孤儿受体TR3与人CNTF受体基因中顺式元件作用机制的研究

应用两对人工合成的寡核苷酸引物,分别通过ＰＣＲ扩增,得到了ＣＮＴＦＲα－Ｉ５ＮＢＲＥ序列两侧的两个扩增片段,将其和在ＥｃｏＲⅤ位点切开的ｐＴ７ｂｌｕｅ一起定向连接,得到了插入在ｐＴ７ｂｌｕｅ的ＥｃｏＲⅤ位点的缺失了ＮＢＲＥ序列的ＣＮＴＦＲα－Ｉ５,然后再将其切下,插入到具有ＳＶ４０起动子的ＣＡＴ基因表达载体的ＢｇｌⅡ位点,构建了ＣＡＴ报道基因．细胞转染和ＣＡＴ实验表明,缺失ＮＢＲＥ后,ＣＮＴＦＲα－Ｉ５仍具有增强子功能,ＴＲ３通过该增强子对ＣＮＴＦＲα的表达具有诱导作用,说明这种诱导作用并不是单一通过ＮＢＲＥ序列进行的．     

核孤儿受体TR3/nur77与一种新细胞凋亡机制

核孤儿受体TR3/nur77是一种立刻早期基因（immediate-early gene）的产物,与固醇类激素受体结构相似,是核受体超家族的重要成员之一,可被多种生长因子或凋亡诱导剂诱导表达,具有复杂的生物学功能,涉及细胞增殖、分化发育和凋亡过程.最近对其诱导凋亡机制的研究取得了重大进展,发现当细胞受到凋亡诱导剂刺激后,TR3基因表达升高,其产物从细胞核移位至线粒体膜,引起细胞色素c释放,从而导致细胞凋亡.即TR3的转录激活功能和诱导凋亡功能是由其不同的亚细胞定位结合所决定的,其诱导凋亡过程与其对基因的反式激活功能无关.核转录因子p53也具有类似情况.这种核转录因子由细胞核移位至细胞浆并发挥生物学功能的调控方式是一种新模式,可能具有重要的生物学意义.     

雌激素受体在小鼠睾丸表达的免疫组织化学研究

观察雌激素受体在小鼠睾丸的定位与分布。取Ａ／Ｊ系小鼠睾丸, 制备石蜡切片。用间接酶标免疫组织化学和高温处理抗原暴露技术显示雌激素受体的所在部位。睾丸所有Ｌｅｙｄｉｇ 细胞和约２０％ 的肌样细胞的胞核呈雌激素受体阳性反应。睾丸支持细胞和生精细胞为阴性。本研究首次用免疫组织化学技术证明了睾丸中雌激素受体的存在,并定位于Ｌｅｙｄｉｇ 细胞和部分肌样细胞的胞核。为研究雌激素对雄性生殖功能的调节提供了形态学依据。     

诱导受体3（DcR3）在胆管癌中的表达及意义

目的:观察胆管癌组织及血清中诱导受体3(decoy receptor 3,DcR3)蛋白的表达及其临床价值。方法:采用免疫组化S-P法检测45例胆管癌、15例癌旁胆管正常组织中DcR3蛋白的表达,ELISA法检测31例胆管癌及18例胆道良性疾病患者和28例正常人外周血清中DcR3的水平。结果:45例胆管癌组织中DcR3阳性表达29例,阳性率为64.4%,胆管正常组织中无阳性表达。DcR3的表达与肿瘤临床分期、肿瘤浸润和转移有关(P<0.05)。胆管癌患者及胆管良性疾病患者血清DcR3水平分别为152.2535.94 pg/ml,98.35 14.27 pg/ml,均高于正常人。胆管癌患者与胆道良性疾病患者血清DcR3水平相比差异有显著性(P<0.01)。结论:DcR3在胆管癌组织中表达增高。DcR3的表达与胆管癌的发生、发展以及转移有关,可成为治疗胆管癌的一个新靶点。血清DcR3的检测对胆管癌的诊断有一定的临床价值。     

诱导受体3（DcR3）在胆管癌中的表达及意义

目的：观察胆管癌组织及血清中诱导受体3（decoy receptor 3,DcR3）蛋白的表达及其临床价值。方法：采用免疫组化S-P法检测45例胆管癌、15例癌旁胆管正常组织中DcR3蛋白的表达,ELISA法检测31例胆管癌及18例胆道良性疾病患者和28例正常人外周血清中DcR3的水平。结果：45例胆管癌组织中DcR3阳性表达29例,阳性率为64.4%,胆管正常组织中无阳性表达。DcR3的表达与肿瘤临床分期、肿瘤浸润和转移有关（P〈0.05）。胆管癌患者及胆管良性疾病患者血清DcR3水平分别为152.2535.94 pg/ml,98.35 14.27 pg/ml,均高于正常人。胆管癌患者与胆道良性疾病患者血清DcR3水平相比差异有显著性（P〈0.01）。结论：DcR3在胆管癌组织中表达增高。DcR3的表达与胆管癌的发生、发展以及转移有关,可成为治疗胆管癌的一个新靶点。血清DcR3的检测对胆管癌的诊断有一定的临床价值。     

EDN3在不同毛色小鼠皮肤中的表达与定位

内皮素3（endothelin 3, EDN3）对早期黑色素细胞的迁移及增殖分化有促进作用,并可通过与其受体结合促进黑色素的合成。EDN3在不同毛色小鼠皮肤中的差异及其在毛色形成过程中的作用仍有待研究。实时荧光定量PCR结果显示,灰色小鼠皮肤中EDN3的表达量显著高于黑色及棕色小鼠,约为其2倍(P<0.01)。蛋白免疫印迹结果显示,灰色小鼠皮肤内EDN3的含量为黑色小鼠的5倍,棕色小鼠为黑色小鼠的2倍。ELISA结果表明,灰色小鼠皮肤中EDN3的蛋白质表达量分别是黑色和棕色小鼠的1.8倍和1.4倍(P<0.01)。免疫组织化学显示,EDN3在毛囊的毛基质及内外毛根鞘有明显表达,毛乳头等部位有少量表达。EDN3在不同毛色小鼠皮肤中的表达存在显著差异,是维持黑色素细胞存在不可缺少的因子,可能对两种色素颗粒的相互转化有一定的作用。     

P2X3受体在感觉神经节的表达

用免疫组织化学与原位杂交研究P2X3受体在背根神经节,三叉神经节和结状神经节的分布。结果显示：1、原位杂交;在三种感觉神经节中,95%左右的神经节细胞为P2X3mRNA阳性,中、小型神经节细胞的杂交信号一般要比大型的神经节细胞强一些,2、免疫组织化学;免疫组织化学结果与原位杂交结果基本一致。此外,在各神经节内,均显示出许多P2X3免疫阳性神经纤维,在足掌表皮也显示许多P2X3免疫反应阳性纤维,结果提示：P2X3不仅参与机体的痛觉的形成,还可能参与其它感觉,如本体感觉等的形成。     

着床期小鼠子宫内膜中EGF及其受体转录和表达状况的研究

为探讨表皮生长因子（epidermal growth factor,EGF)在胚泡着床过程中的作用。本文应用原位杂交和免疫组织化学方法,检测了EGE及其受体在胚泡着床前后小鼠子宫内膜中的转录和表达。结果显示：未孕和受精后第4-5天,子宫内膜表面上皮和腺上皮细胞仍呈EGF,EGFR原位杂交和免疫组化阴性着色,受精后第4-5天子宫内膜基质细胞EGF及其受体转录和表达较未孕期增强,受精后第6天,EGF及其受体免疫组化和原位杂交阳性着色主要分布于初级蜕膜带（primary decidual zone,PDZ);随着胚泡植入的进行,PDZ区蜕膜细胞EGF及其受体的转录和表达明显减少,而PDZ周围蜕膜细胞EGF及其受体的转录和表达增强,结果提示,EGF是小鼠胚泡着床过程中的一个重要调节因子。     

神经激肽B受体在小鼠消化道内的定位

采用免疫组织化学ABC染色方法研究了神经激肽B受体（NK3r)在小鼠消化道的分布。MK3r样阳性的神经无胞体及神经纤维主要分布在十二指肠,空肠,回肠及结肠的粘膜下层神经丛和肌间神经丛,NK3r样阳性产物在食管,胃和直肠的神经丛中未见分布;NK3r样阳性产物大部分避限于神经细胞表面,也存在于胞和一些轴突内部,并在胞质中较细胞表面染色浅。。统计结果表明NK3r样免疫阳性神经元占肠神经系统神经元总数的0．5－1％,提示小鼠消化道内NK3r样阳性神经元可能参与消化功能的调节。     

P2X_3受体在感觉神经节的表达

用免疫组织化学与原位杂交研究 P2 X3受体在背根神经节、三叉神经节和结状神经节的分布。结果显示 :1.原位杂交 :在三种感觉神经节中 ,95 %左右的神经节细胞为 P2 X3m RNA阳性 ,中、小型神经节细胞的杂交信号一般要比大型的神经节细胞强一些。 2 .免疫组织化学 :免疫组织化学结果与原位杂交结果基本一致。此外 ,在各神经节内 ,均显示出许多P2 X3免疫阳性神经纤维 ,在足掌表皮也显示许多 P2 X3免疫反应阳性纤维。结果提示 :P2 X3不仅参与机体的痛觉的形成 ,还可能参与其它感觉 ,如本体感觉等的形成     

Stage dependent and androgen inductive expression of orphan receptor TR4 in rat testis

In this study, we investigated the expression of TR4 in different stages of seminiferous tubules and the relationship between TR4 and androgen in rat testis. We found that TR4 was stage-dependently expressed in rat seminiferous tubules, T withdrawal induced by high doses of testosterone undecanoate and ethane dimethane sulfonate inhibit TR4 expression in rat testis, and testosterone induced TR4 expression in co-cultured primary germ/Sertoli cells. Furthermore, we demonstrated that androgen receptor could enhance TR4-mediated transactivation activity in testis cells in the presence of testosterone. Together, these data indicate that the expression of TR4 in rat testis is stage dependent and androgen inductive, and suggest the important role of orphan receptor TR4 in spermatogenesis.     

Identification of the histamine H1 receptor gene as a differentially repressed target of the human TR2 orphan receptor

We have identified a DNA response element (TR2RE-HR) in the 3 flanking region of the human histamine H1 receptor gene as a target for the TR2 orphan receptor, a member of the steroid/thyroid hormone receptor superfamily. The application of both tetracycline inducible and improved differential display systems has allowed us to isolate a cDNA fragment differentially regulated by the expression of the TR2 orphan receptor. Northern blot and sequencing analysis demonstrated that the expression of the human histamine H1 receptor gene was differentially repressed by the TR2 orphan receptor. Electrophoretic mobility shift assay further revealed a specific binding (dissociation constant = 26.2 nM) between the TR2 orphan receptor and the wildtype TR2RE-HR, but not the mutant TR2RE-HR. In addition, reporter gene expression assay indicated that the TR2 orphan receptor may suppress the expression of luciferase activities in a dose-dependent manner via the TR2RE-HR in HeLa cells. Our results demonstrate that the histamine H1 receptor gene could represent one of the target genes directly regulated by the human TR2 orphan receptor.     

Post-meiotic expression of the mouse dihydropyrimidinase-related protein 3 (DRP-3) gene during spermiogenesis

The dihydropyrimidinase-related protein (DRP) family, originally identified in humans by their homology to dihydropyrimidinase, contains at least four members. Genes of this family, and their counterparts in other mammals and chickens, are expressed mainly in fetal and neonatal brain, suggesting that the encoded proteins have a physiological role in the development of the central nervous system. In addition, the DRP-3 gene is expressed in testis as a shorter mRNA than the brain form. As a first step in understanding the extra-neuronal function of DRP-3, the structure and expression of testis DRP-3 were examined. Testis DRP-3 cDNA showed the same sequence as brain DRP-3 cDNA, except for the 5′-terminal end, which encodes a 5′-untranslated region and the 11 N-terminal amino acid residues, indicating that the two forms of DRP-3 mRNA were transcribed from a single copy gene. Northern blotting analysis detected DRP-3 mRNA in 30-, 40- and 70-day-old, but not in 10- and 20-day-old testes. In situ hybridization analysis indicated that the expression of DRP-3 in testis is restricted to post-meiotic round spermatids. This is the first report of the expression of DRP genes in extra-neuronal cells. Mol. Reprod. Dev. 51:105–111, 1998. © 1998 Wiley-Liss, Inc.     

Cloning and characterization of a family C orphan G-protein coupled receptor

Members of the family C receptors within the G-protein coupled receptor superfamily include the metabotropic glutamate receptors, GABA(B) receptors, the calcium-sensing receptor (CaSR), the V2R pheromone receptors, the T1R taste receptors, and a small group of uncharacterized orphan receptors. We have cloned and studied the mouse GPRC6A family C orphan receptor. The open reading frame codes for a protein with highest sequence identity to the fish 5.24 odorant receptor and the mammalian CaSR. The gene structure shows a striking resemblance to that of the CaSR. Results from RT-PCR analyses showed that mouse GPRC6A mRNA is expressed in mouse brain, skeletal muscle, heart, lung, spleen, kidney, liver, and in the early stage mouse embryo. Immunocytochemical analysis of the cloned mouse GPRC6A cDNA expressed in human embryonic kidney 293 cells demonstrated that GPRC6A was present on the plasma membrane, as well as in the endoplasmic reticulum and nuclear envelope membranes of transfected cells. A chimeric cDNA construct in which the extracellular ligand binding domain of the fish 5.24 amino acid-activated odorant receptor was ligated to the complementary downstream sequence of the mouse GPRC6A receptor indicated that GPRC6A is coupled to phosphoinositol turnover and release of intracellular calcium. Further studies with mouse GPRC6A expressed in Xenopus laevis oocytes demonstrated that this receptor possesses a pharmacological profile resembling that of the fish 5.24 odorant receptor. These findings suggest that GPRC6A may function as the receptor component of a novel cellular transmitter system in mammals.     

Estrogen receptor protein and mRNA expression in the ovary of sheep

Using immunohistochemistry and in situ hybridization, we attempted to identify the estrogen receptor (ER) protein and messenger RNA (mRNA) in sheep ovaries during the follicular phase of the estrous cycle. Monoclonal anti-ER antibodies H222 and 1D5 were used for localizing estrogen receptor on ovarian cryo-sections. Labeling for ER was found over the nuclei of surface epithelium, interstitial tissue, and granulosa cells of small as well as large ovarian follicles. In the preantral and small antral follicles, intense nuclear ER labeling was observed in mural granulosa cells and particularly in cumulus/granulosa cells surrounding the oocyte. In the large healthy looking follicles, greater diversity in labeling for ER was observed, which is characterized by mixed populations of granulosa cells expressing positive and more or less negative nuclear labeling. Such a pattern of labeling was particularly evident in follicles showing the signs of atresia. Generally, more intense nuclear staining was localized in granulosa cells proximal to basal membrane. In situ hybridization studies revealed the presence of ER mRNA in ovarian tissue. Autoradiographic visualization localized ER mRNA expression over the granulosa cells of healthy follicles of all sizes. Level of hybridization signal was comparable in mural and cumulus granulosa cells. In atretic follicles, the level of hybridization signal in granulosa cells was comparable to that of healthy follicles. A relatively weaker level of labeling was observed in granulosa cells dispersed in follicular antrum in follicles with advanced atretic lesions. Theca cells expressed a lower level of labeling than granulosa cells. Specificity of labeling for both ER protein and mRNA in ovary was proved by parallel probing the ovine uterus. Ovine ER recognition by both H222 and 1D5 antibodies was also proved by immunoblotting. These studies demonstrate the presence of the estrogen receptor and its messenger RNA in the sheep ovary and suggest an autocrine/paracrine role of estradiol and its receptor in the regulation of ovarian follicle development in sheep. Mol. Reprod. Dev. 48:53–62, 1997. © 1997 Wiley-Liss, Inc.