Browsing by Author "Wang, Yun"

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    Effects of Individual Essential Amino Acids on Growth Rates of Young Rats Fed a Low-Protein Diet
    Liu, Wei; Wang, Tianyi; Zhao, Kai; Hanigan, Mark D.; Lin, Xueyan; Hu, Zhiyong; Hou, Qiuling; Wang, Yun; Wang, Zhonghua (MDPI, 2024-03-20)
    To investigate the effects of individual essential amino acids (EAA) on growth and the underlying mechanisms, EAA individually supplemented a low-protein (LP) diet fed to young rats in the present study. Treatments were an LP diet that contained 6% crude protein (CP), a high-protein (HP) diet that contained 18% CP, and 10 LP diets supplemented with individual EAA to achieve an EAA supply equal to that of the HP diet. The CP concentration of the LP diet was ascertained from the results of the first experiment, which examined the effects of dietary CP concentrations on growth rates, with CP ranging from 2% to 26%. Weight gain was increased with the supplementation of His, Ile, Lys, Thr, or Trp as compared to the LP diet (p < 0.05). Feed intake was greater for the His-, Lys-, and Thr-supplemented treatments as compared to the LP group (p < 0.05). Protein utilization efficiency was lower for the HP group than other groups (p < 0.01). The supplementation of Leu, Lys, and Val led to reduced protein utilization efficiency (p < 0.05), but the supplementation of Thr and Trp led to greater efficiency than the LP group (p < 0.05). Compared to the LP group, plasma urea concentrations were elevated with individual EAA supplementation, with the exception of the Thr addition. The added EAA resulted in increased concentrations of the corresponding EAA in plasma, except for Arg and Phe supplementation. The supplementation of Arg, His, Leu, Lys, and Met individually stimulated mTORC1 pathway activity (p < 0.05), and all EAA resulted in the decreased expression of ATF4 (p < 0.05). In summary, the supplementation of His, Ile, Lys, Thr, or Trp to an LP diet improved the growth performance of young rats. Responses to His and Lys additions were related to the activated mTORC1 pathway and feed intake increases. The improved growth performance resulting from the addition of a single EAA is not solely attributed to the increased plasma availability of EAA. Rather, it may be the consequence of a confluence of factors encompassing signaling pathways, the availability of amino acids, and other associated elements. The additivity of these factors results in independent responses to several EAA with no order of limitation, as is universally encoded in growth models for all production animal species.
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    Genus-Wide Characterization of Bumblebee Genomes Provides Insights into Their Evolution and Variation in Ecological and Behavioral Traits
    Sun, Cheng; Huang, Jiaxing; Wang, Yun; Zhao, Xiaomeng; Su, Long; Thomas, Gregg W. C.; Zhao, Mengya; Zhang, Xingtan; Jungreis, Irwin; Kellis, Manolis; Vicario, Saverio; Sharakhov, Igor V.; Bondarenko, Semen M.; Hasselmann, Martin; Kim, Chang N.; Paten, Benedict; Penso-Dolfin, Luca; Wang, Li; Chang, Yuxiao; Gao, Qiang; Ma, Ling; Ma, Lina; Zhang, Zhang; Zhang, Hongbo; Zhang, Huahao; Ruzzante, Livio; Robertson, Hugh M.; Zhu, Yihui; Liu, Yanjie; Yang, Huipeng; Ding, Lele; Wang, Quangui; Ma, Dongna; Xu, Weilin; Liang, Cheng; Itgen, Michael W.; Mee, Lauren; Cao, Gang; Zhang, Ze; Sadd, Ben M.; Hahn, Matthew W.; Schaack, Sarah; Barribeau, Seth M.; Williams, Paul H.; Waterhouse, Robert M.; Mueller, Rachel Lockridge (Oxford University Press, 2021-02-01)
    Bumblebees are a diverse group of globally important pollinators in natural ecosystems and for agricultural food production. With both eusocial and solitary life-cycle phases, and some social parasite species, they are especially interesting models to understand social evolution, behavior, and ecology. Reports of many species in decline point to pathogen transmission, habitat loss, pesticide usage, and global climate change, as interconnected causes. These threats to bumblebee diversity make our reliance on a handful of well-studied species for agricultural pollination particularly precarious. To broadly sample bumblebee genomic and phenotypic diversity, we de novo sequenced and assembled the genomes of 17 species, representing all 15 subgenera, producing the first genus-wide quantification of genetic and genomic variation potentially underlying key ecological and behavioral traits. The species phylogeny resolves subgenera relationships, whereas incomplete lineage sorting likely drives high levels of gene tree discordance. Five chromosome-level assemblies show a stable 18-chromosome karyotype, with major rearrangements creating 25 chromosomes in social parasites. Differential transposable element activity drives changes in genome sizes, with putative domestications of repetitive sequences influencing gene coding and regulatory potential. Dynamically evolving gene families and signatures of positive selection point to genus-wide variation in processes linked to foraging, diet and metabolism, immunity and detoxification, as well as adaptations for life at high altitudes. Our study reveals how bumblebee genes and genomes have evolved across the Bombus phylogeny and identifies variations potentially linked to key ecological and behavioral traits of these important pollinators.
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    Responses in splanchnic and mammary amino acid metabolism to short-term graded removal of methionine in lactating goats
    Li, Yantao; Hanigan, Mark D.; Lin, Xueyan; Hu, Zhiyong; Yan, Zhengui; Hou, Qiuling; Wang, Yun; Wang, Zhonghua (Keai Publishing, 2023-06)
    Four multi-catheterized lactating goats were used in a 4 x 4 Latin square experiment to investigate the responses of amino acid metabolism in portal-drained viscera (PDV), liver, and mammary glands to short-term varying supplies of methionine (Met). During the last 45 h in each experimental period, goats were fasted for 12 h and then abomasally infused with an amino acid (AA) mixture plus glucose for 33 h. Treatments consisted of graded removal of Met from an infused AA mixture to achieve Met content in the infusate of 100% (complete), 60%, 30%, or 0% that in casein. Graded Met removal decreased the pro-duction of milk, milk protein, lactose, and fat linearly whilst also decreasing arterial Met concentration linearly (P < 0.05). Meanwhile, net PDV uptake and liver removal of Met decreased linearly (P < 0.05) due to decreased Met affinity of PDV and liver (P < 0.05). Net mammary uptake of Met (P > 0.1) was maintained as Met supply declined. This was achieved through increased mammary affinity (P < 0.05) and increased mammary blood flow (P < 0.05) totally offsetting the negative effect of decreased circu-lating Met concentration. Graded removal of Met from the infusate linearly decreased mammary uptake -to-milk output ratios of Met (P < 0.05) and tended to decrease essential amino acid (EAA) linearly (0.05 < P < 0.1). Treatments also linearly decreased circulating concentration of prolactin and linearly increased insulin concentration (P < 0.05). In conclusion, results of the present study indicated there were several mechanisms used to mitigate a Met deficiency, including reduced catabolism of Met in PDV, liver, and peripheral tissue (including mammary glands) and a linear increase in mammary blood flow. The observed decreases in milk protein production as Met supply decreased appear to be a result of regulatory events which may have been driven by decreased circulating prolactin, rather than as a result of decreased mammary Met uptake.(c) 2023 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).