Pd/TiO2 batteries. The photocatalytic activity of the samples for degradation of methyl orange solution was also studied, and high photocatalytic activity was observed. When palladium content was 1.5wt.%, Pd/TiO2NFs showed the highest activity. [Copyright &y& Elsevier]

Abstract GATA transcription factors (GATAs) are widely expressed among various organisms and belong to the zinc finger protein family. GATA transcription factors play important roles in the proliferation, differentiation, and development of eukaryotes. Previous studies have shown that GATA participates in oogenesis by selective splicing in silkworms. In this study, we investigated the function of GATAs during vitellogenesis using female silkworms (Bombyx mori). Six types of GATA transcription factors were successfully cloned in the fat body of silkworms during the wandering stage and only BmGATAβ4 induced the activity of the Bombyx mori vitellogenin (BmVg) promoter. Furthermore, BmVg and BmGATAβ4 exhibited similar expression patterns in the fat body of female silkworms during the wandering stage. Electrophoretic mobility shift assays, cell transfection assays, and chromatin immunoprecipitation showed that BmGATAβ4 was involved in regulating the transcription of BmVg by directly binding to the GATA cis -response element 1 (CRE1) and GATA cis -response element 2 (CRE2) in the promoter of the BmVg gene. RNA interference of BmGATAβ4 in female silkworms downregulated BmVg transcription, resulting in a decrease in egg size and shortening of the length of egg tubes relative to the control. In summary, our results indicated that BmGATAβ4 bound to the GATA CRE1 and CRE2 motifs in the BmVg promoter to upregulate BmVg expression in the fat body of female silkworms. Graphical abstract Image 1 Highlights • BmGATAβ4 induces the activity of the vitellogenin (BmVg) promoter. • BmGATAβ4 regulates BmVg transcription by directly binding to GATA CRE1 and CRE2 DNA elements. • BmVg and BmGATAβ4 exhibit similar expression profiles in the fat body of female silkworms. • BmGATAβ4 knockdown affects reproduction in female silkworms. [ABSTRACT FROM AUTHOR]

• Amino acid content increases upon knockout of Fib-H. • The majority of the main amino acids of silk protein could induce BmVg expression. • Amino acid induces BmVg expression through the TOR signalling pathway. • AA injection induces BmVg up-regulation after finishing spinning. Silkworms are economically important insects because of the value of their silk. After finishing silk spinning, silkworms begin another important physiological process, vitellogenesis. In this study, we explored the relationship between silk spinning and vitellogenin (BmVg) expression in silkworms. In silkworms with the silk fibroin heavy chain gene knocked-out, the concentration of amino acids in the hemolymph was found to be significantly higher than that in the wild type, and the expression of BmVg was advanced at day 7 of the fifth instar stage and 0 h after spinning. Furthermore, through culturing fat body in vitro with different substances treatment including glucose, trehalose, amino acids, 20-hydroxyecdysone, and insulin, we found that only amino acids could induce BmVg expression. RNA interference of BmTOR1 in female silkworms could down-regulate BmVg transcription, resulting in shortened egg ducts and smaller eggs relative to the control. Therefore, these results showed that amino acids could induce BmVg expression through the TOR signaling pathway. Fat body cultured with amino acids in vitro and experiments involving amino acids injected into the silkworm showed that the majority of main amino acids of silk protein could induce BmVg expression. These results suggested that BmVg expression is related to silk spinning and this study would lay a foundation for elucidating the stage specificity expression of BmVg. [ABSTRACT FROM AUTHOR]