In forested stream ecosystems of the north and eastern United States, larvae of the aquatic crane fly Tipula abdominalis are important shredders of leaf litter detritus. T. abdominalis larvae harbor a dense and divers...In forested stream ecosystems of the north and eastern United States, larvae of the aquatic crane fly Tipula abdominalis are important shredders of leaf litter detritus. T. abdominalis larvae harbor a dense and diverse microbial community in their hindgut that may aide in the degradation oflignocellulose. In this study, the activities ofcellulolytic and hemicellulolytic enzymes were demonstrated from hindgut extracts and from bacterial isolates using model sugar substrates. One of the bacterial isolates was further characterized as a member of the family Microbacteriaceae. Taxonomic position of the isolate within this family was determined by a polyphasic approach, as is commonly employed for the separation of genera within the family Microbacteriaceae. The bacterial isolate is Gramtype positive, motile, non-sporulating, and rod-shaped. The G ＋ C content of the DNA is 64.9 mol%. The cell wall contains B2y type peptidoglycan, D- and L-diaminobutyric acid as the diamino acid, and rhamnose as the predominant sugar. The predominant fatty acids are 12-methyltetradecanoic acid （ai-C15：0） and 14-methylhexadecanoic acid （ai-C17：0）. The isolate forms a distinct lineage within the family Microbacteriaceae, as determined by 16S rRNA sequence analysis. We propose the name Crocebacterium ilecola gen. nov., sp. nov., to accommodate this bacterial isolate. The type species is T202T （ATCC BAA-1359; GenBank Accession DQ826511）.展开更多
The posterior gut of the Drosophila embryo, consisting of hindgut and Malpighian tubules, provides a simple,well-defined system where it is possible to use a genetic approach to define components essential for epithel...The posterior gut of the Drosophila embryo, consisting of hindgut and Malpighian tubules, provides a simple,well-defined system where it is possible to use a genetic approach to define components essential for epithelial morphogenesis.We review here the advantages of Drosophila as a model genetic organism, the morphogenesis of the epithelial structures of the posterior gut, and what is known about the genetic requirements to form these structures.In overview, primordia are patterned by expression of hierarchies of transcription factors; this leads to localized expression of cell signaling molecules, and finally, to the least understood step: modulation of cell adhesion and cell shape. We describe approaches to identify additional genes that are required for morphogenesis of these simple epithelia, particularly those that might play a structural role by affecting cell adhesion and cell shape.展开更多
This study was conducted to evaluate the effects of dietary crude protein(CP)and rumen-protected lysine(RPL)supplementation on lactation performance,amino acid(AA)balance,nitrogen(N)utilization and hindgut microbiota ...This study was conducted to evaluate the effects of dietary crude protein(CP)and rumen-protected lysine(RPL)supplementation on lactation performance,amino acid(AA)balance,nitrogen(N)utilization and hindgut microbiota in dairy cows.Treatments were in a 2×2 factorial arrangement,and the main effects were CP concentration(16%vs.18%)and RPL supplementation(with or without RPL at40 g/cow per day).Forty cows were randomly allocated to 4 groups:low-CP diet(LP),low-CP diet plus RPL(LPL),high-CP diet(HP),high-CP diet plus RPL(HPL).The experiment was conducted for 8 weeks.Results showed that RPL increased the dry matter intake(P<0.01),milk protein yield(P=0.04)and energy corrected milk(P=0.04),and tended to increase milk fat yield(P=0.06)and fat corrected milk(P=0.05).Cows in the HP group tended to have higher milk urea N(P=0.07).Plasma concentrations of Arg,Ile,Lys,Met,Pro,total essential AA and total nonessential AA were increased by RPL(P<0.05).The total essential AA,total nonessential AA and most AA(except Ile,Phe,Gly and Pro)were increased in the HP group(P<0.05).N excretion was increased in the HP group through an increase in urea N excretion(P<0.01)and an upward trend in plasma urea N(P=0.07).In addition,RPL tended to increase milk protein N secretion(P=0.08),milk N(P=0.07)and microbial protein synthesis(P=0.06),and decreased plasma urea N(P<0.001).In the hindgut,the bacterial community were different between the LP and LPL groups(P<0.01).The probiotic abundances of Christensenellaceae_R-7_group and Acinetobacter were increased by RPL(P=0.03 and 0.03,respectively).The pathogenic abundances of Clostridium_sensu_stricto_1(P<0.001)and Turicibacter(P<0.01)were decreased by RPL.In conclusion,supplementing RPL with low dietary CP could balance AA supply and increase milk protein yield,resulting in an improvement in N utilization efficiency,and altered the composition of the hindgut microbiota to favor the lactation performance of dairy cows.展开更多
Early weaning induces intestinal injury,leading to a series of long-term symptoms such as inflammation,malabsorption and diarrhea.In this study,we hypothesized that microbes and theirmetabolitesmodulate the host's...Early weaning induces intestinal injury,leading to a series of long-term symptoms such as inflammation,malabsorption and diarrhea.In this study,we hypothesized that microbes and theirmetabolitesmodulate the host's inflammatory response to early weaning stress in a goatmodel.A total of 18 female Tibetan goat kids(n?9)wereweaned fromtheirmothers at 28 d(D28)and 60 d(D60)postpartum.D60 and D28 groupswere fed the same solid diet ad libitum fromweaning to 75 d of age.The colonic epithelium was subject to RNAsequencing,the caecal digesta metabolomics were assessed by liquid chromatographyetandem mass spectrometry(LC-MS/MS),and the caecal microbiota composition was analysed by 16S ribosomal RNA gene sequencing.We foundthatearlyweaningsubstantially increased the colonic pro-apoptotic gene expressionof B-cell lymphoma associated X(Bax),caspase-9,and caspase-3,and decreased the expression of zonula occludens-1(ZO-1)and claudin-1(P<0.01).In addition,a significant Bacteroides acidifaciens enrichmentwas observed in the hindgut of early-weaned goats(P<0.01),which negatively correlated with lysophosphatidylcholine products.Similarly,the chemokine signaling,IL-17 signaling,and peroxisome proliferatorsactivated receptor(PPAR)signaling pathways were upregulated in the colonic mucosa of the early-weaned goats.By applying caecal microbiota transplantation from goats to defaunated C57/6J mice,we confirmed that caecalmicrobiota of D28 goat kids increased the relative abundance of B.acidifaciens and significantly upregulated the genes of Bax,G proteinecoupled receptor(GPR)109A,GPR 43,fatty acid binding protein 6,nuclear receptor subfamily 1 group H member 3,angiotensin converting enzyme 2,and IL-6 expression(P<0.05),and decreased ZO-1,and claudin-1 protein expression in the mice jejunum and colon(P<0.001).These results proposed that the hindgut microbiota andmetabolites mediate the barrier functionweakening duringearlyweaning,and the relative abundance of B.acidifacienswas negatively correlatedwiththe hindgut barrier gene expression.Th展开更多
Chitin deacetylases(CDAs,including CDAI and CDA2)are considered key enzymes for body cuticle formation and tracheal morphogenesis in various insect species.However,their functions in the formation of the cuticular int...Chitin deacetylases(CDAs,including CDAI and CDA2)are considered key enzymes for body cuticle formation and tracheal morphogenesis in various insect species.However,their functions in the formation of the cuticular intima of the foregut and hindgut are unclear.Here,we investigated the roles of their respective genes LmCDAI and Lm-CD42 in this process,in the hemimetabolous insect Locusta migratoria.Transcripts of LmCDAI and LmCDA2 were highly expressed both before and after molting in the foregut.In the hindgut,their expression was high only before molting.In both the foregut and hindgut,LmCDA1 protein was localized in the basal half of the chitin matrix(procuti-cle),whereas LmCDA2 was detected in the upper half of the procuticle.K nockdown of LmCDAI by RNA interference(RNAi)in 5th-instar nymphs caused no visible defcts of the hindgut cuticle.By contrast,the chitinous lamellae of the cuticular intima in the foregut of knockdown animals were less compact than in control animals.RNAi against LmCDA2 led to thickening of both the foregut and hindgut cuticles,with a greater number of thinner laminae than in the respective control cuticles.Taken together,our results show that LmCDAI and LmCDA2 have distinct,but overlapping,functions in chitin organization in the foregut cuticle.However,in the hindgut,this process seems independent of LmCDA1 activity but requires LmCDA2 function.Thus,the CDAs reflect tissue-specific differences in cuticular organization and function,which need further detailed molecular and histological analyses for full comprehension.展开更多
文摘In forested stream ecosystems of the north and eastern United States, larvae of the aquatic crane fly Tipula abdominalis are important shredders of leaf litter detritus. T. abdominalis larvae harbor a dense and diverse microbial community in their hindgut that may aide in the degradation oflignocellulose. In this study, the activities ofcellulolytic and hemicellulolytic enzymes were demonstrated from hindgut extracts and from bacterial isolates using model sugar substrates. One of the bacterial isolates was further characterized as a member of the family Microbacteriaceae. Taxonomic position of the isolate within this family was determined by a polyphasic approach, as is commonly employed for the separation of genera within the family Microbacteriaceae. The bacterial isolate is Gramtype positive, motile, non-sporulating, and rod-shaped. The G ＋ C content of the DNA is 64.9 mol%. The cell wall contains B2y type peptidoglycan, D- and L-diaminobutyric acid as the diamino acid, and rhamnose as the predominant sugar. The predominant fatty acids are 12-methyltetradecanoic acid （ai-C15：0） and 14-methylhexadecanoic acid （ai-C17：0）. The isolate forms a distinct lineage within the family Microbacteriaceae, as determined by 16S rRNA sequence analysis. We propose the name Crocebacterium ilecola gen. nov., sp. nov., to accommodate this bacterial isolate. The type species is T202T （ATCC BAA-1359; GenBank Accession DQ826511）.
文摘The posterior gut of the Drosophila embryo, consisting of hindgut and Malpighian tubules, provides a simple,well-defined system where it is possible to use a genetic approach to define components essential for epithelial morphogenesis.We review here the advantages of Drosophila as a model genetic organism, the morphogenesis of the epithelial structures of the posterior gut, and what is known about the genetic requirements to form these structures.In overview, primordia are patterned by expression of hierarchies of transcription factors; this leads to localized expression of cell signaling molecules, and finally, to the least understood step: modulation of cell adhesion and cell shape. We describe approaches to identify additional genes that are required for morphogenesis of these simple epithelia, particularly those that might play a structural role by affecting cell adhesion and cell shape.
基金financially supported by National Natural Science Foundation of China (32172742 and 32202688)the Natural Science Foundation of Zhejiang Province (LQ22C170002)+1 种基金the Zhejiang Provincial Science and Technology Plan Project(2022C04038)the Zhejiang Animal Husbandry Industry Technology Project
文摘This study was conducted to evaluate the effects of dietary crude protein(CP)and rumen-protected lysine(RPL)supplementation on lactation performance,amino acid(AA)balance,nitrogen(N)utilization and hindgut microbiota in dairy cows.Treatments were in a 2×2 factorial arrangement,and the main effects were CP concentration(16%vs.18%)and RPL supplementation(with or without RPL at40 g/cow per day).Forty cows were randomly allocated to 4 groups:low-CP diet(LP),low-CP diet plus RPL(LPL),high-CP diet(HP),high-CP diet plus RPL(HPL).The experiment was conducted for 8 weeks.Results showed that RPL increased the dry matter intake(P<0.01),milk protein yield(P=0.04)and energy corrected milk(P=0.04),and tended to increase milk fat yield(P=0.06)and fat corrected milk(P=0.05).Cows in the HP group tended to have higher milk urea N(P=0.07).Plasma concentrations of Arg,Ile,Lys,Met,Pro,total essential AA and total nonessential AA were increased by RPL(P<0.05).The total essential AA,total nonessential AA and most AA(except Ile,Phe,Gly and Pro)were increased in the HP group(P<0.05).N excretion was increased in the HP group through an increase in urea N excretion(P<0.01)and an upward trend in plasma urea N(P=0.07).In addition,RPL tended to increase milk protein N secretion(P=0.08),milk N(P=0.07)and microbial protein synthesis(P=0.06),and decreased plasma urea N(P<0.001).In the hindgut,the bacterial community were different between the LP and LPL groups(P<0.01).The probiotic abundances of Christensenellaceae_R-7_group and Acinetobacter were increased by RPL(P=0.03 and 0.03,respectively).The pathogenic abundances of Clostridium_sensu_stricto_1(P<0.001)and Turicibacter(P<0.01)were decreased by RPL.In conclusion,supplementing RPL with low dietary CP could balance AA supply and increase milk protein yield,resulting in an improvement in N utilization efficiency,and altered the composition of the hindgut microbiota to favor the lactation performance of dairy cows.
基金Qinghai Province Key R&D and Transformation Plan(2020-NK-127)Tibet Science and Technology Department's"13th Five-Year Plan"Major Agriculture Project(XZ201901NA02)+2 种基金the Key Technology R&D Program of Xinjiang Groups(2020AB016)Science and Technology Program of Tibet(XZ202001YD0017C)Agriculture Research System of China(CARS-39-12).
文摘Early weaning induces intestinal injury,leading to a series of long-term symptoms such as inflammation,malabsorption and diarrhea.In this study,we hypothesized that microbes and theirmetabolitesmodulate the host's inflammatory response to early weaning stress in a goatmodel.A total of 18 female Tibetan goat kids(n?9)wereweaned fromtheirmothers at 28 d(D28)and 60 d(D60)postpartum.D60 and D28 groupswere fed the same solid diet ad libitum fromweaning to 75 d of age.The colonic epithelium was subject to RNAsequencing,the caecal digesta metabolomics were assessed by liquid chromatographyetandem mass spectrometry(LC-MS/MS),and the caecal microbiota composition was analysed by 16S ribosomal RNA gene sequencing.We foundthatearlyweaningsubstantially increased the colonic pro-apoptotic gene expressionof B-cell lymphoma associated X(Bax),caspase-9,and caspase-3,and decreased the expression of zonula occludens-1(ZO-1)and claudin-1(P<0.01).In addition,a significant Bacteroides acidifaciens enrichmentwas observed in the hindgut of early-weaned goats(P<0.01),which negatively correlated with lysophosphatidylcholine products.Similarly,the chemokine signaling,IL-17 signaling,and peroxisome proliferatorsactivated receptor(PPAR)signaling pathways were upregulated in the colonic mucosa of the early-weaned goats.By applying caecal microbiota transplantation from goats to defaunated C57/6J mice,we confirmed that caecalmicrobiota of D28 goat kids increased the relative abundance of B.acidifaciens and significantly upregulated the genes of Bax,G proteinecoupled receptor(GPR)109A,GPR 43,fatty acid binding protein 6,nuclear receptor subfamily 1 group H member 3,angiotensin converting enzyme 2,and IL-6 expression(P<0.05),and decreased ZO-1,and claudin-1 protein expression in the mice jejunum and colon(P<0.001).These results proposed that the hindgut microbiota andmetabolites mediate the barrier functionweakening duringearlyweaning,and the relative abundance of B.acidifacienswas negatively correlatedwiththe hindgut barrier gene expression.Th
基金the National Natural Science Foundation of China(Grant No.31672364,31761133021,32072419,31701794,31801749)the Pro-gram for Top Young Academic Leaders of Higher Learn-ing Institutions of Shanxi(TYAL)2017+1 种基金Scientific and Technological Innovation Programs of Higher Edu-cation Institutions in Shanxi(2017104)BM's contribu-tion was supported by the German Research Foundation(DFG grant MO1714/10-1).
文摘Chitin deacetylases(CDAs,including CDAI and CDA2)are considered key enzymes for body cuticle formation and tracheal morphogenesis in various insect species.However,their functions in the formation of the cuticular intima of the foregut and hindgut are unclear.Here,we investigated the roles of their respective genes LmCDAI and Lm-CD42 in this process,in the hemimetabolous insect Locusta migratoria.Transcripts of LmCDAI and LmCDA2 were highly expressed both before and after molting in the foregut.In the hindgut,their expression was high only before molting.In both the foregut and hindgut,LmCDA1 protein was localized in the basal half of the chitin matrix(procuti-cle),whereas LmCDA2 was detected in the upper half of the procuticle.K nockdown of LmCDAI by RNA interference(RNAi)in 5th-instar nymphs caused no visible defcts of the hindgut cuticle.By contrast,the chitinous lamellae of the cuticular intima in the foregut of knockdown animals were less compact than in control animals.RNAi against LmCDA2 led to thickening of both the foregut and hindgut cuticles,with a greater number of thinner laminae than in the respective control cuticles.Taken together,our results show that LmCDAI and LmCDA2 have distinct,but overlapping,functions in chitin organization in the foregut cuticle.However,in the hindgut,this process seems independent of LmCDA1 activity but requires LmCDA2 function.Thus,the CDAs reflect tissue-specific differences in cuticular organization and function,which need further detailed molecular and histological analyses for full comprehension.
