Background In the modern sheep production systems,the reproductive performance of ewes determines the economic profitability of farming.Revealing the genetic mechanisms underlying differences in the litter size is imp...Background In the modern sheep production systems,the reproductive performance of ewes determines the economic profitability of farming.Revealing the genetic mechanisms underlying differences in the litter size is important for the selection and breeding of highly prolific ewes.Hu sheep,a high-quality Chinese sheep breed,is known for its high fecundity and is often used as a model to study prolificacy traits.In the current study,animals were divided into two groups according to their delivery rates in three consecutive lambing seasons(namely,the high and low reproductive groups with≥3 lambs and one lamb per season,n=3,respectively).The ewes were slaughtered within 12 h of estrus,and unilateral ovarian tissues were collected and analyzed by 10×Genomics single-cell RNA sequencing.Results A total of 5 types of somatic cells were identified and corresponding expression profiles were mapped in the ovaries of each group.Noticeably,the differences in the ovary somatic cell expression profiles between the high and low reproductive groups were mainly clustered in the granulosa cells.Furthermore,four granulosa cell subtypes were identified.GeneSwitches analysis revealed that the abundance of JPH1 expression and the reduction of LOC101112291 expression could lead to different evolutionary directions of the granulosa cells.Additionally,the expression levels of FTH1 and FTL in mural granulosa cells of the highly reproductive group were significantly higher.These genes inhibit necroptosis and ferroptosis of mural granulosa cells,which helps prevent follicular atresia.Conclusions This study provides insights into the molecular mechanisms underlying the high fecundity of Hu sheep.The differences in gene expression profiles,particularly in the granulosa cells,suggest that these cells play a critical role in female prolificacy.The findings also highlight the importance of genes such as JPH1,LOC101112291,FTH1,and FTL in regulating granulosa cell function and follicular development.展开更多
High-protein diet could cause an increase in protein fermentation in the large intestine, leading to an increased production of potentially detrimental metabolites. We hypothesized that an increase in corn resistant s...High-protein diet could cause an increase in protein fermentation in the large intestine, leading to an increased production of potentially detrimental metabolites. We hypothesized that an increase in corn resistant starch content may attenuate the protein fermentation. The aim of this study was to evaluate the effect of resistant starch on protein fermentation by inocula from large intestine of pigs using in vitro cultivation. Fermentation patterns were analyzed during a 24-h incubation of cecal and colonic digesta with varying corn resistant starch contents, using casein protein as sole nitrogen source. The results showed that the concentration of short-chain fatty acids(SCFA) and cumulative gas production were significantly increased(P < 0.05), while ammonia-nitrogen(NH_3-N) and branched-chain fatty acids(BCFA), which indicated protein fermentation, decreased when the corn resistant starch levels increased(P < 0.05). The copies of total bacteria, Bifidobacterium and Lactobacillus were significantly increased with the increased corn resistant starch levels after incubation(P < 0.05). The copies of the Bifidobacterium and Lactobacillus in cecum were significantly higher than those in colon(P < 0.05). We conclude that the addition of corn resistant starch weakens the protein fermentation by influencing microbial population and reducing protein fermentation in the cecum and colon in vitro.展开更多
Anthocyanin accumulation is a common phenomenon seen in plants under environmental stress. In this study,we identified a new allele of ROOT HAIR DEFECTIVE3（RHD3）showing an anthocyanin overaccumulation phenotype unde...Anthocyanin accumulation is a common phenomenon seen in plants under environmental stress. In this study,we identified a new allele of ROOT HAIR DEFECTIVE3（RHD3）showing an anthocyanin overaccumulation phenotype under nitrogen starvation conditions. It is known that ethylene negatively regulates light- and sucrose-induced anthocyanin biosynthesis. We hypothesized that RHD3 achieves its negative effect on anthocyanin biosynthesis via an ethylene-regulating pathway. In support of this, similar to rhd3 mutants, the Arabidopsis ethylene signaling mutants etr1, ein2, and ein3/eil1 showed an anthocyanin overaccumulation phenotype under nitrogen starvation conditions. The ethylene precursor ACC strongly suppressed anthocyanin accumulation, dependent on ETR1, EIN2, EIN3/EIL1, and, partially, RHD3. In addition,inactivating RHD3 partially reversed the suppressive effect of ETO1 inactivation-evoked endogenous ethylene production on anthocyanin accumulation. The expression of nitrogen starvation-induced anthocyanin biosynthesis genes was negatively regulated by RHD3, but ethylene response genes were Researchpositively regulated by RHD3. Wild-type seedlings overexpressing RHD3 showed similar phenotypes to rhd3 mutants,indicating the existence of a fine-tuned relationship between gene expression and function. RHD3 was initially identified as a gene involved in root hair development. This study uncovered a new physiological function of RHD3 in nitrogen starvationinduced anthocyanin accumulation and ethylene homeostasis.展开更多
The ongoing coronavirus disease 2019(COVID-19)pandemic is a serious challenge faced by the global community.Physical scientists can help medical workers and biomedical scientists,engineers,and practitioners,who are wo...The ongoing coronavirus disease 2019(COVID-19)pandemic is a serious challenge faced by the global community.Physical scientists can help medical workers and biomedical scientists,engineers,and practitioners,who are working on the front line,to slow down and eventually contain the spread of the COVID-19 virus.This review is focused on the physicochemical characteristics,including composition,aerodynamics,and drying behavior of respiratory droplets as a complex and multicomponent soft matter system,which are the main carrier of the virus for interpersonal transmission.The distribution and dynamics of virus particles within a droplet are also discussed.Understanding the characteristics of virus-laden respiratory droplets can lead to better design of personal protective equipment,frequently touched surfaces such as door knobs and touchscreens,and filtering equipment for indoor air circulation.Such an understanding also provides the scientific basis of public policy,including social distancing rules and public hygiene guidelines,implemented by governments around the world.展开更多
Background Gut microbiota alterations have been implicated in the pathogenesis of coronavirus disease 2019(COVID-19).This study aimed to explore gut microbiota changes in a prospective cohort of COVID-19 children and ...Background Gut microbiota alterations have been implicated in the pathogenesis of coronavirus disease 2019(COVID-19).This study aimed to explore gut microbiota changes in a prospective cohort of COVID-19 children and their asymptomatic caregivers infected with the severe acute respiratory syndrome coronavirus type 2(SARS-CoV-2)Omicron variant.Methods A total of 186 participants,including 59 COVID-19 children,50 asymptomatic adult caregivers,52 healthy children(HC),and 25 healthy adults(HA),were recruited between 15 April and 31 May 2022.The gut microbiota composition was determined by 16S rRNA gene sequencing in fecal samples collected from the participants.Gut microbiota functional profling was performed by using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States(PICRUSt)software.Results The gut microbiota analysis of beta diversity revealed that the fecal microbial community of COVID-19 children remained far distantly related to HC.The relative abundances of the phyla Actinobacteria and Firmicutes were decreased,whereas Bacteroidetes,Proteobacteria,and Verrucomicrobiota were increased in COVID-19 children.Feces from COVID-19 children exhibited notably lower abundances of the genera Blautia,Bifdobacterium,Fusicatenibacter,Streptococcus,and Romboutsia and higher abundances of the genera Prevotella,Lachnoclostridium,Escherichia-Shigella,and Bacteroides than those from HC.The enterotype distributions of COVID-19 children were characterized by a high prevalence of enterotype Bacteroides.Similar changes in gut microbiota compositions were observed in asymptomatic caregivers.Furthermore,the microbial metabolic activities of KEGG(Kyoto Encyclopedia of Genes and Genomes)and COG(cluster of orthologous groups of proteins)pathways were perturbed in feces from subjects infected with the SARS-CoV-2 Omicron variant.Conclusion Our data reveal altered gut microbiota compositions in both COVID-19 children and their asymptomatic caregivers infected with the SARS-CoV-2 Omicron variant,which further implicates the critical role of gut microbiota in COVID-19 pathogenesis.展开更多
基金supported by the mutton sheep industry technology system construction project of Shaanxi Province(NYKJ-2021-YL(XN)43).
文摘Background In the modern sheep production systems,the reproductive performance of ewes determines the economic profitability of farming.Revealing the genetic mechanisms underlying differences in the litter size is important for the selection and breeding of highly prolific ewes.Hu sheep,a high-quality Chinese sheep breed,is known for its high fecundity and is often used as a model to study prolificacy traits.In the current study,animals were divided into two groups according to their delivery rates in three consecutive lambing seasons(namely,the high and low reproductive groups with≥3 lambs and one lamb per season,n=3,respectively).The ewes were slaughtered within 12 h of estrus,and unilateral ovarian tissues were collected and analyzed by 10×Genomics single-cell RNA sequencing.Results A total of 5 types of somatic cells were identified and corresponding expression profiles were mapped in the ovaries of each group.Noticeably,the differences in the ovary somatic cell expression profiles between the high and low reproductive groups were mainly clustered in the granulosa cells.Furthermore,four granulosa cell subtypes were identified.GeneSwitches analysis revealed that the abundance of JPH1 expression and the reduction of LOC101112291 expression could lead to different evolutionary directions of the granulosa cells.Additionally,the expression levels of FTH1 and FTL in mural granulosa cells of the highly reproductive group were significantly higher.These genes inhibit necroptosis and ferroptosis of mural granulosa cells,which helps prevent follicular atresia.Conclusions This study provides insights into the molecular mechanisms underlying the high fecundity of Hu sheep.The differences in gene expression profiles,particularly in the granulosa cells,suggest that these cells play a critical role in female prolificacy.The findings also highlight the importance of genes such as JPH1,LOC101112291,FTH1,and FTL in regulating granulosa cell function and follicular development.
基金Project supported by the Zhejiang Provincial Natural Science Foundation of China(No.LY15E050003)the Specialized Research Fund for the Doctoral Program of Higher Education of China(No.20120101130003)+1 种基金the Key Project of Science and Technology Program of Zhejiang Province(No.2013C01135)the Fundamental Research Funds for the Central Universities(No.2015QNA4003),China
基金supported by grants from National Key Basic Research Program of China (2013CB127300)National Natural Science Foundation of China (31430082)Natural Science Foundation of Jiangsu Province (BK20130058)
文摘High-protein diet could cause an increase in protein fermentation in the large intestine, leading to an increased production of potentially detrimental metabolites. We hypothesized that an increase in corn resistant starch content may attenuate the protein fermentation. The aim of this study was to evaluate the effect of resistant starch on protein fermentation by inocula from large intestine of pigs using in vitro cultivation. Fermentation patterns were analyzed during a 24-h incubation of cecal and colonic digesta with varying corn resistant starch contents, using casein protein as sole nitrogen source. The results showed that the concentration of short-chain fatty acids(SCFA) and cumulative gas production were significantly increased(P < 0.05), while ammonia-nitrogen(NH_3-N) and branched-chain fatty acids(BCFA), which indicated protein fermentation, decreased when the corn resistant starch levels increased(P < 0.05). The copies of total bacteria, Bifidobacterium and Lactobacillus were significantly increased with the increased corn resistant starch levels after incubation(P < 0.05). The copies of the Bifidobacterium and Lactobacillus in cecum were significantly higher than those in colon(P < 0.05). We conclude that the addition of corn resistant starch weakens the protein fermentation by influencing microbial population and reducing protein fermentation in the cecum and colon in vitro.
基金supported by the Program for Innovative Research Team in Universities of Inner Mongolia Autonomous Region,Chinathe High Level Scientific Research Foundation for the Introduction of Talent at the Inner Mongolia University(125107)
文摘Anthocyanin accumulation is a common phenomenon seen in plants under environmental stress. In this study,we identified a new allele of ROOT HAIR DEFECTIVE3（RHD3）showing an anthocyanin overaccumulation phenotype under nitrogen starvation conditions. It is known that ethylene negatively regulates light- and sucrose-induced anthocyanin biosynthesis. We hypothesized that RHD3 achieves its negative effect on anthocyanin biosynthesis via an ethylene-regulating pathway. In support of this, similar to rhd3 mutants, the Arabidopsis ethylene signaling mutants etr1, ein2, and ein3/eil1 showed an anthocyanin overaccumulation phenotype under nitrogen starvation conditions. The ethylene precursor ACC strongly suppressed anthocyanin accumulation, dependent on ETR1, EIN2, EIN3/EIL1, and, partially, RHD3. In addition,inactivating RHD3 partially reversed the suppressive effect of ETO1 inactivation-evoked endogenous ethylene production on anthocyanin accumulation. The expression of nitrogen starvation-induced anthocyanin biosynthesis genes was negatively regulated by RHD3, but ethylene response genes were Researchpositively regulated by RHD3. Wild-type seedlings overexpressing RHD3 showed similar phenotypes to rhd3 mutants,indicating the existence of a fine-tuned relationship between gene expression and function. RHD3 was initially identified as a gene involved in root hair development. This study uncovered a new physiological function of RHD3 in nitrogen starvationinduced anthocyanin accumulation and ethylene homeostasis.
基金This work was supported by the National Science Foundation(No.DMR-1944887)Ting Ge is supported by the start-up funds from the University of South CarolinaThe material prepared by Shengfeng Cheng is based upon work supported by the National Science Foundation under Grant DMR-1944887.
文摘The ongoing coronavirus disease 2019(COVID-19)pandemic is a serious challenge faced by the global community.Physical scientists can help medical workers and biomedical scientists,engineers,and practitioners,who are working on the front line,to slow down and eventually contain the spread of the COVID-19 virus.This review is focused on the physicochemical characteristics,including composition,aerodynamics,and drying behavior of respiratory droplets as a complex and multicomponent soft matter system,which are the main carrier of the virus for interpersonal transmission.The distribution and dynamics of virus particles within a droplet are also discussed.Understanding the characteristics of virus-laden respiratory droplets can lead to better design of personal protective equipment,frequently touched surfaces such as door knobs and touchscreens,and filtering equipment for indoor air circulation.Such an understanding also provides the scientific basis of public policy,including social distancing rules and public hygiene guidelines,implemented by governments around the world.
基金supported by the grants from the National Natural Science Foundation of China(No.81870373)the Natural Science Foundation of Shanghai(No.22ZR1451800).
文摘Background Gut microbiota alterations have been implicated in the pathogenesis of coronavirus disease 2019(COVID-19).This study aimed to explore gut microbiota changes in a prospective cohort of COVID-19 children and their asymptomatic caregivers infected with the severe acute respiratory syndrome coronavirus type 2(SARS-CoV-2)Omicron variant.Methods A total of 186 participants,including 59 COVID-19 children,50 asymptomatic adult caregivers,52 healthy children(HC),and 25 healthy adults(HA),were recruited between 15 April and 31 May 2022.The gut microbiota composition was determined by 16S rRNA gene sequencing in fecal samples collected from the participants.Gut microbiota functional profling was performed by using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States(PICRUSt)software.Results The gut microbiota analysis of beta diversity revealed that the fecal microbial community of COVID-19 children remained far distantly related to HC.The relative abundances of the phyla Actinobacteria and Firmicutes were decreased,whereas Bacteroidetes,Proteobacteria,and Verrucomicrobiota were increased in COVID-19 children.Feces from COVID-19 children exhibited notably lower abundances of the genera Blautia,Bifdobacterium,Fusicatenibacter,Streptococcus,and Romboutsia and higher abundances of the genera Prevotella,Lachnoclostridium,Escherichia-Shigella,and Bacteroides than those from HC.The enterotype distributions of COVID-19 children were characterized by a high prevalence of enterotype Bacteroides.Similar changes in gut microbiota compositions were observed in asymptomatic caregivers.Furthermore,the microbial metabolic activities of KEGG(Kyoto Encyclopedia of Genes and Genomes)and COG(cluster of orthologous groups of proteins)pathways were perturbed in feces from subjects infected with the SARS-CoV-2 Omicron variant.Conclusion Our data reveal altered gut microbiota compositions in both COVID-19 children and their asymptomatic caregivers infected with the SARS-CoV-2 Omicron variant,which further implicates the critical role of gut microbiota in COVID-19 pathogenesis.
