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The Himalayan marmot (Marmota himalayana), a natural host and transmitter of plague, is also susceptible to the hepadnavirus infection. To reveal the genetic basis of the hepadnavirus susceptibility and the immune response to plague, we systematically characterized the features of immune genes in Himalayan marmot with those of human and mouse. We found that the entire major histocompatibility complex region and the hepatitis B virus pathway genes of the Himalayan marmot were conserved with those of humans. A Trim (tripartite motif) gene cluster involved in immune response and antiviral activity displays dynamic evolution, which is reflected by the duplication of Trim5 and the absence of Trim22 and Trim34. Three key regions of Ntcp, which is critical for hepatitis B virus entry, had high identity among seven species of Marmota. Moreover, we observed a severe alveolar hemorrhage, inflammatory infiltrate in the infected lungs and livers from Himalayan marmots after infection of EV76, a live attenuated Yersinia pestis strain. Lots of immune genes were remarkably up-regulated, which several hub genes H2r[gamma], Tra29, and Nlrp7 are placed at the center of the gene network. These findings suggest that Himalayan marmot is a potential animal model for study on the hepadnavirus and plague infection. Key words: Himalayan marmot, immune system, hepadnavirus, plague. La marmotte de l'Himalaya (Marmota himalayana), un hote naturel qui peut transmettre la peste, est egalement sensible a l'infection par l'hepadnavirus. Afin de reveler l'assise genetique de la sensibilite a l'hepadnavirus et de la reponse immunitaire a la peste, les auteurs ont systematiquement caracterise les genes du systeme immunitaire chez la marmotte de l'Himalaya avec ceux chez l'humain et la souris. Les auteurs ont trouve que la region entiere du complexe majeur d'histocompatibilite et les genes du sentier du virus de l'hepatite B chez la marmotte de l'Himalaya sont conserves avec ceux presents chez l'humain. Un groupe de genes Trim (<< a motif tripartite >>) implique dans la reponse immunitaire et l'activite antivirale presentait une evolution dynamique, laquelle se reflete par la duplication de Trim5 et l'absence des genes Trim22 et Trim34. Trois regions cles de Ntcp, lequel est critique pour l'entree du virus de l'hepatite B, presentaient un fort niveau d'identite au sein de sept especes de Marmota. De plus, les auteurs ont observe une severe hemorragie alveolaire, un infiltrat inflammatoire dans les poumons et le foie chez des marmottes de l'Himalaya apres infection avec l'EV76, une souche vivante attenuee du Yersinia pestis. Plusieurs genes du systeme immunitaire etaient remarquablement plus fortement exprimes, dont plusieurs genes (H2r[gamma], Tra29 et Nlrp7) qui sont au coeur de reseaux de genes. Ces observations suggerent que la marmotte de l'Himalaya constitue une espece modele potentielle pour l'etude de l'infection avec l'hepadnavirus et la peste. [Traduit par la Redaction] Mots-cles : marmotte de l'Himalaya, systeme immunitaire, hepadnavirus, peste., Introduction The Himalayan marmot (Marmota himalayana) is a marmot species that inhabits alpine grasslands throughout the Himalayan regions and on the Tibetan Plateau (Nikol'skii and Ulka 2006; Hoffmann et al. [...]

Background: Rabbits are well-domesticated animals. As a crucial economic animal, rabbit has been successfully bred into wool-use, meat-use and fur-use breeds. Hair length is one of the most economically important traits affecting profitability in wool rabbits. In this study, to identify selection signatures with the long-hair trait, whole-genomic resequencing of long-haired rabbits (Angora rabbits) and short-haired rabbits (Rex and New Zealand rabbits) was performed. Results: By genome-wide selective sweeping analysis based on population comparison, we identified a total of 5.85 Mb regions (containing 174 candidate genes) with strong selection signals. Six of these genes (Dusp1, Ihh, Fam134a, Map3k1, Spata16, and Fgf5) were enriched in the MAPK signalling and Hedgehog signalling pathways, both of which are closely associated with hair growth regulation. Among these genes, Fgf5 encodes the FGF5 protein, which is a well-established regulator of hair growth. There was a nonsynonymous nucleotide substitution (T19234C) in the Fgf5 gene. At this locus, the C allele was present in all of the tested Angora rabbits, while the T allele was dominant in New Zealand and Rex rabbits. We further confirmed that the C allele was conserved in Angora rabbits by screening an additional 135 rabbits. Moreover, the results of functional predictions and co-immunoprecipitation revealed that the T19234C mutation impaired the binding capacity of FGF5 to its receptor FGFR1. Conclusions: We discovered that the homozygous missense mutation T19234C within Fgf5 might contribute to the long-hair trait of Angora rabbits by reducing its receptor binding capacity. This finding will provide new insights into the genetic basis underlying the genetic improvement of Angora rabbits and benefit the improvement of rabbit breeding in the future. [ABSTRACT FROM AUTHOR]

The growth and physiological process of microalgae interact with environmental nutrients. In the present study, we compared the growth and physiological characteristics of coccolithophore Chrysotila roscoffensis under the effects of phosphate at high and low concentrations, and of organic phosphorus of adenosine triphosphate (ATP) and Na2-glycerophosphate (SG). The growth, photosynthesis, calcification, alkaline phosphatase activity, and inorganic nutrient absorption rate were comparatively studied. The results showed that the culture with a low concentration of initial phosphate (6 μM) had a lower growth rate than that with a high concentration (45 μM). However, a relatively similar maximum cell density could be achieved. Equimolar inorganic phosphorus supported a higher initial growth rate than organic phosphorus. ATP was better than SG at supporting higher growth rates, higher photosynthetic activity, and higher cell density. Cellular alkaline phosphatase (AP) responded rapidly to nutrient variations with sharp changes of activities, independent of the initial P resources. Cellular calcification was at a higher level in groups with lower growth rates. Phosphate in low concentration in the medium was not absorbed during the early growth period while that in high concentration was rapidly absorbed. Instead, phosphate in low concentration was rapidly absorbed in the late stationary phase. The absorption of nitrate was affected by the initial P resources as well. The DIN/DIP ratio in the water varied significantly during the growth periods. The results indicated that C. roscoffensis had flexible physiological strategies in utilizing varied phosphorus resources, and high cell density maintenance of C. roscoffensis may play roles in nutrient conditions in the water. This study may help to extend the understanding of nutrient utilization strategy in microalgae and to apply reference in the application of Chrysotila species in the removal of nutrient pollution. [ABSTRACT FROM AUTHOR]

Arrhythmia is a common cardiovascular disease; the electrocardiogram (ECG) is widely used as an effective tool for detecting arrhythmia. However, real-time arrhythmia detection monitoring is difficult, so this study proposes a long short-term memory-residual model. Individual beats provide morphological features and combined with adjacent segments provide temporal features. Our proposed model captures the time-domain and morphological ECG signal information simultaneously and fuses the two information types. At the same time, the attention block is applied to the network to further strengthen the useful information, capture the hidden information in the ECG signal, and improve the model classification performance. Our model was finally trained and tested on the MIT-BIH arrhythmia database, and the entire dataset was divided into intrapatient and interpatient modes. Accuracies of 99.11% and 85.65%, respectively, were obtained under the two modes. Experimental results demonstrate that our proposed method is an efficient automated detection method. [ABSTRACT FROM AUTHOR]

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Rabbits (Oryctolagus cuniculus) are one of the most widely used animal models for the study of human lipid metabolism and atherosclerosis because they are more sensitive to a cholesterol diet than other experimental animals such as rodents. Currently, two hypercholesterolemic rabbit models are frequently used for atherosclerosis studies. One is a cholesterol-fed wild-type rabbit and the other is the Watanabe heritable hyperlipidemic (WHHL) rabbit, which is genetically deficient in low density lipoprotein (LDL) receptor function. Wild-type rabbits can be easily induced to develop severe hypercholesterolemia with a cholesterol-rich diet due to the marked increase in hepatically and intestinally derived remnant lipoproteins, called β-very low density lipoproteins (VLDL), which are rich in cholesteryl esters. WHHL rabbits are characterized by elevated plasma LDL levels on a standard chow diet, which resembles human familial hypercholesterolemia. Therefore, both rabbit models develop aortic and coronary atherosclerosis, but the elevated plasma cholesterol levels are caused by completely different mechanisms. In addition, cholesterol-fed rabbits but not WHHL rabbits exhibit different degrees of hepatosteatosis. Recently, we along with others have shown that there are many differentially expressed genes in the atherosclerotic lesions and livers of cholesterol-fed rabbits that are either significantly up- or down-regulated, compared with those in normal rabbits, including genes involved in the regulation of inflammation and lipid metabolism. Therefore, dietary cholesterol plays an important role not only in hypercholesterolemia and atherosclerosis but also in hepatosteatosis. In this review, we make an overview of the recent progress in genomic and transcriptomic analyses of hypercholesterolemic rabbits. These transcriptomic profiling data should provide novel insight into the relationship between hypercholesterolemia and atherosclerosis or hepatic dysfunction caused by dietary cholesterol. [ABSTRACT FROM AUTHOR]

Rabbits are a suitable animal model for atherosclerosis due to their sensitivity to dietary cholesterol. Moreover, rabbits have lipoprotein profiles that are more similar to humans than those of other laboratory animals. However, little is known about the transcriptomic information related to atherosclerosis in rabbits. We aimed to determine the changes in the livers of rabbits fed a normal chow diet (control) or high cholesterol diet (HCD) by histological examinations and RNA sequencing analysis. Compared with the control group, the lipid levels and small LDL subfractions in plasma were increased, and aortic atherosclerotic plaques were formed in the HCD group. Most importantly, HCD resulted in lipid accumulation and inflammation in the livers. Transcriptomic analysis of the liver showed that HCD induces 1183 differentially expressed genes (DEGs) that mainly participate in the regulation of inflammation and lipid metabolism. Furthermore, the signaling pathways involved in inflammation and lipid metabolism were enriched by KEGG pathway analysis. In addition, hepatic DEGs of the HCD group were further validated by real-time PCR. These results suggest that HCD causes liver lipid accumulation and inflammatory response. Although the relationships between these hepatic changes and atherogenesis need further investigation, these findings provide a fundamental framework for future research on human atherosclerosis using rabbit models.

The Brassica genus encompasses three diploid and three allopolyploid genomes, but a clear understanding of the evolution of agriculturally important traits via polyploidy is lacking. We assembled an allopolyploid Brassica juncea genome by shotgun and single-molecule reads integrated to genomic and genetic maps. We discovered that the A subgenomes of B. juncea and Brassica napus each had independent origins. Results suggested that A subgenomes of B. juncea were of monophyletic origin and evolved into vegetable-use and oil-use subvarieties. Homoeolog expression dominance occurs between subgenomes of allopolyploid B. juncea, in which differentially expressed genes display more selection potential than neutral genes. Homoeolog expression dominance in B. juncea has facilitated selection of glucosinolate and lipid metabolism genes in subvarieties used as vegetables and for oil production. These homoeolog expression dominance relationships among Brassicaceae genomes have contributed to selection response, predicting the directional effects of selection in a polyploid crop genome.