军牧1号白猪、杜洛克猪、西藏小型猪和大白猪KIT毛色基因的基因型分析

毛色是猪的一个重要形态特征,KIT基因是控制猪毛色的主效基因。本研究利用PCR和PCR-SSCP方法,分析了军牧1号白猪、杜洛克猪、西藏小型猪和大白猪的KIT基因拷贝数和第17、18内含子突变位点的基因型,结果显示:军牧1号白猪和大白猪均为多拷贝,而西藏小型猪和杜洛克猪的KIT基因则为单拷贝;军牧1号白猪和大白猪的第17、18内含子突变位点上均检测到突变,而杜洛克猪和西藏小型猪均没有检测到突变。     

军牧1号白猪6号染色体抗病基因FUT1和RYR1的合并选择

FUT1和RYR1是猪6q11～12区段的抗病侯选基因,为探讨军牧1号白猪群体中2基因的关联度,随机选取177头军牧1号白猪,采用PCR-RFLP法检测2对等位基因频率和基因型频率、计算连锁不平衡参数。结果表明,军牧1号白猪群体中优势基因FUT1A的频率为0.395,RYR1T的频率为0.765,两者的连锁不平衡参数LD=0.010 7和相关系数r=0.093 6均接近于零,可判定两者不存在连锁关系。研究结果支持在军牧1号白猪群体中同时进行抗病基因FUT1和RYR1的合并选择。     

军牧1号白猪、杜洛克猪和藏猪的H-FABP 和LPIN1基因多态性分布

为探索H-FABP和LPIN1基因在不同猪种中的多态性分布情况,应用PCR-RFLP技术检测了61头军牧1号白猪、51头杜洛克猪和51头藏猪H-FABP和LPIN1基因的多态性分布。结果发现,军牧1号白猪、杜洛克猪和藏猪在H-FABP基因的Hinf Ⅰ多态性位点上均表现为单一的HH型,而Hea Ⅲ多态性位点上均表现出多态性,等位基因D的基因频率分别为0.1475、0.2255和0.7647,Msp Ⅰ多态位点上,军牧1号白猪表现为单一的aa型,杜洛克猪和藏猪则表现为多态性,等位基因A的基因频率分别为0.6078和0.4609。在LPIN1基因的Eco88 Ⅰ多态性位点上,杜洛克猪表现为单一的AA型,军牧1号白猪和藏猪表现为多态性,等位基因A的基因频率分别为0.4262和0.2059;在Bsh1236 Ⅰ多态性位点上,杜洛克猪表现为单一的TT型,军牧1号白猪和藏猪则表现为多态性,等位基因T的基因频率分别为0.7459和0.2059。     

不同品种猪抑肌素基因启动区的RFLP分析

瘦肉率是猪育种中重要的目标性状之一 ,其大小与骨骼肌的量密切相关。猪抑肌素基因是与瘦肉率有关的基因之一 ,本研究以大白、长白、杜洛克、民猪、三江白猪和军牧Ⅰ号为研究对象 ,采用限制性酶切片段生长度多态性 (RFLP)分子标记法对抑肌素基因的启动区进行了酶切多态性分析。结果表明 :大白、长白、杜洛克以等位基因T为主 :三江白猪和军牧Ⅰ号全部是TT型 ;民猪 3种基因型均有且频率近乎相等     

军牧1号白猪肉质主效基因的多态性检测

为检测军牧1号白猪的肉质主效基因多态性,应用RFLP技术分别检测了400头军牧1号白猪氟烷、酸肉以及心脏脂肪酸3个重要肉质基因的遗传变异情况。结果表明:在军牧1号白猪群中有氟烷基因存在,且3种基因型都有分布;在心脏脂肪酸基因的5′区的HfinⅠ和内含子2的HaeⅢ位点上,同样存在3种基因型的多态性;但内含子2的MSPⅠ位点和酸肉基因不存在多态性。     

军牧1号白猪、杜洛克猪和藏猪的氟烷基因和酸肉基因多态性分布

为了研究军牧1号白猪、杜洛克猪和藏猪氟烷基因和酸肉基因的多态性分布情况,试验采用PCR-RFLP方法对61头军牧1号白猪、51头杜洛克猪和51头藏猪的氟烷基因和酸肉基因多态性进行了检测。结果表明:军牧1号白猪的氟烷基因表现为单一的NN型;杜洛克猪的氟烷基因表现为多态性,等位基因N的频率为0.196 1,基因型分布符合哈代-温伯格平衡(χ2=3.033 9,P=0.081 5);藏猪的氟烷基因表现为单一的nn型。3个猪种的酸肉基因均表现为单一的rn/rn型。     

军牧1号白猪FUT1基因M307位点多态性研究

肠毒素大肠杆菌F18是引起断奶仔猪腹泻和仔猪水肿病的主要病原菌,α-1岩藻糖转移酶基因FUT1是控制大肠杆菌F18侵染猪小肠的受体蛋白表达的候选基因。采用PCR—RFLP方法对军牧1号白猪FUTl基因M307核苷酸G／A突变位点的多态性进行分析。结果表明,军牧1号白猪FUT1基因M307位点存在3种基因型,分布趋势为AG〉AA〉GG,等位基因A的频率为0．6048,为优势等位基因。X^2适合性检验结果表明,军牧1号白猪FUT1基因在M307位点上呈Hardy—Weinberg平衡状态。研究结果揭示军牧1号白猪有抵抗肠毒素大肠杆菌F18的遗传基础,在军牧1号白猪群体中可以通过标记辅助的方法培育对大肠杆菌F18具有抗性的新品系。     

中国人民解放军农牧大学成功培育出“军牧1号”新品系猪

中国人民解放军农牧大学成功培育出“军牧１号”新品系猪李铁檩，田柏若中国人民解放军农牧大学教授侯万文主持的国家自然科学基金委、总后军需部、吉林省科委重点支持的“军牧１号”瘦肉型新品系猪的选育，通过专家验收鉴定。专家一致认为，该品系猪日增重、产仔数、饲料...     

军牧1号白猪肉质主效基因的多态性检测分析

猪的肉质属于数量性状,受多个主效基因和候选基因的控制。为检测军牧1号白猪肉质主效基因多态性,本试验采用RFLP技术检测了400头军牧1号白猪氟烷基因(RYR1)、心脏脂肪酸结合蛋白基因(H-FABP)和酸肉基因(RN)3个重要肉质基因的多态性。群体遗传结构分析表明,军牧1号白猪群体中RYR1基因的N基因频率为0.908 3,n基因频率为0.091 7;心脏脂肪酸结合蛋白基因的5′区的HinfⅠ位点的H基因频率为0.688 8,h基因频率为0.311 2;H-FABP基因内含子-2HaeⅢ位点D基因频率为0.478 8,d基因频率为0.521 2;H-FABP基因内含子-2MSPⅠ位点不存在多态性;RN基因也不存在多态性。     

"军牧1号"断乳仔猪血液生理生化指标正常参考值

选用55日龄“军牧1号”断乳仔猪30头,测定了18项血液生理指标和10项血液生化指标。结果,“军牧1号”断乳仔猪与后备猪比较,有多项血液生理生化指标差异显著(<0.01),与其他同龄杂交品种猪比较,绝大多数指标基本一致。这些指标不仅能反映断乳仔猪的健康状况和生长发育规律,而且也是兽医临床诊断和防治的重要依据。     

阿勒泰羊羔羊MSTN mRNA表达的发育性变化

肌肉生长抑制素（MSTN）是一种骨骼肌生长发育的负调控因子.试验以不同生长阶段的阿勒泰羊羔羊为研究对象,采用实时荧光定量PCR技术测定了肌肉和脂肪组织中MSTN mRNA相对表达量.比较该基因在不同月龄阿勒泰羊羔羊肌肉和脂肪组织中的表达差异.结果表明：阿勒泰羊0～6月龄羔羊MSTN mRNA在肌肉和脂肪组织中均有表达.4月龄羔羊MSTN mRNA表达量在肌肉中最高,0～4月龄的表达量逐渐上升,4～6月龄逐渐下降.6月龄羔羊脂肪中的MSTN mRNA表达量最高.不同月龄阶段阿勒泰羊羔羊肌肉和脂肪MSTN mRNA表达量存在差异,这些差异可能会影响其生长发育和产肉性能等指标,这对进一步理解MSTN基因的调控作用奠定了基础.     

Expression of Myogenic Regulatory Factors in Myocardium and Skeletal Muscle at Different Fetal Stages

The topic of this research was to investigate the expression pattern of myogenic regulatory factors (MRFs) in the myocardium and skeletal muscle of sheep at different fetal stages,the fetuses of Tan sheep at 60 (E60),70 (E70),80 (E80) and 90 days (E90) of gestation were selected as the research objects,and the myocardium and skeletal muscle were collected.The histogenesis of myocardium and skeletal muscle during fetal development were observed by HE and oil red staining.The expression patterns of MRFs in myocardium and skeletal muscle during fetal development and the expression differences of MRFs between myocardium and skeletal muscle at the same stage were tested by Real-time quantitative PCR.The results of HE staining showed that the microstructure of myocardium and skeletal muscle was very different,myocardial fibers crisscross into a network with high density,which were more mature;the density of skeletal muscle fibers were low with large gaps,the number of fibers from E60 to E90 increased gradually,and the structure fiber bundles was very clear.The results of oil red staining showed that there were no fat droplets stained red in myocardium and skeletal muscle tissues,which means that these two tissues form E60 to E90 did not have fat differentiation.The results of Real-time quantitative PCR showed that the expression of MYOG,Myf5 and Myf6 genes in myocardium decreased continuously from E60 to E90 day,but there was no MYOD gene expression.The expression of MYOD,MYOG and Myf6 genes in skeletal muscle from E60 to E90 increased gradually,among which the level of MYOG gene was the highest,and the expression of Myf5 gene fluctuated periodically.The above results indicated that the skeletal muscle was at the stage of rapid development from E60 to E90,however,the myocardial tissue had been roughly formed,which led to the expression of MRFs in skeletal muscle tissue was much higher than that in myocardial tissue,and MYOG gene played an important role in maintaining the rapid development of skeletal muscle.     

生肌调节因子在绵羊不同胎儿期心肌和骨骼肌中的表达

本试验旨在探究生肌调节因子（myogenic regulatory factors，MRFs）在绵羊不同胎儿发育时期心肌和骨骼肌组织中的表达情况。选取妊娠60（E60）、70（E70）、80（E80）和90 d（E90）4个不同时期的滩羊胎儿作为研究对象，采集骨骼肌和心肌组织，通过HE和油红染色观察心肌和骨骼肌在胎儿发育过程中发生的组织形态学变化；通过实时荧光定量PCR研究绵羊胎儿发育过程中MRFs在心肌和骨骼肌组织中的表达规律以及同一胎儿期MRFs在心肌和骨骼肌中的表达差异。HE染色结果显示，心肌组织和骨骼肌组织的微观结构差异明显，心肌肌纤维密度大，纵横交错成网状，和骨骼肌相比发育的更加成熟；骨骼肌组织肌纤维密度小，间隙大，E60~E90肌纤维数量逐渐增加，肌纤维束结构清晰分明。油红染色结果显示，心肌和骨骼肌组织在4个时期均未出现被染成红色的脂滴，表明E60~E90两个组织均没有分化出脂肪。实时荧光定量PCR结果显示，E60~E90胎儿心肌组织中MYOG、Myf5和Myf6基因表达量持续降低，但是没有MYOD基因表达；E60~E90骨骼肌组织中MYOD、MYOG和Myf6基因表达量持续上升，其中MYOG基因表达水平最高，Myf5基因的表达发生周期性波动。以上结果表明，E60~E90胎儿骨骼肌正处于快速发育阶段，而心肌组织此时已大致成型。因此，骨骼肌组织中MRFs的表达量远远高于心肌组织，且MYOG基因对于维持骨骼肌的快速发育发挥了重要作用。     

Novel findings regarding Glut-4 expression in adipose tissue and muscle in horses--a preliminary report

One of the hallmarks of insulin resistance is a reduction in glucose transporter-4 (Glut-4) expression in adipose tissue but not in skeletal muscle. However, while Glut-4 has been demonstrated in skeletal and cardiac muscles in horses it has not been demonstrated in adipose tissue. The initial objectives of the present study were: (1) to test the hypothesis that Glut-4 expression would vary between selected key skeletal muscles; (2) to test the hypothesis that it would also vary between representative adipose tissue depots, and (3) to see whether expression would be greater in adipose tissue compared to muscle. Glut-4 expression was determined by Western blot using samples obtained from post mortem biopsies obtained from four muscles (gluteus medius, semitendinosus, heart, and diaphragm), and four adipose tissues (subcutaneous, retroperitoneal, mesenteric, and omental) in three horses. There were no differences (P>0.05) in Glut-4 protein expression between the muscles sampled. Likewise there were no differences (P>0.05) in Glut-4 protein expression between fat depots. There was a significant difference (P=0.03) when pooled means for Glut-4 expression in muscle (58.8+/-2.5 densitometry units) were compared with adipose tissue (115.8+/-15.7). This difference in Glut-4 expression in these two tissues with distinctly different metabolic reasons for taking up glucose may warrant further investigation to see if there are more pronounced differences in Glut-4 expression in muscle and adipose tissue in various populations of horses.     

肌肉生长抑制素对骨骼肌作用研究进展

肌肉生长抑制素(MSTN)是转化生长因子β超家族的成员之一,又称生长分化因子8。MSTN主要在骨骼肌中广泛表达,并可在心肌、脂肪、乳腺等多个组织中表达,其作用主要体现在抑制骨骼肌生长发育、诱发肌萎缩等方面。MSTN可以通过多种途径协同作用于骨骼肌,即通过激活TGF-β、p38MAPK、ERK1/2、JNK等信号途径以及抑制IGF-AKT、Wnt信号途径来抑制肌细胞增殖分化;通过调控AKT途径、泛素-蛋白水解酶系统、自噬溶酶体系统来影响骨骼肌蛋白的合成与分解;MSTN还参与了与骨骼肌生成相关的脂肪代谢及骨形成等生理活动。论文重点阐述MSTN在肌细胞增殖分化、肌蛋白合成与分解、脂肪代谢、骨骼发育等方面的作用机制,并对其应用前景进行展望,为相关科学研究提供参考。     

金茅黑鸡miR-206表达及靶基因预测分析

为了研究miR-206的组织表达分布及其在鸡骨骼肌生长发育中的表达规律，预测其可能的作用机制，本研究采集4周龄金茅黑鸡的心脏、肝脏、脾脏、肺脏、肾脏、胸肌、腿肌和腹脂8种组织及2、6、10、14、16周龄胸肌和腿肌组织，利用实时荧光定量PCR技术检测miR-206在8种组织及不同周龄胸肌和腿肌中的表达，利用生物信息学方法预测其靶基因并进行功能注释。结果显示，miR-206在公、母鸡胸肌和腿肌中表达量均极显著高于其他组织（P < 0.01），在腹脂、心脏、肝脏、脾脏、肺脏和肾脏中低表达，为鸡骨骼肌特异性表达miRNA；miR-206均在公、母鸡腿肌和胸肌组织生长早期（2周龄）表达最高，之后表达量逐渐下降。靶基因预测和功能分析发现，miR-206共有356个靶基因，其中21个与肌肉生成相关，多个靶基因已知参与调控肌肉生成，包括配对框7（paired box 7，Pax7）、胰岛素样生长因子1（insulin-like growth factor 1，IGF1）、脑衍生神经营养因子1（brain-derived neurotrophic factor 1，BDNF1）、视黄酸受体（retinoic acid receptor beta，RARB）和卷曲类受体7（frizzled class receptor 7，FZD7）基因。此外，发现miR-206靶基因富集到多条已知参与调控骨骼肌生成的信号通路，包括MAPK、Wnt、肌动蛋白骨架调控和黏着斑激酶信号通路。结合表达数据推测，miR-206可能通过靶向调控Pax7、IGF1、BDNF1、RARB、FZD7基因和MAPK、Wnt等信号通路参与调控鸡肌肉生成。本研究揭示了金茅黑鸡miR-206的组织表达分布及其在鸡骨骼肌生长过程中的表达规律，并预测了其调控骨骼肌生成的可能作用机理，为进一步研究miR-206在鸡肌肉生长发育中的作用机理和表达调控奠定了基础。     

牛心型α肌动蛋白基因的进化及表达研究

试验旨在对鲁西黄牛心型α肌动蛋白的进化及表达进行研究,为研究该基因的功能提供依据。试验采用生物信息学方法对心型α肌动蛋白的进化进行了分析,利用Western blotting和免疫荧光的方法分析了牛心型α肌动蛋白的表达模式。结果显示,心型α肌动蛋白除在鲁西黄牛心脏组织中有强表达外,在骨骼肌中也检测到该蛋白的表达。推测心型α肌动蛋白除在成体鲁西黄牛的心脏发育过程中起作用外,在骨骼肌发育过程中也起作用。     

Beta 3-adrenergic agonist up-regulates uncoupling proteins 2 and 3 in skeletal muscle of the mouse

Chronic stimulation of the beta3-adrenergic receptor (AR) in obese animals resulted in a reduced adiposity associated with an increased expression of thermogenic uncoupling protein (UCP)1 in adipose tissues. In this study, the mRNA expression of newly cloned UCP isoforms (UCP2 and UCP3) were examined in obese yellow KK and C57BL control mice. UCP2 mRNA was found in all tissues examined, with higher levels in adipose tissues and skeletal muscle of the obese mice. UCP3 mRNA was expressed in skeletal muscle, heart and brown adipose tissue similarly in the two mouse strains. Daily injection of a selective beta3-adrenergic agonist, CL316,243 (0.1 mg/kg), for 10 days resulted in a marked reduction of white fat pad weight and 1.8-4.8-fold increase in the mRNA levels of UCP2 and UCP3 in skeletal muscle of obese mice. No noticeable change in the UCP2 and 3 mRNA levels was found in brown and white adipose tissues. It was also found that CL316,243 injection produced a marked and sustained elevation of the plasma free fatty acid level. These results, together with our previous findings of the fatty acid-induced UCP expression in a myocyte cell line in vitro, suggest that the beta3-AR agonist-induced UCP expression in skeletal muscle may be mediated through the elevated plasma free fatty acids. It was also suggested that anti-obesity effect of beta3-AR agonists is attributable to increased thermogenesis not only by UCP1 but also by UCP2 and UCP3.     

Pathology of Murine Cytomegalovirus Infection in Newborn Mice. Muscle, Heart and Brown Fat Lesions

Newborn mice were inoculated intracerebrally with murine cytomegalovirus and studies were made of the pathological changes in the striate and cardiac muscle and brown fat. Widespread necrosis was seen in muscle and brown fat in the early stages of the infection. Necrotic lesions became calcified. By 56 days lesions were not resolved in the heart and brown fat but were completely resolved in skeletal muscle.     

Tissue and plasma activity of lactic dehydrogenase and creatine kinase in the horse

Lactic dehydrogenase, although widely distributed in most tissues, was more highly concentrated in skeletal muscle, cardiac muscle, kidney and liver. Isoenzyme patterns showed a selective concentration of LDH5 in skeletal muscle while in the heart LDH 1 and 2 were predominant. In contrast, creatine kinase was only present in substantial concentration in skeletal and cardiac muscle. The serum concentrationof both enzymes showed a wide range of activity.