为研究温氏土鸡和白洛克鸡胚小肠寡肽转运载体PepT1(Solute carrier family 15 member 1)以及Na+/H+交换载体NHE2(Solute carrier family 9 member 2)和NHE3(Solute carrier family 9 member 3)mRNA的表达规律,选取产蛋日龄相近的温氏...为研究温氏土鸡和白洛克鸡胚小肠寡肽转运载体PepT1(Solute carrier family 15 member 1)以及Na+/H+交换载体NHE2(Solute carrier family 9 member 2)和NHE3(Solute carrier family 9 member 3)mRNA的表达规律,选取产蛋日龄相近的温氏土鸡和白洛克鸡所产种蛋各96枚,每个品种随机分为6组,每组16枚,在相同的条件下进行孵化。分别在9,12,14,17,19胚龄(E)和出壳当天(DOH),每个品种选取16枚鸡胚,采集小肠样品,采用Real-time RT-PCR方法检测小肠PepT1、NHE2和NHE3 mRNA的相对表达丰度。结果显示:从发育性变化来看,PepT1、NHE2和NHE3mRNA在温氏土鸡和白洛克鸡胚小肠的表达丰度都表现为随着胚龄的增加而上调,19胚龄后上调幅度较大;双因素方差分析表明,PepT1、NHE2和NHE3 mRNA的表达丰度在2个品种间无显著差异,但受发育阶段影响,PepT1 mRNA的表达丰度存在"品种×胚龄"的互作效应(P<0.000 1),NHE2和NHE3 mRNA表达丰度无"品种×胚龄"的互作效应(P>0.05)。说明PepT1、NHE2和NHE3 mRNA表达丰度在温氏土鸡和白洛克鸡胚小肠中具有相同的发育模式,其表达量受发育水平的影响,但品种间差异不显著。展开更多
近来发现蛋白质的消化产物在动物肠道内有相当一部分是以小肽的形式吸收和利用。克隆和分析两个结构相似的小肽转运载体 (Pep T1和 Pep T2 )揭示了哺乳动物和禽类的小肽转运机制。这些小肽转运载体识别二肽和三肽 ,其活性受日粮蛋白质...近来发现蛋白质的消化产物在动物肠道内有相当一部分是以小肽的形式吸收和利用。克隆和分析两个结构相似的小肽转运载体 (Pep T1和 Pep T2 )揭示了哺乳动物和禽类的小肽转运机制。这些小肽转运载体识别二肽和三肽 ,其活性受日粮蛋白质水平和各种激素的调控。目前对人、猪、鸡、大鼠、小鼠、兔子、绵羊等的 Pep T1的基因结构和蛋白质结构已有了系统的认识。就其生理特性、分布。展开更多
以酒石酸泰乐菌素为底药,探讨α-菠菜甾醇对小鼠小肠段药物转运体P-gp和PEPT1表达的影响。48只小鼠分为4组:α-菠菜甾醇组,酒石酸泰乐菌素组,α-菠菜甾醇和酒石酸泰乐菌素混合组,生理盐水对照组。每组按0.2 m L·10 g^(-1)体质量的...以酒石酸泰乐菌素为底药,探讨α-菠菜甾醇对小鼠小肠段药物转运体P-gp和PEPT1表达的影响。48只小鼠分为4组:α-菠菜甾醇组,酒石酸泰乐菌素组,α-菠菜甾醇和酒石酸泰乐菌素混合组,生理盐水对照组。每组按0.2 m L·10 g^(-1)体质量的剂量每天灌胃一次,共灌胃5 d,分别在1,3,5 d后处死1批采样。采用免疫组化的方法测定1,3,5 d的小鼠肠道上P-gp和PEPT1的表达。试验结果表明,α-菠菜甾醇组和混合组相对于对照组外排性药物转运体P-gp表达减少,而摄取性药物转运体PEPT1表达增多;酒石酸泰乐菌素组的外排性药物转运体P-gp表达增多,摄取性药物转运体PEPT1表达减少;且都随着用药时间的延长差异增大。表明α-菠菜甾醇具有抑制药物转运体P-gp表达和促进药物转运体PEPT1表达的作用。展开更多
Background: It is wel known that peptides play a vital role in the nutrition and health of dairy cows. Bovine oligopeptide transporter 1(bP epT 1) is involved in the peptide transport process in the gastrointestinal t...Background: It is wel known that peptides play a vital role in the nutrition and health of dairy cows. Bovine oligopeptide transporter 1(bP epT 1) is involved in the peptide transport process in the gastrointestinal tracts of dairy cows. However,little information is known in the characteristics of bP epT 1. Therefore, the purpose of this study was to characterize bP epT 1 functional y using a mammalian cel expression system. The uptake of radiolabeled dipeptide glycyl-sarcosine([3 H]-Gly-Sar)into the bP epT 1-transfected Chinese hamster ovary cel s was measured at various pH and substrate concentrations and with or without 15 other smal peptides that contained Met or Lys.Results: Western blot results showed that the abundance of bP epT 1 protein in the jejunum and ileum are the highest in the gastrointestinal tract of dairy cows. The uptake of [3 H]-Gly-Sar by b Pep T1-Chinese hamster ovary cells was dependent on time, p H, and substrate concentration, with a low Kmvalue of 0.94 ± 0.06 mmol/L and a maximum velocity of 20.80 ± 1.74 nmol/(mg protein · 5 min). Most of the di-and tripeptides were the substrates of b Pep T1,based on substrate-competitive studies. However, bP epT 1 has a higher affinity to the peptides with shorter chains, greater hydrophobicity, and negative or neutral charges.Conclusions: These results demonstrated for the first time the functional characteristics of bP epT 1, and they provide a new insight and better understanding into its vital role in absorbing a wide range of peptides from the digestive tract of dairy cows.展开更多
文摘为研究温氏土鸡和白洛克鸡胚小肠寡肽转运载体PepT1(Solute carrier family 15 member 1)以及Na+/H+交换载体NHE2(Solute carrier family 9 member 2)和NHE3(Solute carrier family 9 member 3)mRNA的表达规律,选取产蛋日龄相近的温氏土鸡和白洛克鸡所产种蛋各96枚,每个品种随机分为6组,每组16枚,在相同的条件下进行孵化。分别在9,12,14,17,19胚龄(E)和出壳当天(DOH),每个品种选取16枚鸡胚,采集小肠样品,采用Real-time RT-PCR方法检测小肠PepT1、NHE2和NHE3 mRNA的相对表达丰度。结果显示:从发育性变化来看,PepT1、NHE2和NHE3mRNA在温氏土鸡和白洛克鸡胚小肠的表达丰度都表现为随着胚龄的增加而上调,19胚龄后上调幅度较大;双因素方差分析表明,PepT1、NHE2和NHE3 mRNA的表达丰度在2个品种间无显著差异,但受发育阶段影响,PepT1 mRNA的表达丰度存在"品种×胚龄"的互作效应(P<0.000 1),NHE2和NHE3 mRNA表达丰度无"品种×胚龄"的互作效应(P>0.05)。说明PepT1、NHE2和NHE3 mRNA表达丰度在温氏土鸡和白洛克鸡胚小肠中具有相同的发育模式,其表达量受发育水平的影响,但品种间差异不显著。
文摘近来发现蛋白质的消化产物在动物肠道内有相当一部分是以小肽的形式吸收和利用。克隆和分析两个结构相似的小肽转运载体 (Pep T1和 Pep T2 )揭示了哺乳动物和禽类的小肽转运机制。这些小肽转运载体识别二肽和三肽 ,其活性受日粮蛋白质水平和各种激素的调控。目前对人、猪、鸡、大鼠、小鼠、兔子、绵羊等的 Pep T1的基因结构和蛋白质结构已有了系统的认识。就其生理特性、分布。
基金supported by the grants from the National Key Basic Research Program of China Ministry of Science and Technology(Grant No.2011CB100801)Funds for Distinguished Young Scientists of Zhejiang Province(R16C170002)
文摘Background: It is wel known that peptides play a vital role in the nutrition and health of dairy cows. Bovine oligopeptide transporter 1(bP epT 1) is involved in the peptide transport process in the gastrointestinal tracts of dairy cows. However,little information is known in the characteristics of bP epT 1. Therefore, the purpose of this study was to characterize bP epT 1 functional y using a mammalian cel expression system. The uptake of radiolabeled dipeptide glycyl-sarcosine([3 H]-Gly-Sar)into the bP epT 1-transfected Chinese hamster ovary cel s was measured at various pH and substrate concentrations and with or without 15 other smal peptides that contained Met or Lys.Results: Western blot results showed that the abundance of bP epT 1 protein in the jejunum and ileum are the highest in the gastrointestinal tract of dairy cows. The uptake of [3 H]-Gly-Sar by b Pep T1-Chinese hamster ovary cells was dependent on time, p H, and substrate concentration, with a low Kmvalue of 0.94 ± 0.06 mmol/L and a maximum velocity of 20.80 ± 1.74 nmol/(mg protein · 5 min). Most of the di-and tripeptides were the substrates of b Pep T1,based on substrate-competitive studies. However, bP epT 1 has a higher affinity to the peptides with shorter chains, greater hydrophobicity, and negative or neutral charges.Conclusions: These results demonstrated for the first time the functional characteristics of bP epT 1, and they provide a new insight and better understanding into its vital role in absorbing a wide range of peptides from the digestive tract of dairy cows.
