促黄体素受体研究进展

促黄体素 (L uteinizing hormone re-cepter,L HR)是哺乳动物生殖调控的重要激素 ,生理作用是通过其受体介导的。近几年来 ,L HR的研究已取得了重大的进展。文章对 L HR结构、受体的配体结合域、激素 -受体相互作用、信号转导与 G蛋白偶联、受体糖基化及脱敏、受体基因结构与调节、受体表达及受体突变对生殖机能的影响等方面进行了综述 ,以促进 L HR在生殖调控和疾病治疗中的进一步研究     

瘦素受体研究进展

瘦素（Leptin）是肥胖基因（obese gene,ob基因)的蛋白质表达产物,是一种主要由脂肪细胞分泌的蛋白质,其作用主要是调节动物的能量代谢和生殖活动。与其它激素一样,Leptin必须与其受体特异性结合后才能发挥其生理功能。作者从瘦素受体（Leptin receptor或OB-R）角度出发,探讨了OB-R的结构、组织分布、生物学功能及Leptin与OB-R间的信号传导,为进一步研究Leptin的作用提供参考。     

杯状病毒受体研究进展

杯状病毒科(Caliciviridae)的病毒是一类多样性的病毒,具有广泛的宿主和组织趋向性。对于其受体的研究,近年来取得了一定的进展。鉴定的受体分子主要集中于两类,一类是碳水化合物,包括组织血型抗原(HBGAs)、唾液酸和硫酸乙酰肝素;另一类是细胞蛋白,如连接黏附分子-A(JAM-A),一种分子质量为105 ku的膜蛋白等。此外,病毒与宿主受体相互识别的分子机制也取得了进展,这些研究对于深入了解病毒与宿主间的相互关系及有针对性地进行抗病毒药物、疫苗的研制具有重大意义。     

雌激素受体研究进展

雌激素(E)是由内分泌腺产生的一种类固醇性激素,与人类的生殖、骨骼以及大脑的发育息息相关。雌激素受体(ER)是类固醇激素受体超家族的成员之一,是一种配体依赖性转录因子,它与雌激素特异性结合,通过雌激素应答元件(EREs)来调节基因的转录。1雌激素受体基本结构与分类1.1雌激素     

病毒受体研究进展

病毒通过与宿主易感细胞表面的特异性受体结合而启动其复制过程。宿主的组织及细胞表面特定受体是决定病毒入侵途径、扩散方式及决定宿主发病特点的主要因素：因此，开展对病毒受体的研究具有重要意义。从受体角度阐明病毒入侵机制，是预防和治疗病毒性疾病的药物及疫苗研发重要领域。     

性腺外FSH受体和LH受体表达研究进展

雌性动物的性腺是卵巢,性腺外的生殖组织器官主要包括:输卵管、子宫颈、子宫肌层等,其中子宫是内分泌器官,除有局部内分泌功能外,还可能对下丘脑-垂体-卵巢轴有调节作用.促卵泡素(FSH)和促黄体素(LH)的生理功能是通过其FSHR、LHR来介导的,其受体在性腺和性腺外均有表达.本文主要对雌性性腺外生殖组织器官上两种受体的表达加以综述.     

嗅觉受体研究进展

在人和动物的生命过程中,嗅觉起着重要作用。嗅觉受嗅觉受体基因调控。嗅觉受体基因的缺失能引起特异性的嗅觉分辨力下降或缺失。     

降钙素受体研究进展

降钙素由甲状旁腺分泌，和甲状旁腺激素等一起调节体内的钙平衡。关于其结构、生理作用和药理效应等方面的研究有了很大进展，但关于降钙素受体的研究一直很缓慢。随着分子生物技术的发展．人们对降钙素受体的研究在近几年取得了很大进展，特别是对其cDNA的克隆、测序和表达。本文就降钙素受体的研究概况、结构、调节和在动物上的最新研究及应用进行了综述。     

Cloning of the growth hormone receptor and its muscle-specific mRNA expression in black Muscovy duck (Cairina moschata)

1. The cDNA sequence of the growth hormone receptor (GHR) from the black Muscovy duck was obtained and compared to the mRNA expression of growth hormone (GH) in the breast and leg muscles during 2–13 weeks of age using quantitative RT-PCR.

2. The cDNA sequence of the Muscovy duck GHR gene is 1903 bp in length, with an 1830 bp coding region that encodes 609 amino acids. It exhibits > 92.9% homology with the poultry GHR cDNA and amino acid sequences.

3. Overall, GHR mRNA expression was the highest at 2 weeks and the lowest at 13 weeks of age, exhibiting different profiles in different muscles. In the breast muscles, the GHR mRNA level declined sharply at 2–4 weeks, maintained at a plateau at 4–10 weeks and decreased slightly at 10–13 weeks. In the leg muscles, a gradual and slow decrease was observed during the whole period of 2–13 weeks.

4. Robust extra-pituitary GH mRNA expression was detected in the muscles and the expression profile was highly correlated with that of GHR mRNA, in contrast to the inverse correlation between the pituitary GH and tissue GHR levels shown previously.

5. These data suggest that the locally synthesised GH in the muscles, rather than the pituitary GH, is more closely associated with GHR and may be more critical for the regulation of muscle growth and contribute to the tissue-specific effects of GH.

     

硬脂酰辅酶A去饱和酶-1基因表达及其与鸭肉质和血清生化指标的相关性分析

试验分别在基础日粮中添加含4%亚油酸和4%二十碳五烯酸(EPA)对樱桃谷鸭进行饲养,检测4、6、8和10周龄樱桃谷鸭硬脂酰辅酶A去饱和酶-1(SCD-1)基因mRNA表达丰度,分析其表达与10周龄鸭肉质和血清生化指标的相关性。实时荧光定量PCR结果显示,亚油酸和二十碳五烯酸均能显著降低各周龄SCD-1基因在鸭肝脏、脂肪和胸肌中的mRNA表达水平(P0.05),说明亚油酸和二十碳五烯酸均具有抑制SCD-1基因转录的功能,亚油酸组鸭SCD-1基因mRNA表达水平与二十碳五烯酸组相比未达到显著差异(P0.05);相关性分析结果显示,鸭SCD-1基因mRNA表达丰度与10周龄鸭血清中甘油三酯(TG)、总胆固醇(TCHO)、高密度脂蛋白(HDL)和低密度脂蛋白(LDL)呈显著正相关(P0.05),与各常规肉质指标的相关性未达到显著水平(P0.05),表明SCD-1基因在鸭的脂质代谢过程中发挥着重要的调控作用。     

籽鹅和莱茵鹅MSTN和MyoG基因表达及其与屠宰性状的相关分析

本研究旨在探讨肌肉生成抑制素(myostatin,MSTN)和肌细胞生成素(myogenin,MyoG)基因对鹅骨骼肌生长发育的影响。试验以莱茵鹅和籽鹅为研究对象,采用实时荧光定量PCR方法测定MSTN、MyoG基因在籽鹅和莱茵鹅胸肌、腿肌中的差异表达情况,运用统计软件对基因表达情况与屠宰性状间的相关性进行分析。结果显示,莱茵鹅胸肌重和胸肌率极显著高于籽鹅(P<0.01),籽鹅胸肌MSTN、MyoG mRNA表达量极显著高于莱茵鹅(P<0.01);在腿肌中,籽鹅MSTN mRNA表达量极显著低于莱茵鹅(P<0.01),籽鹅与莱茵鹅MyoG mRNA表达量间无显著差异(P>0.05)。同一品种MSTN mRNA表达水平也存在差异,在籽鹅胸肌和腿肌中表达量存在极显著差异(P<0.01);在莱茵鹅胸肌和腿肌中表达量存在显著差异(P<0.05)。就MyoG mRNA而言,在籽鹅和莱茵鹅胸肌和腿肌中表达量存在极显著差异(P<0.01)。MSTN基因表达与屠宰性能相关性分析表明,胸肌中MSTN mRNA表达量与活重、胸肌重和胸肌率呈极显著负相关(P<0.01);胸肌和腿肌中MyoG mRNA表达量与活重呈极显著正相关(P<0.01)。说明MSTN和MyoG基因可能对肌肉生长分别起正负调控作用。     

Expression of MSTN and MyoG Genes in Zi and Rhine Goose and their Correlation with Carcass Traits

The aim of this study was to investigate the effects of MSTN and MyoG genes on goose skeletal muscle growth.In this study,MSTN and MyoG genes expression were detected in breast and leg muscle of Zi and Rhine goose by Real-time PCR,and the correlations between genes expression levels and carcass traits were investigated.The results showed that the breast muscle weight and breast muscle rate of Rhine goose were extremely significant higher than Zi goose (P<0.01).MSTN and MyoG mRNA expression in breast muscle of Zi goose were significantly higher than that of Rhine goose,and the mRNA level of MSTN in leg muscle of Rhine was extremely significant higher than that of Zi goose (P<0.01),there was no significant difference of MyoG mRNA between Zi goose and Rhine goose (P>0.05).There was extremely significant difference between MSTN mRNA expression in breast muscle and leg muscle of Zi goose (P<0.01).MSTN mRNA expression in leg muscle was significantly higher than that of breast muscle of Rhine goose (P<0.05).There was extremely significant difference between MyoG mRNA expression in breast muscle and leg muscle of Zi goose and Rhine goose (P<0.01).There was a extremely significant negative correlation between MSTN mRNA expression in breast muscle with body weight,breast muscle weight and breast muscle percentage (P<0.01).There was a extremely significant positive correlation between MyoG mRNA expression in breast muscle and leg muscle with body weight (P<0.01).MSTN and MyoG gene might have positive and negative regulation effect on muscle growth.     

Ⅰ型雏鸭肝炎病毒侵染后鸭组织中ALB基因表达的分析

检测Ⅰ型雏鸭肝炎病毒侵染后ALB基因mRNA以及ALB蛋白分别在肝脏、脾脏、肺脏、肾脏、大脑、小脑、腿肌和胸腺等组织中的相对表达量和含量并分析其意义。分别利用实时荧光定量RT-PCR技术和ELISA法检测ALB基因在易感组、抗病组和对照组各组织中mRNA的表达量以及ALB蛋白含量。总体而言,除腿肌外,ALB基因mRNA在易感组中的表达量极显著低于对照组和抗病组(P<0.01),抗病组显著或极显著低于对照组(P<0.01或P<0.05);各处理组间,肝、小脑和胸腺中ALB蛋白含量与ALB基因mRNA相对表达量规律一致,在其他组织中,各处理组间ALB蛋白含量差异均不显著(P>0.05)。RT-PCR与ELISA的结果比较可见,两者在肝脏、胸腺、小脑等与雏鸭肝炎病直接相关的指示性组织中表现一致。本试验研究结果,进一步揭示了ALB基因为Ⅰ型雏鸭肝炎病的抗性基因,与前期抑制性消减杂交法得到的结果一致,其表达量的变化可以作为区分易感鸭和抗病鸭的标志。     

北京鸭胸肌厚度与屠体性能指标的相关关系研究

先后进行两次饲养试验和屠宰试验研究肉鸭胸肌厚度和胸肌质量、胸肌率的相关关系。试验1饲养大体型A品系和小体型B、C品系的北京鸭各150只至7周龄,每个品系随机选取8只公鸭和8只母鸭进行屠宰试验。探索超声波扫描技术活体测定北京鸭胸肌厚度的方法,建立北京鸭胸肌厚度与胸肌质量、胸肌率等指标的相关关系。试验2饲养B系肉鸭1900只至7周龄,随机选取100只公鸭和100只母鸭进行屠宰试验,测定胸肌厚度和主要屠体指标,进行相关分系。结果:超声波测定北京鸭的胸肌厚度,图象清晰;大体型品系北京鸭7周龄的胸肌厚度达到22.3mm,小体型为16.2和16.3mm。胸肌厚度与胸肌质量、胸肌率的相关系数分别为0.6328(P<0.01)、0.4721(P<0.01),均达到极显著水平。结果表明,超声波扫描技术能够准确地测定北京鸭的胸肌厚度;北京鸭的胸肌厚度与胸肌产量、胸肌率存在显著的正相关关系。     

泛酸干预脂肪甘油三酯脂肪酶和长链脂酰辅酶A合成酶1基因表达对鹅生长和脂类代谢的反向调控

本试验通过研究泛酸对5~16周龄五龙鹅肝脏中脂肪甘油三酯脂肪酶(ATGL)和长链脂酰辅酶A合成酶1(ACSL1)基因表达的影响,并分析其与生长性能、屠宰性能、肉品质的相关性,旨在从分子角度确定鹅饲粮中泛酸的适宜添加水平。选择5周龄五龙鹅360只,随机分为6个组,每个组6个重复,每个重复10只鹅。各组饲粮中泛酸添加水平分别为0(对照)、5、10、20、40、80 mg/kg。试验期12周。结果表明:1)随着饲粮泛酸添加水平的提高,ATG L mRNA的表达量呈现先降低后升高的趋势,ACSL1 mRNA表达量呈现先升高后降低的趋势。由回归方程得出,当饲粮泛酸添加水平为13.86 mg/kg时,ATGL mRNA表达量最低;当添加水平为22.07 mg/kg时,ACSL1 mRNA表达量最高。2)与对照组相比,饲粮泛酸添加水平为10~20 mg/kg时极显著提高了五龙鹅的体重和平均日增重(P0.01),同时极显著降低料重比(P0.01)。3)ATG L mRNA表达量与胸肌率、腿肌率、屠宰率、半净膛率和全净膛率呈负相关;A CSL1 mRNA表达量与胸肌率、腿肌率、屠宰率、半净膛率和全净膛率呈正相关;二者mRNA表达量与腹脂率均呈负相关。4)ACSL1 mRNA表达量与红度和滴水损失显著相关(P0.05)。5)A TG L mRNA表达量与血清脂类代谢各项指标呈正相关;A CSL1 mRNA表达量与血清脂类代谢各项指标呈负相关。由此表明,ATGL和ACSL1 mRNA表达量对鹅机体生长速度、屠宰性能和脂类代谢呈同步反向调控机制;从ATGL和ACSL1 mRNA表达量优势分析,建议5~16周龄鹅饲粮中泛酸适宜添加水平为13.86~22.07 mg/kg。     

Myostatin in black Muscovy duck (Cairina moschata): full-length cDNA cloning and age-dependent mRNA expression compared with IGF-I

1. Insulin-like growth factor-I (IGF-I) and myostatin (MSTN) are a pair of critical positive and negative growth regulators. The aim of the current study was to examine the age-dependent and muscle-specific expression of IGF-I and MSTN mRNAs in black Muscovy ducks in order to understand their roles in regulating the postnatal muscle growth of domestic ducks.

2. The full-length cDNA of the black Muscovy duck MSTN gene was cloned and the age-dependent mRNA expression profile was compared with that of the IGF-I mRNA in skeletal muscles.

3. The cDNA sequence of the MSTN gene was 1128 bp in length and encodes 375 amino acids, with more than 94.9% homology with poultry MSTN genes, and 83.0–92.0% homology with that of human and mammals (accession: KR006339.1).

4. The IGF-I and MSTN mRNA expression exhibited opposite trends in age-dependency and in different muscles: IGF-I mRNA level was high in the early postnatal stage and low in the late mature stage, corresponding positively to growth; while the MSTN mRNA was low in the early stage, increased gradually and reached the highest level in mature muscles, and was negatively related to muscle growth. In the breast muscles, IGF-I mRNA was much higher than in the leg muscles; the opposite effect was seen in MSTN mRNA.

5. These data suggest that the relative expression levels of IGF-I and MSTN are essential determinants in the temporal and muscle-specific regulation of postnatal skeletal muscle growth in Muscovy duck and possibly in other poultry species as well.

     

Influence of recombinant duck follistatin protein on embryonic muscle development and gene expressions

Follistatin (FST) acts as a positive regulator of muscle development by inhibiting the activities and expression of myostatin. The recombinant duck FST protein was injected into hatching eggs and was also added to the medium of duck myoblast to study its role on duck embryonic muscle development and gene expressions. Duck embryo weight increased 3.49% (p > 0.05) in FST treatment group as compared with control group, but minor effects were found on leg or breast muscle weights of ducklings at 2 days post‐hatching (p > 0.05). Relative expression of Pax7 was upregulated in both leg and breast muscle tissues (p < 0.05), while MyoD was only upregulated in leg muscle (p < 0.05), and Myf5 was only upregulated in breast muscle (p < 0.05). Relative expression of myostatin was downregulated in both muscle tissues researched (p < 0.05). In vitro studies also showed some maker genes relevant to protein synthesis and degradation, cells’ proliferation and differentiation had significant changes in myoblasts after treated with FST. These results suggested that in ovo feeding of recombinant FST protein to duck hatching eggs had an effect on duck embryo development but have less roles on the duck embryonic muscle development.     

不同饲养模式对嘉积鸭肌肉品质的影响

为了研究不同饲养模式(传统饲料+放养、传统饲料+网床饲养、商业饲料+网床饲养、自制饲料+网床饲养)对嘉积鸭肌肉品质的影响,将1 200只1周龄嘉积鸭随机分为4组,每组设3个重复,13周龄末结束试验.对比4种模式下嘉积鸭的肉质物理指标、营养成分以及感官评分等.结果 表明:(1)传统饲料+放养模式嘉积鸭胸肌氨基酸总量显著高...