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101.
【目的】寻找与文昌鸡繁殖性能相关的遗传标记。【方法】以促卵泡素受体(FSHR)基因作为影响鸡繁殖性状的候选基因,采用PCR-SSCP技术结合测序分析,对FSHR基因所有外显子及部分内含子区域进行单核苷酸多态性(SNPs)检测,收集文昌鸡繁殖性能指标,分析FSHR基因多态性与繁殖性状的关系。【结果】共发现4个区域存在SNPs位点,分别为:区域4中exon 4编码区43bp处的T→C突变,但没有导致翻译后氨基酸序列的改变;区域2中exon 2编码区5′端-49bp处的C→T突变;区域6中exon 6编码区3′端+12bp处的A→G突变;区域9中exon 8编码区3′端+38bp处的G→T突变。对以上4个区域不同基因型与繁殖性状的相关性分析表明,文昌鸡FSHR基因第4外显子呈现的3种基因型(CC/CD/DD)多态性,与文昌鸡300日龄产蛋数及平均联产天数显著相关(P<0.05)),而且CD杂合基因型的300日龄产蛋数及平均联产天数显著高于其他基因型(P<0.05)。【结论】FSHR基因可作为影响文昌鸡产蛋数的候选基因。 相似文献
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甘蓝两种SRK短截蛋白的体外表达及其与THL1作用检测 总被引:1,自引:0,他引:1
为探明S–位点受体激酶(SRK)上与类硫氧还蛋白1(THL1)作用的氨基酸区域以及两者间作用方式,依据SRKE1上功能域分布构建了两种SRKE1短截体原核表达质粒pGEX-SRKE1A和pGEX-SRKE1B,分别在大肠杆菌BL21中获得了可溶性表达。通过体外孵育检测蛋白质相互作用的方法对SRKE1A、SRKE1B与THL1相互作用进行了检测,结果表明SRKE1A和SRKE1B均可与THL1结合,明确了THL1与SRK相互作用并不依赖于SRK激酶活性。两类SRK等位序列间比对结果表明Cys在两类SRK间的保守性存在明显差异,推测两类SRK材料亲和性的差异可能与Cys保守性不同有关。 相似文献
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AIM: To investigate the protective effect of recombinant SCR15-18 domain of human complement receptor type 1 (CR1-SCR-15-18) on intestinal ischemia and reperfusion in a rat model. METHODS: Sprague-Dawley rats were randomly divided into 3 groups: sham operation(SO) group, ischemia and reperfusion (I/R) group and CR1-SCR15-18 treatment group. The superior mesenteric artery of the rats was clamped for 30 min followed by 60 min of reperfusion. PBS alone or CR1-SCR15-18 protein (30 mg/kg) in PBS was intravenously administered 5 min before reperfusion. Intestinal vascular permeability, myeloperoxidase (MPO), malondialdehyde (MDA) and superoxide dismutase (SOD) were measured. The histopathological changes of intestinal mucosa were examined by HE staining and complement 3 was detected by immunohistochemical analysis. RESULTS: Compared with SO group, the vascular permeability, the activity of MPO and the content of MDA in I/R group were significantly increased, and the activity of SOD was decreased. HE staining demonstrated that I/R induced severe intestinal histological damages and the increased amount of complement 3 and its derivates were deposited in the necrosis area. Compared with I/R group, the vascular permeability, the activity of MPO and the content of MDA were decreased and the activity of SOD was significantly increased in CR1-SCR15-18 treatment group. CR1-SCR15-18 also significantly attenuated intestinal histological injury, and reduced the deposition of complement 3 and its derivates in the necrosis zone. CONCLUSION: sCR1-SCR15-18 protein exerts a protective effect against intestinal I/R injury in rats, possibly by inhibiting the activation of complement. 相似文献
104.
It has been widely appreciated that animal cells rely on the mechanism of regulatory volume decrease(RVD) after swell in a hypotonic environment. Activation of K channels is crucial in the process of self-protection. There are a characterized increase in cytoplasmic Ca and a decrease in pH in the process of RVD in many cell types. Ca entry via transient receptor potential(TRP) channel is crucial for the cytoplasmic Ca increase, which in turn induces the decrease in pH.The increase in cytoplasmic Ca and decrease in pH activate or inhibit the activity of K channel, respectively. In this review, the regulatory network at cellular level between cytoplasmic Ca and pH, and the modulation of K channels by Ca and pH in the process of RVD are discussed. 相似文献
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为研究病毒与机体的相互作用,本研究参考GenBank中鸡Toll样受体21 (ChTLR21)的基因序列设计实时定量PCR特异性引物,以鸡核糖体蛋白L4 (RPL4)为内参基因,建立检测ChTLR21 mRNA相对转录水平的实时定量PCR方法,分析ChTLR21在禽传染性喉气管炎病毒(ILTV)感染的鸡胚成纤维细胞(CEF)中和感染SPF雏鸡免疫器官脾脏、法氏囊和胸腺组织中的转录水平.结果显示:ILTV感染CEF后2h、4h、8h和18h时间点ChTLR21 mRNA转录水平分别为未感染对照细胞的1 540.53、0.98、1.19和3.70倍.但仅在ILTV感染2h时引起ChTLR21转录水平升高,与对照组相比差异显著(P<0.05).ILTV感染SPF雏鸡后6h、24 h和30 h脾脏中ChTLR21 mRNA转录水平分别为未感染对照的56.34、59.85和3.61倍;法氏囊中分别为0.03、25.98和3.08倍;胸腺中分别为2.52、50和7.32倍.在感染初期,脾脏中ChTLR21转录量显著升高,随后有所降低,但均高于未感染对照(p<0.05);法氏囊中仅在感染6h时呈显著抑制(p<0.01);胸腺中呈波动性转录水平升高,但与对照组无统计学差异(p>0.05).本研究证明ChTLR21参与了鸡体对ILTV感染的应答,并在体内外感染模型中呈现不同的表达规律. 相似文献
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X.?Cui R.?HarlingEmail author 《European journal of plant pathology / European Foundation for Plant Pathology》2005,111(4):327-339
Quorum sensing is a bacterial communication mechanism by which bacteria sense their own population size and couple specific gene expression to cell density. In Gram-negative bacteria, the most commonly used quorum sensing signals are N-acyl homoserine lactones (AHLs). It is now apparent that many pathogenic bacteria employ quorum sensing to control premature expression of virulence factors. This control is thought to decrease the likelihood that the plant host would detect the pathogens presence and activate its defense system. Novel strategies that target bacterial quorum sensing systems in order to control plant bacterial diseases are discussed. 相似文献