新牧1号苜蓿两个抗逆相关基因启动子的克隆及分析

采用实时荧光定量PCR分析了新牧1号苜蓿（Medicago varia Xinmu 1）MvNHX1和MvDREB1基因在盐胁迫下的表达情况。此外,根据已获得的MvDREB1和MvNHX1基因序列设计特异引物,并以新牧1号苜蓿的基因组DNA为模板,克隆得到了这两个基因的启动子。利用生物信息学方法,分析这两个基因启动子的类型和结构,结果表明,MvNHX1和MvDREB1基因的启动子序列中均含有通用启动元件和上游调控元件,如CAAT框、TATA框、光响应元件、低温响应元件等,但部分响应元件的种类和数量不同。通过对两个基因启动子的克隆、分析及比较为进一步研究这两个基因的表达调控机制奠定了基础。     

Effect of dietary fish oil intake on ubiquitin ligase expression during muscle atrophy induced by sciatic nerve denervation in mice

Dietary fish oil intake improves muscle atrophy in several atrophy models however the effect on denervation‐induced muscle atrophy is not clear. Thus, the aim of this study was to investigate the effects of dietary fish oil intake on muscle atrophy and the expression of muscle atrophy markers induced by sciatic nerve denervation in mice. We performed histological and quantitative mRNA expression analysis of muscle atrophy markers in mice fed with fish oil with sciatic nerve denervation. Histological analysis indicated that dietary fish oil intake slightly prevented the decrease of muscle fiber diameter induced by denervation treatment. In addition, dietary fish oil intake suppressed the MuRF1 (tripartite motif‐containing 63) expression up‐regulated by denervation treatment, and this was due to decreased tumor necrosis factor‐alpha (TNF‐α) production in skeletal muscle. We concluded that dietary fish oil intake suppressed MuRF1 expression by decreasing TNF‐α production during muscle atrophy induced by sciatic nerve denervation in mice.     

不同日龄仔猪骨髓组织抗菌肽Protegrin-1mRNA的表达

分别于出生当天、3、14、23和28日龄随机屠宰杜×长×大三元杂交公猪4头，采集股骨骨髓组织。用一优化的RT—PCR方法，以18S rRNA作内标，定量分析不同日龄仔猪骨髓组织抗菌肽Protegrin-1（PG-1）mRNA表达的差异。结果表明，不同日龄仔猪骨髓组织PG-1mRNA相对丰度有明显的差异。出生时最低，随着日龄的增加，其表达显著增加。     

热加工方式对牛乳过敏原αs1-酪蛋白二级结构和抗原性的影响

为探究热加工方式对牛乳过敏原αs1-酪蛋白构象和抗原性的影响,利用间接竞争酶联免疫吸附测定方法、 免疫印迹方法分析不同加热条件下αs1-酪蛋白免疫原性的变化,进而通过8-苯胺-1-萘磺酸荧光探针和圆二色谱分 析其二级结构变化,初步揭示热处理调控过敏原αs1-酪蛋白抗原性的机制。结果表明：在80 ℃、60 min,90 ℃、 10 min,90 ℃、60 min条件下热处理后,αs1-酪蛋白中α-螺旋结构含量显著低于未加热αs1-酪蛋白,在70 ℃、 20 min,80 ℃、20 min,90 ℃、20 min条件下热处理后,αs1-酪蛋白中无规卷曲含量显著增加,70～100 ℃加热 20 min条件下表面荧光强度最强,其他温度-时间条件下二级结构含量变化不显著;αs1-酪蛋白构象的变化导致αs1-酪 蛋白的抗原性显著降低,间接竞争酶联免疫吸附测定显示,在70～100 ℃加热20 min条件下,αs1-酪蛋白的抗原残留 量均较高,而免疫印迹方法显示不同温度-时间条件下αs1-酪蛋白仍具有免疫反应特性,建议进一步通过动物实验揭 示热处理调控αs1-酪蛋白抗原性的机制。     

Effect of dipeptide on intestinal peptide transporter 1 gene expression: An evaluation using primary cultured chicken intestinal epithelial cells

Peptide transporter 1 (PepT1) is a transporter responsible for absorbing dipeptide and tripeptide in enterocytes and is upregulated by dipeptide in mammals. It has not been certain whether intestinal PepT1 expression is responsive to dipeptides in chickens because of the lack of in vitro study using the cultured enterocytes. This study established a primary culture model of chicken intestinal epithelial cells (IECs) in two-dimensional monolayer culture using collagen gel by which the response of chicken PepT1 gene expression to dipeptide stimuli was evaluated. The cultured chicken IECs showed the epithelial-like morphology attached in a patch-manner and exhibited positive expression of cytokeratin and epithelial cadherin, specific marker proteins of epithelial cells. Moreover, the chicken IECs exhibited the gene expression of intestinal cell type-specific marker, villin1, mucin 2, and chromogranin A, suggesting that the cultured IECs were composed of enterocytes as well as goblet and enteroendocrine cells. PepT1 gene expression was significantly upregulated by synthetic dipeptide, glycyl-l-glutamine, in the cultured IECs. From the results, we herein suggested that dipeptide is a factor upregulating PepT1 gene expression in chicken IECs.     

中国地方绵羊群体TYRP1基因遗传变异研究

本研究旨在了解酪氨酸酶相关蛋白1（tyrosinase related protein 1,TYRP1）基因在中国地方绵羊群体内的遗传变异,以及TYRP1基因突变与不同毛色表型绵羊群体的相关性。通过直接测序法和PCR-RFLP技术对10个中国地方绵羊群体进行单核苷酸多态性（SNP）检测,利用Beagle、PLINK和POPGENE等软件对突变位点数据进行单倍型构建、连锁不平衡分析和遗传变异研究。突变位点检测结果表明,在绵羊TYRP1基因内识别了13个SNPs,其中位于TYRP1基因外显子上的10个SNPs位点,除个别位点在大尾寒羊、中国美利奴羊和岷县黑裘皮羊中没有发生突变外,其他突变位点在所有绵羊品种中均出现不同程度变异,说明中国地方绵羊群体具有较高的遗传多样性。单倍型分析结果表明,所有样本中共有42个单倍型,优势单倍型0000000000（245/918）、0100000001（91/918）在所有绵羊群体中均存在,除单倍型0101100000（93/918）在中国美利奴羊中没有出现,单倍型0001000001（69/918）在岷县黑裘皮羊、哈萨克羊群体中没有出现外,在其他群体中均存在。连锁分析结果表明,10个SNPs在所有样本中均存在2个连锁模块。群体遗传变异分析表明,中国地方绵羊群体具有较高水平的群体内遗传变异,各绵羊品种间存在明显的遗传分化模式,且各品种遗传关系与其品种传统分类结果基本一致。本研究为进一步研究TYRP1基因对绵羊毛色遗传性状的影响提供了参考依据。     

中国荷斯坦牛GlyCAM1基因遗传多态性的研究

以273头中国荷斯坦牛为研究对象,利用CRS—PCR、PCR—SSCP及DNA测序技术检测了GlyCAM1基因外显子3、内含子3的遗传多态性。结果表明：GlyCAM1基因分别在外显子3和内含子3的第2081（A／C）、2417（C／T）位存在突变,2个位点的等位基因频率A／B分别为0．7525,0．2475和0．9046,0．0954;经菇。适合性检验,中国荷斯坦牛内含子3的突变达到Hardy—Weinberg平衡状态（P〉0．05）,但其外显子3的突变未达到Hardy—Weinberg平衡状态（P〈0．05）。     

Immunopathology of <Emphasis Type="Italic">Dirofilaria immitis</Emphasis> Infection

Heartworm disease caused by Dirofilaria immitis affects canine and feline hosts, with infections occasionally being reported in humans. Studies have shown that both dirofilarial antigens and those derived from its bacterial endosymbiont Wolbachia, interact with the host organism during canine, feline and human infections and participate in the development of the pathology and in the regulation of the host’s immune response. Both innate and acquired immune responses are observed and the development of the acquired response may depend on the host and, or on its parasitological status. This review aims at illustrating current research on the role of both D. immitis and Wolbachia, in the immunology and immunopathology of dirofilariosis.     

DIPHOSPHONATE TREATMENT OF A PRIMARY OSTEOSARCOMA IN A DOG: A CASE REPORT

The following sequence of treatments was administered to a Saint Bernard dog with a primary distal right radius osteosarcoma: 54 days of daily disodium 1-hydroxyethylidenediphosphonate (HEDP) subcutaneous injections; 53 days of HEDP per os ; one ³²P-HEDP intravenous injection. During the pretreatment period, there was an extensive increase in calcific tumor growth and osteoblastic proliferation. After the subcutaneous HEDP treatment, almost complete tumor necrosis was seen. After the oral HEDP treatment, only the deepest tumor portion contained active osteoblasts, calcific growth of the tumor was completely blocked, and uptake of ^99mTc-Sn-HEDP was reduced to one fourth of the pretreatment uptake. After a single ³²P-HEDP dose, large areas of tumor necrosis were evident histopathologically. However, subsequent resumption of cellular activity occurred in the tumor, and the uptake of ^99mTc-Sn-HEDP increased to pretreatment values. These data suggest that systemically administered HEDP should be studied further for its possible therapeutic potential in the treatment of osteosarcoma and indicate a need for further study of ³²P-HEDP or possibly ³³P-HEDP.     

mRNA差异显示技术、PCR技术及其在动物营养研究中的运用

21世纪将是生命科学的世纪。当前,世界各国都将分子生物学纳入本国科技发展的重点。分子生物学技术的迅速发展为营养科学探索必需营养缺陷的分子基础提供了强有力的实验工具。本文旨在对mRNA差异显示技术、PCR技术等两种最常用的生物技术手段的原理、特点及其在动物营养研究中的应用作一综述。