含蛋氨酸二肽影响奶牛乳腺上皮细胞乳蛋白合成相关基因表达  

Dipeptides Containing Methionine Affects Gene Expressions Involved in Milk Protein Synthesis in Bovine Mammary Epithelial Cells

作　　者：陈璐[1] 常晨城 史彬林[1] 高民 赵艳丽[1] 闫素梅[1] 

机构地区：[1]内蒙古农业大学动物科学学院,呼和浩特010018 [2]内蒙古自治区农牧业科学院,呼和浩特010031

出　　处：《动物营养学报》2016年第12期4036-4043,共8页CHINESE JOURNAL OF ANIMAL NUTRITION

基　　金：国家奶业"973计划"项目(2011CB1008003)

摘　　要：本试验旨在研究含蛋氨酸(Met)二肽对奶牛乳腺上皮细胞(BMECs)内乳蛋白合成相关基因表达的影响。试验分3部分,均采用单因子完全随机试验设计,Met的添加浓度及培养时间分别为60μg/m L(0.402 mmol/L)、48 h。第1部分,培养液添加8种含Met二肽[蛋氨酸-蛋氨酸(P-Met-Met)、蛋氨酸-赖氨酸(P-Met-Lys)、蛋氨酸-色氨酸(P-Met-Trp)、蛋氨酸-苯丙氨酸(P-Met-Phe)、蛋氨酸-苏氨酸(P-Met-Thr)、蛋氨酸-异亮氨酸(P-Met-Ile)、蛋氨酸-亮氨酸(P-Met-Leu)、蛋氨酸-缬氨酸(P-Met-Val)],以不添加二肽为对照,测定BMECs乳蛋白合成相关基因(αs1-酪蛋白、β-酪蛋白、κ-酪蛋白、β-乳球蛋白、Ⅱ型小肽转运载体和氨肽酶氮)的表达量;第2部分,培养液添加8种与上述二肽对应的游离氨基酸(F-Met-Met、F-Met-Lys、F-MetTrp、F-M et-Phe、F-M et-Thr、F-M et-Ile、F-M et-Leu、F-M et-Val),以不添加游离氨基酸为对照,测定BM ECs乳蛋白合成相关基因的表达量;第3部分,用二肽等物质的量替代相应游离氨基酸,测定BMECs乳蛋白合成相关基因的表达量以及细胞内外氨肽酶含量。结果表明:P-Met-Met和P-M et-Lys组较对照组和其他二肽组上调了αs1-酪蛋白和β-酪蛋白基因的表达量,且P-M et-M et组优于P-Met-Lys组。F-Met-Met和F-Met-Lys组较对照组和其他游离氨基酸组显著提高了αs1-酪蛋白基因的表达量(P<0.05)。除P-Met-Val和P-Met-Leu组外,其他二肽替代游离氨基酸后均不同程度地提高了乳蛋白和Ⅱ型小肽转运载体基因的表达量,其中P-Met-Met表现出较好的促进效果。总之,含Met二肽等量替代对应的游离氨基酸能够促进乳蛋白基因的表达,其中尤以P-Met-Met的效果最好。The aim of this study was to investigate the effects of dipeptides containing methionine on gene expressions involved in milk protein synthesis in bovine mammary epithelial cells（BMECs）.The study consisted of three parts and adopted completely random single-factor designs.Concentration of methionine and incubation time were 60 μg/mL（0.402 mmol/L） and 48 h,respectively.Part 1,eight kinds of dipeptides[methioninemethionine（P-Met-Met）,methionine-lysine（P-Met-Lys）,methionine-tryptophan（P-Met-Trp）,methioninephenylalanine（P-Met-Phe）,methionine-threonine（P-Met-Thr）,methionine-isoleucine（P-Met-Ile）,methionine--leucine（P-Met-Leu） and methionine-valine（P-Met-Val）]were supplemented in culture medium,and culture medium without dipeptide supplementation was used as control;milk protein synthesis related geneα-casein（CSN1S1）,β-casein（CSN2）,κ-casein（CSN3）,β-lactoglobulin（LGB）,pep tide transporter 2（PEPT2） and aminopeptidase nitrogen（APN） expressions in BMECs were determined.Part 2,eight kinds of free amino acids（F-Met-Met,F-Met-Lys,F-Met-Trp,F-Met-Phe,F-Met-Thr,F-Met-Ile,F-Met-Leu and FMet-Val） corresponded with the above dipeptides,and culture medium without free amino acids supplementation was used as control;milk protein synthesis related gene expressions in BMECs were determined.Part 3,dipeptides containing methionine equimolarly substituted corresponding free amino acids;milk protein synthesis related gene expressions in BMECs and APA content inside and outside BMECs were determined.The results showed as follows：gene expressions of CSN1S1 and CSN2 were greater in P-Met-Met and P-Met-Lys groups than in other groups,and greater expressions were detected in P-Met-Met group than in P-Met-Lys group.Gene expressions of CSN1S1 was significantly increased in F-Met-Met and F-Met-Lys groups versus other groups（P〈0.05）.Except P-Met-Val and P-Met-Leu groups,dipeptides containing methionine substitution of corresponding free amino acids up-regulated the ex

关 键 词：奶牛 乳腺上皮细胞 乳蛋白 蛋氨酸 二肽 基因表达 

分 类 号：S823[农业科学—畜牧学]