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491.
以雌性籽鹅脑垂体的总RNA为模板,利用特异性引物通过RT-PCR扩增获得长为363 bp的籽鹅促卵泡激素α亚基的cDNA片段,将扩增的促卵泡激素α亚基基因片段克隆至pMD18-T载体后进行测序。将测序结果与鸡、鹌鹑、火鸡、鼠、羊、牛等多种禽类和哺乳动物的该基因核苷酸序列及推导的氨基酸序列进行同源性分析。结果表明,这些物种促卵泡激素α亚基基因序列具有较高的保守性,其中与鸡、鹌鹑、火鸡的核苷酸同源性最高,均为95.9%,推导的氨基酸序列与鸡、鹌鹑、火鸡的同源性最高,均为97.5%。为了对克隆的籽鹅促卵泡激素α亚基基因功能研究提供基础,将籽鹅促卵泡激素α亚基基因克隆至pET-32a(+)原核表达载体。  相似文献   
492.
KAP6基因家族成员在胚胎期山羊皮肤中的表达   总被引:1,自引:0,他引:1  
为研究KAP6家族成员在内蒙古阿尔巴斯白绒山羊胚胎期皮肤毛囊中的表达,在体外合成用地高辛标记的阿尔巴斯白绒山羊KAP6基因家族成员的cRNA探针,通过原位杂交法在山羊皮肤组织切片上进行定位,检测KAP6 mRNA在绒山羊胚胎期皮肤组织中的表达情况.结果发现,KAP6mRNA在初级毛囊和次级毛囊的皮质层有强烈的表达信号,表明KAP6是绒山羊毛和绒皮质蛋白的组成成分,是皮质层中起角质化作用的重要蛋白质,直接参与了绒毛和粗毛的合成,对毛发的理化性质有重要作用.  相似文献   
493.
Blood and ovarian samples were collected at intervals of 4h prior to spawning time from medaka (Oryzias latipes) that were maturationally synchronized with artificial photoperiod (14h light: 10h dark). Plasma estradiol-17β (E2) levels increased rapidly from 16h before spawning and peaked at 8h before spawning. Follicle-enclosed oocytes (ovarian follicles) at different stages of development were isolated from the ovaries and used to study the in vitro effects of thyroid hormone (triiodothyronine; T3) on pregnant mare serum gonadotropin (GTH)-induced E2 production. GTH at a concentration of 100 IU/ml stimulated E2 production by ovarian follicles collected between 32 and 16h before spawning. At 32h before spawning, T3 (5 ng/ml) administered along with GTH (100 IU/ml) resulted in a 3.5 fold increase in E2 production, compared with GTH administered alone. These results suggest that T3 can act on ovarian follicles directly to modulate GTH-stimulated E2 production in the medaka.  相似文献   
494.
用含Fe^3+0.00、1.34×10^-3、1.34×10^-2mol/L的溶液处理卵泡细胞及垂体细胞的培养液,观察不同Fe^3+水平对离体卵泡细胞分泌雌二醇和孕酮的影响。结果表明,不同水平的Fe^3+显著抑制了离体卵泡细胞分泌雌二醇和孕酮(P〈0.05)。  相似文献   
495.
猪小腔卵泡卵母细胞体外成熟研究   总被引:27,自引:0,他引:27  
本实验通过与2~6mm猪卵泡卵母细胞相对比,研究了猪2mm以下卵泡卵母细胞的体外成熟。结果如下(1)由2mm以下卵泡获得的小(直径100.29±7.9μm)、中(109.36±3.71μm)和大(118.90±2.46μm)3类卵母细胞培养48h的成熟率分别为0、22.31%和45.45%。(2)2mm以下卵泡卵母细胞的成熟率(52.63%)显著低于2~6mm卵泡卵母细胞的成熟率(80.39%)。(3)以含PFF的培养液培养2mm以下卵泡卵母细胞其成熟率(53.54%)显著高于不含PFF的对照组(22.77%)。(4)在培养的前24h加入PMSG、后24h去除PMSG,其成熟率(41.86%)与含PMSG的培养液连续培养48h的成熟率(50.0%)无显著差异,而显著高于前24h不加PMSG,后24h加入PMSG培养的成熟率(5.41%);也显著高于以下不含PMSG的培养液连续培养48h的成熟率(3.3%)。  相似文献   
496.
用常规石蜡切片法研究水牛卵泡在卵巢中的分布规律与结构特征。结果表明各级卵泡的分布具有明显的区域性;原始卵泡位于卵巢皮质的最外层,形成原始卵泡层,初级卵泡位于皮质的中层,次级卵泡位于富含血管的皮质最内层;原始卵泡、初级卵泡和次级卵泡的直径分别为(36.9±7.7)μm、(48.7±8.9)μm和(91.9±27.3)μm,与之对应卵母细胞的直径分别为(19.6±6.0)μm、(27.3±7.1)μm和(49.1±17.4)μm;原始卵泡和初级卵泡的颗粒细胞数为(10.8±2.3)个和(18.1±3.1)个;次级卵泡含有2~6层颗粒细胞,2~4层的颗粒细胞分布不均。  相似文献   
497.
With the completion of the draft assembly of the giant panda genome sequence, RNA sequencing technology has been widely used in genetic research on giant pandas. We used RNA-seq to examine black and white hair follicle samples from adult pandas. By comparison with the giant panda genome, 75 963 SNP loci were labeled, 2426 differentially expressed genes (DEGs) were identified, and 2029 new genes were discovered, among which 631 were functionally annotated. A cluster analysis of the DEGs showed that they were mainly related to the Wnt signaling pathway, ECM–receptor interaction, the p53 signaling pathway, and ribosome processing. The enrichment results showed that there were significant differences in the regulatory networks of hair follicles with different colors during the transitional stage of hair follicle resting growth, which may play a regulatory role in melanin synthesis during growth. In conclusion, our results provide new insights and more data support for research on the color formation in giant pandas.  相似文献   
498.
The aims of this study were to analyse the protein phosphatase 1 regulatory subunit 11 (PPP1R11) expression and cellular localization in yak follicles and investigate its effects on cell proliferation, apoptosis and oestrogen secretion in granulosa cells (GCs). Ten healthy and non-pregnant female yaks (4-year-old) were used as experimental animals. The mRNA relative expression level of PPP1R11 in GCs from small (<3.0 mm), medium (3.0–5.9 mm) and large (6.0–9.0 mm) follicles was detected by RT-qPCR, and the cellular localization of PPP1R11 protein was detected by immunohistochemistry staining (IHC). After isolation, culture and identification of yak GCs in vitro, si-PPP1R11 and si-NC (negative control) were transfected into GCs. RT-qPCR and immunofluorescence staining were used to evaluate the interference efficiency, and ELISA was performed to detect oestrogen concentration. Then, EdU staining and TUNEL staining were conducted to analyse cell proliferation and apoptosis. In addition, the oestrogen synthesis, proliferation- and apoptosis-related genes were detected by RT-qPCR after knockdown PPP1R11. The results showed that PPP1R11 is mainly located in ovarian GCs, and the expression levels of PPP1R11 in GCs from large follicles were significantly higher than that from medium and small follicles. Transfection of si-PPP1R11 into GCs could significantly inhibit the expression of PPP1R11. Interestingly, the oestrogen secretion ability and the expression level of oestrogen pathway-related genes (STAR, CYP11A1, CYP19A1 and HSD17B1) were also significantly downregulated. Moreover, the proportion of positive cells was decreased, and cellular proliferation-related genes (PCNA, CCNB1 and CDC25A) were significantly downregulated after knockdown PPP1R11. However, the proportion of apoptotic cells was increased, and apoptosis-related genes (BAX, CASP3 and P53) were significantly upregulated. Taken together, this study was the first revealed the expression and cellular localization of PPP1R11 in yak follicles. Interference PPP1R11 could reduce oestrogen secretion, inhibit proliferation and promote apoptosis in GCs, which provided a basis for further studies on the regulatory mechanism of PPP1R11 in follicle development.  相似文献   
499.
旨在探究KRT16在长毛兔毛囊发育过程中的表达规律及功能。本试验选取12只健康的6月龄皖系长毛兔,于剪毛后在生长期、退行期和休止期选取背部皮肤采样。通过克隆得到兔KRT16基因的编码序列,利用生物信息学软件对KRT16编码序列(CDS)的生物学特性进行初步分析。实时荧光定量PCR(quantitative real-time PCR,qRT-PCR)分析KRT16在毛囊不同时期表达量。在毛囊毛乳头细胞(dermal papilla cell, DPC)中过表达和敲低KRT16,探究KRT16对毛囊生长发育相关基因的调控作用,以及对DPC增殖的影响。结果显示,KRT16基因的编码序列全长1 431 bp,可编码476个氨基酸,在不同哺乳动物中表现出高度同源性。实时荧光定量PCR结果显示,在毛囊发育周期中,KRT16在毛囊发育周期呈现出不同的表达水平,在生长期高表达。通过在兔毛乳头细胞中过表达与敲减KRT16,检测毛囊发育相关基因的表达水平变化,过表达KRT16后,SFRP2和TGFβ1基因的mRNA表达量极显著下降(P<0.01),BCL2、CCND1、EGF、LEF1和CTNNB...  相似文献   
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