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The Glucose 6-phosphatase (G6Pase) catalytic subunit (G6PC) catalyzes glucose 6-phosphate (G6P) to inorganic phosphate and glucose, playing a critical role in endogenous energy supply. Here, the G6PC gene family was investigated and characterized in common carp (Cyprinus carpio).

In this work, TiO2 nanoparticle (NP) compacts were employed as novel supportive substrates for synthesis of TiO2 nanowires (NWs) with controlled diameter via an alkali hydrothermal route. SEM observations showed that the alkali hydrothermal treatment caused an in situ conversion of TiO2 NPs on the outer surface of the compacts to TiO2 NWs. The diameter of each individual NW could be facilely tailored from 10 nm to 500 nm through adjustment of the hydrothermal temperature and reaction time. Moreover, compared with TiO2 NWs grown on the conventional Ti metals, those grown on the compacts were much more stable in the aqueous solution. In vitro biocompatible evaluation indicates that the as-synthesised TiO2 NWs supported attachment and proliferation of fibroblasts L929 cells, indicating a good biocompatibility. Moreover, TiO2 NWs with small diameter significantly enhanced cell attachment and proliferation. Thus, the as-synthesised TiO2 NWs might have a potential as novel biocompatible tissue regenerative matrix. [ABSTRACT FROM AUTHOR]

Abstract Background Yeast Saccharomyces cerevisiae is a widely-used system for protein expression. We previously showed that heat-killed whole recombinant yeast vaccine expressing mammalian myostatin can modulate myostatin function in mice, resulting in increase of body weight and muscle composition in these animals. Foreign DNA introduced into yeast cells can be lost soon unless cells are continuously cultured in selection media, which usually contain antibiotics. For cost and safety concerns, it is essential to optimize conditions to produce quality food and pharmaceutical products. Results We developed a simple but effective method to engineer a yeast strain stably expressing mammalian myostatin. This method utilized high-copy-number integration of myostatin gene into the ribosomal DNA of Saccharomyces cerevisiae. In the final step, antibiotic selection marker was removed using the Cre-LoxP system to minimize any possible side-effects for animals. The resulting yeast strain can be maintained in rich culture media and stably express mammalian myostatin for two years. Oral administration of the recombinant yeast was able to induce immune response to myostatin and modulated the body weight of mice. Conclusions Establishment of such yeast strain is a step further toward transformation of yeast cells into edible vaccine to improve meat production in farm animals and treat human muscle-wasting diseases in the future.

Sympatric speciation remains a central focus of evolutionary biology. Although some evidence shows speciation occurring in this way, little is known about the gene expression evolution and the characteristics of population genetics as species diverge. Two closely related Gymnocypris fish (Gymnocypris chui and Gymnocypris scleracanthus), which come from a small glacier lake in the Tibetan Plateau, Lake Langcuo, exist a possible incipient sympatric adaptive ecological speciation. We generated large amounts of RNA-Seq data from multiple individuals and tissues from each of the two species and compared gene expression patterns and genetic polymorphisms between them. Ordination analysis separated samples by organ rather than by species. The degree of expression difference between organs within and between species was different. Phylogenetic analyses indicated that the two closely related taxa formed a monophyletic complex. Population structure analysis displayed two distinctly divergent clusters of G. chui and G. scleracanthus populations. By contrast, G. scleracanthus population genetic diversity is higher than that of G. chui. Considerable sites of the two populations were differentiated with a coefficient of F ST = 0.25–0.50, implying that a small proportion of loci nevertheless exhibited deep divergence in two comparisons. Concomitantly, putatively selected genes during speciation revealed functional categories are enriched in bone morphogenesis, cell growth, neurogenetics, enzyme activity, and binding activity in G. chui population. In contrast, nutrition and localization were highlighted in G. scleracanthus. Collectively, morphological traits and dietary preference combine with genetic variation and expression variation, probably contributed to the incipient speciation of two sympatric populations. [ABSTRACT FROM AUTHOR]

We evaluated the phylogeography and historical demography of the cyprinid fish Gymnodiptychus dybowskii (subfamily Schizothoracinae) across three northern Qinghai-Tibetan Plateau ( QTP) river systems in the Tien Shan range: the Kaidu River, Ili River and Junggar Basin. Results from both mt DNA (16S rRNA and Cyt b) and nu DNA ( RAG-2) resolved three reciprocally monophyletic clades, one in each of the three river basins. Estimated divergence times ( highest posterior density (HPD) 2.4-3.7 Mya) are consistent with the hypothesis that these three clades are products of vicariance resulting from the intensive uplift of QTP and Tien Shan, and resulting expansion of the Taklimakan and Gurbantunggut deserts. Several lines of evidence indicate dynamic demographic histories for the three clades, with late Quaternary population bottlenecks and expansions in the Kaidu and Ili rivers and, possibly, a Holocene decline in the Junggar Basin. For conservation purposes, the three clades should be treated as species or minimally, as evolutionarily significant units (ESUs). They have experienced decades of anthropogenic disturbance and preservation of the three species/ ESUs will require more sustainable management of the aquatic resources. [ABSTRACT FROM AUTHOR]

Local adaptation towards divergent ecological conditions often results in genetic differentiation and adaptive phenotypic divergence. To illuminate the ecological distinctiveness of the schizothoracine fish, we studied a Gymnocypris species complex consisting of three morphs distributed across four bodies of water (the Yellow River, Lake Qinghai, the Ganzi River and Lake Keluke) in the Northeast Tibetan Plateau. We used a combination of mitochondrial (16S rRNA and Cyt b) and nuclear (RAG-2) genetic sequences to investigate the phylogeography of these morphs based on a sample of 277 specimens. Analysis of gill rakers allowed for mapping of phenotypic trajectories along the phylogeny. The phylogenetic and morphological analyses showed that the three sparsely rakered morphs were present at two extremes of the phylogenetic tree: the Yellow River morphs were located at the basal phylogenetic split, and the Lake Keluke and Ganzi River morphs at the peak, with the densely rakered Lake Qinghai morphs located between these two extremes. Age estimation further indicated that the sparsely rakered morphs constituted the oldest and youngest lineages, whereas the densely rakered morph was assigned to an intermediate-age lineage. These results are most compatible with the process of evolutionary convergence or reversal. Disruptive natural selection due to divergent habitats and dietary preferences is likely the driving force behind the formation of new morphs, and the similarities between their phenotypes may be attributable to the similarities between their forms of niche tracking associated with food acquisition. This study provides the first genetic evidence for the occurrence of convergence or reversal in the schizothoracine fish of the Tibetan Plateau at small temporal scales. [ABSTRACT FROM AUTHOR]

Using engineered nucleases such as zinc-finger nucleases (ZFNs) and TALE nuclease (TALEN) to accomplish genome editing often causes high cellular toxicity because of the consistent expression of artificial nucleases and off-targeting effect. And lacking selection marker in modified cells makes it hard to enrich these positive cells. Here we introduce a method by incorporating a surrogate reporter enrichment into a suicidal ZFN system, which is designed by a pair of ZFN expression cassettes flanked with its target sites. Our data demonstrated that this modified system achieved almost the same ZFN activity as the original method but reduced ~40% toxicity. This new suicidal ZFN expression system coupled with a surrogate reporter not only enables decreased cellular toxicity but also makes the genetic modified cells to be enriched by EGFP analysis.

The cDNA of cattle Ghrelin gene was amplified from abomasum fundic gland mRNA of Qinchuan Cattle by RT-PCR. PCR product was cloned into the T vector pGM-T to construct pGh-T1 for sequencing. Then the cDNA was subcloned into the prokaryotic expressing plasmid vector pET32a (+) and transformed into host Escherichia coli strain BL21 (DE3) for expression. The expression of pGh-32 mature Ghrelin protein was induced by IPTG and was identified by SDS-PAGE. The expression product was observed with soluble protein and inclusion body. Western blotting showed that the recombinant protein was recognized by his-antibody specifically. The protein was purified by Ni-NTA column and was used to inject rabbits to obtain polyclona antibody. ELISA result showed that the antibody titer was 1:12 800. The immunohistochemistry test between the hypothalamus arcuate nucleus and the antibody showed that fusion protein had biological activity. This will provide a basis for further study on the biological function of Ghrelin protein to growth and development and fat deposition of cattle.