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1.
Cloning of a serotonin transporter affected by antidepressants   总被引:35,自引:0,他引:35  
A complementary DNA clone for a serotonin (5HT) transporter has been isolated from rat basophilic leukemia cells. The complementary DNA sequence predicts a 653-amino acid protein with 12 to 13 putative transmembrane domains. The 5HT transporter has significant homology to the gamma-aminobutyric acid, dopamine, and norepinephrine transporters. Uptake by CV-1 cells expressing the transporter complementary DNA resembles 5HT uptake by platelets and brain synaptosomes; it is sensitive to antidepressants, amphetamine derivatives, and cocaine.  相似文献   

2.
Sequence and expression of human estrogen receptor complementary DNA   总被引:95,自引:0,他引:95  
The mechanism by which the estrogen receptor and other steroid hormone receptors regulate gene expression in eukaryotic cells is not well understood. In this study, a complementary DNA clone containing the entire translated portion of the messenger RNA for the estrogen receptor from MCF-7 human breast cancer cells was sequenced and then expressed in Chinese hamster ovary (CHO-K1) cells to give a functional protein. An open reading frame of 1785 nucleotides in the complementary DNA corresponded to a polypeptide of 595 amino acids and a molecular weight of 66,200, which is in good agreement with published molecular weight values of 65,000 to 70,000 for the estrogen receptor. Homogenates of transformed Chinese hamster ovary cells containing a protein that bound [3H]estradiol and sedimented as a 4S complex in salt-containing sucrose gradients and as an 8 to 9S complex in the absence of salt. Interaction of this receptor-[3H]estradiol complex with a monoclonal antibody that is specific for primate ER confirms the identity of the expressed complementary DNA as human estrogen receptor. Amino acid sequence comparisons revealed significant regional homology among the human estrogen receptor, the human glucocorticoid receptor, and the putative v-erbA oncogene product. This suggests that steroid receptor genes and the avian erythroblastosis viral oncogene are derived from a common primordial gene. The homologous region, which is rich in cysteine, lysine, and arginine, may represent the DNA-binding domain of these proteins.  相似文献   

3.
Cloning and expression of a rat brain GABA transporter   总被引:45,自引:0,他引:45  
A complementary DNA clone (designated GAT-1) encoding a transporter for the neurotransmitter gamma-aminobutyric acid (GABA) has been isolated from rat brain, and its functional properties have been examined in Xenopus oocytes. Oocytes injected with GAT-1 synthetic messenger RNA accumulated [3H]GABA to levels above control values. The transporter encoded by GAT-1 has a high affinity for GABA, is sodium-and chloride-dependent, and is pharmacologically similar to neuronal GABA transporters. The GAT-1 protein shares antigenic determinants with a native rat brain GABA transporter. The nucleotide sequence of GAT-1 predicts a protein of 599 amino acids with a molecular weight of 67 kilodaltons. Hydropathy analysis of the deduced protein suggests multiple transmembrane regions, a feature shared by several cloned transporters; however, database searches indicate that GAT-1 is not homologous to any previously identified proteins. Therefore, GAT-1 appears to be a member of a previously uncharacterized family of transport molecules.  相似文献   

4.
We describe synthetic membranes in which the molecular recognition chemistry used to accomplish selective permeation is DNA hybridization. These membranes contain template-synthesized gold nanotubes with inside diameters of 12 nanometers, and a "transporter" DNA-hairpin molecule is attached to the inside walls of these nanotubes. These DNA-functionalized nanotube membranes selectively recognize and transport the DNA strand that is complementary to the transporter strand, relative to DNA strands that are not complementary to the transporter. Under optimal conditions, single-base mismatch transport selectivity can be obtained.  相似文献   

5.
The binding of [3H]diazepam to benzodiazepine receptors was studied in extensively washed membranes of rat cerebral cortex in the presence of the depressant barbiturate, pentobarbital. Pentobarbital, like the endogenous neurotransmitter gamma-aminobutyric acid (GABA), increased the basal binding and also potentiated the GABA-enhanced binding of [3H]diazepam to benzodiazepine receptors by increasing the apparent affinity of [3H]diazepam for the benzodiazepine receptor. The concentrations of pentobarbital necessary to elicit these effects in vitro are the same as those observed after treatment with pharmacologically relevant doses, suggesting that a common neurochemical association may exist between these types of compounds.  相似文献   

6.
[目的]将链替代扩增技术与核酸修饰纳米金积聚变色的光学特性相结合,设计了一种新型的直观检测3′端暴露单链核酸的方法,实现对单链核酸的高灵敏度检测。[方法]设计一条含有硫代修饰酶切位点的单链核酸(ZDNA),其酶切位点5′端是能将核酸修饰纳米金变色的Linker序列,3′端是能与Target单链核酸3′端完全互补的H序列。当无Target存在时,Linker会充分暴露,能使核酸修饰纳米金积聚呈现紫色;但是当Target存在时,会与H序列完全互补,作为ZDNA的引物进入链替代扩增循环,形成的新链不断与Linker序列互补,不能使核酸修饰纳米金积聚呈现红色,从而间接检测了Target单链核酸。[结果]通过一系列试验确定检测体系,具体为:40μl修饰纳米金溶液(0.52 nmol/L)加入10μl酶循环体系(ZDNA20 nmol/L,33 mmol/L Tris-HCl(pH值7.9);10 mmol/L MgCl2;66 mmol/LNaCl;0.5 mmol/LdNTP;0.1 mg/ml BSA;0.05 U/μl klenow;1 U/μl Hinc II),直观或紫外检测并绘制Target浓度与纳米金积聚程度的标准曲线,表明Target浓度在1~200 pmol/L的范围内呈现良好的线性关系,R2=0.946,最低检测限是1 pmol/L。[结论]链替代扩增-纳米金比色检测单链核酸方法简便、直观、成本低,与传统修饰纳米金比色检测DNA方法相比,灵敏度提高了104倍。  相似文献   

7.
[目的]为豆豉纤溶酶的进一步研究与应用奠定基础。[方法]以从芽孢杆菌中提取的总DNA为模板,根据GenBank的豆豉纤溶酶基因(AY720895.2)DNA序列设计1对引物,克隆豆豉纤溶酶基因并进行序列测定。构建毕赤酵母表达载体pL3,在毕赤酵母中表达豆豉纤溶酶基因。[结果]经PCR扩增可获得约1.1 kb的DNA片段。序列分析表明所克隆DNA片段包含1个1089 bp的开放阅读框,编码363个氨基酸。该克隆基因与所发表的豆豉纤溶酶基因序列的核苷酸序列同源性为98%,而氨基酸序列同源性达100%。[结论]所克隆的豆豉溶纤酶基因在毕赤酵母中成功表达,且表达产物具有正常的生物学活性。  相似文献   

8.
A complementary DNA (cDNA) clone that encodes inositol 1,4,5-trisphosphate 3-kinase was isolated from a rat brain cDNA expression library with the use of monoclonal antibodies. This clone had an open reading frame that would direct the synthesis of a protein consisting of 449 amino acids and with a molecular mass of 49,853 daltons. The putative protein revealed a potential calmodulin-binding site and six regions with amino acid compositions (PEST regions) common to proteins that are susceptible to calpain. Expression of the cDNA in COS cells resulted in an approximately 150-fold increase in inositol 1,4,5-trisphosphate 3-kinase activity of these cells.  相似文献   

9.
Cloning and expression of a cocaine-sensitive rat dopamine transporter   总被引:33,自引:0,他引:33  
The action of dopamine and other monoamine neurotransmitters at synapses is terminated predominantly by high-affinity reuptake into presynaptic terminals by specific sodium-dependent neurotransmitter transport proteins. A complementary DNA encoding a rat dopamine transporter has been isolated that exhibits high sequence similarity with the previously cloned norepinephrine and gamma-aminobutyric acid transporters. Transient expression of the complementary DNA in HeLa cells confirms the cocaine sensitivity of this transporter.  相似文献   

10.
牛世全  胡娇龙  达文燕 《安徽农业科学》2013,(23):9569-9570,9574
[目的]比较制备放线菌基因组DNA PCR模板的两种方法液氮研磨法及TE煮沸法.[方法]以从河西走廊盐碱土壤中分离鉴定的8属16株菌为材料,包括糖丝菌属(Saccharothrix)Ⅳ23-3-4、类诺卡氏菌属(Nocardioides)Ⅴ22-5-1、原小单孢菌属(Promicromonospora)ⅨX5-4-3、小单孢菌属(Micromonospora)Ⅱ23-4-1、放线多孢菌属(Actinopolyspora)Ⅳ8-2-5、拟诺卡氏菌属(Nocardiopsis)Ⅱ8-4-3、链单孢菌属(Streptomonospora)DA01305、链霉菌属金色类群DA03401、链霉菌属金色类群DA01408、链霉菌属蓝色类群DA09140、链霉菌属金色类群DA01308、链霉菌属灰红紫类群DA05213、链霉菌属蓝色类群DA11417、链霉菌属粉红孢类群DA04401、链霉菌属灰红紫类群DA04402、链霉菌属球孢类群DA04307.对两种方法制备的PCR模板进行16S rDNA的扩增,PCR产物进行电泳检测.[结果]两种方法均能得到比较清晰的目的条带,但TE煮沸法简化了放线菌基因组DNA PCR模板制备的过程,可用于高通量放线菌PCR模板的快速制备.[结论]该研究为大批量菌株的快速鉴别和系统分类提供了有效的方法.  相似文献   

11.
Primary structure and biochemical properties of an M2 muscarinic receptor   总被引:33,自引:0,他引:33  
A partial amino acid sequence obtained for porcine atrial muscarinic acetylcholine receptor was used to isolate complementary DNA clones containing the complete receptor coding region. The deduced 466-amino acid polypeptide exhibits extensive structural and sequence homology with other receptors coupled to guanine nucleotide binding (G) proteins (for example, the beta-adrenergic receptor and rhodopsins); this similarity predicts a structure of seven membrane-spanning regions distinguished by the disposition of a large cytoplasmic domain. Stable transfection of the Chinese hamster ovary cell line with the atrial receptor complementary DNA leads to the binding of muscarinic antagonists in these cells with affinities characteristic of the M2 receptor subtype. The atrial muscarinic receptor is encoded by a unique gene consisting of a single coding exon and multiple, alternatively spliced 5' noncoding regions. The atrial receptor is distinct from the cerebral muscarinic receptor gene product, sharing only 38% overall amino acid homology and possessing a completely nonhomologous large cytoplasmic domain, suggesting a role for the latter region in differential effector coupling.  相似文献   

12.
[目的]克隆花特异表达启动子PchsA,将此启动子与蓝色基因“F3′5′H”构建新的表达载体,拟以该启动子驱动“F3′5′H”在其他花色中特异表达。[方法]根据GenBank报道的矮牵牛启动子的序列设计并合成一对特异引物,以蓝紫色矮牵牛总DNA为模板,用PCR仪扩增目的片段。[结果]PCR扩增出的启动子DNA片段长约550bp,回收后连接到PGM-T质粒载体上,经转化、筛选确定重组子,酶切鉴定后送上海生工生物工程公司测序,得到片段长度为553bp。经DNAMAN软件分析和GenBank上BLAST序列比对,显示序列与已报道序列同源性为98.55%。应用pcgene软件进行序列分析,结果表明试验克隆的启动子含有启动子所必须的所有调控元件,这与报道的序列基本一致。[结论]试验成功地克隆了CHSA启动子并将其与“F3′5′H”构建成能够在植物中进行道传转化的表达载体,为培育新型花色新品种奠定了基础。  相似文献   

13.
A corticosteroid receptor in neuronal membranes   总被引:22,自引:0,他引:22  
Steroids may rapidly alter neuronal function and behavior through poorly characterized, direct actions on neuronal membranes. The membrane-bound receptors mediating these behavioral responses have not been identified. [3H]Corticosterone labels a population of specific, high-affinity recognition sites (dissociation constant = 0.51 nanomolar) in synaptic membranes from an amphibian brain. These binding sites were localized by receptor autoradiography in the neuropil, outside the regions of perikarya. The affinities of corticoids for this [3H]corticosterone binding site were linearly related to their potencies in rapidly suppressing male reproductive behavior. Thus, it appears that brain membranes contain a corticosteroid receptor that could participate in the regulation of behavior.  相似文献   

14.
Vitamin D3 receptors are intracellular proteins that mediate the nuclear action of the active metabolite 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]. Two receptor-specific monoclonal antibodies were used to recover the complementary DNA (cDNA) of this regulatory protein from a chicken intestinal lambda gt11 cDNA expression library. The amino acid sequences that were deduced from this cDNA revealed a highly conserved cysteine-rich region that displayed homology with a domain characteristic of other steroid receptors and with the gag-erbA oncogene product of avian erythroblastosis virus. RNA selected via hybridization with this DNA sequence directed the cell-free synthesis of immunoprecipitable vitamin D3 receptor. Northern blot analysis of polyadenylated RNA with these cDNA probes revealed two vitamin D receptor messenger RNAs (mRNAs) of 2.6 and 3.2 kilobases in receptor-containing chicken tissues and a major cross-hybridizing receptor mRNA species of 4.2 kilobases in mouse 3T6 fibroblasts. The 4.2-kilobase species was substantially increased by prior exposure of 3T6 cells to 1,25(OH)2D3. This cDNA represents perhaps the rarest mRNA cloned to date in eukaryotes, as well as the first receptor sequence described for an authentic vitamin.  相似文献   

15.
16.
李睿  沈汪洋  翟平平  陈道玉 《安徽农业科学》2011,39(4):1891-1892,1894
[目的]指导白酒生产,提高白酒质量。[方法]采用平板分离法从观音土曲中分离到7株乳酸菌(B1~B7),测定其发酵产乳酸的量。选取乳酸产量最高的1株菌B7,提取其DNA并进行16S rDNA的PCR扩增、克隆、测序。从GenBank中选取与B7同源性最高的典型菌株,下载其16S rDNA序列,采用邻位相连法构建进化树。[结果]B1~B7的产乳酸量分别为:24.7、20.7、30.7、15.2、9.5、21.8、35.7mg/100m l;对B7的基因组DNA进行16S rDNA的PCR扩增,并对纯化后的扩增产物进行TA克隆,阳性克隆经琼脂糖凝胶电泳后在3000和1 600 bp处出现电泳条带,说明B7的16S rDNA PCR扩增产物已克隆到测序载体上。同源性分析结果表明,B7为乳杆菌属的短乳杆菌。[结论]该研究从观音土曲中分离到1株高产乳酸菌——短乳杆菌。  相似文献   

17.
金华  安晓雯  姜国斌 《安徽农业科学》2009,37(31):15172-15174
[目的]克隆自然生长于黑龙江省盐碱地的羊草ClassⅡ几丁质酶基因并进行序列分析,为进一步研究几丁质酶基因的生物功能和应用奠定了基础。[方法]构建羊草叶片的cDNA文库,对其进行DNA序列测定和分析,并与GenBank中收录的植物几丁质酶基因序列及编码的氨基酸序列进行同源性比较。[结果]在羊草叶片eDNA文库中克隆出1条全长eDNA片段,片段长996bp,其中,可读框768bp,编码255个氨基酸。编码产物在结构上缺乏CBD和C-端延伸区,具有ClassⅡ几丁质酶的结构特征,其氨基酸序列与黑麦和小麦ClassⅡ几丁质酶具有很高的同源性;构建的pQE—LcChi2重组载体经诱导后表达出一个约27KD的蛋白,与推测的pQE-LcChi2基因编码产物大小一致。[结论]LcHi2基因在大肠杆菌中能够表达,是一个具有表达功能的基因。  相似文献   

18.
3-氧酰基[酰基载体蛋白]还原酶(3-oxoacyl-[acyl-carrier-protein]synthase,Kas)在辣椒素生物合成途径中起着重要作用,但其全长DNA序列仍未见报道.以辣椒益都红基因组为模板,根据同源性设计特异引物PCR扩增得到辣椒Kas基因DNA序列(GenBank登录号:HQ229922)....  相似文献   

19.
[目的]为充分开发黑曲霉在轻工业中的用途。[方法]以黑曲霉中国株(3.758)基因组DNA为模板,用LATaqDNA聚合酶对葡萄糖氧化酶(GOD)基因进行PCR扩增,扩增片段纯化后与pUCm-T载体连接后,转化到大肠杆菌DH5α感受态细胞,经琼脂糖凝胶电泳法、酶切和PCR鉴定获得阳性克隆。对获得含GOD基因的克隆进行测序,分析其蛋白质氨基酸序列及限制性内切酶的图谱。[结果]经PCR扩增获得约1.8kb的片段。获得的GOD基因编码序列共1818bp,与报道的黑曲霉(ATCC9029)GOD基因序列仅有3个碱基之差。该基因序列具有多个限制性内切酶位点。黑曲霉不同菌株与中国株(3.758)GOD基因的同源性比较表明,不同黑曲霉菌株中GOD基因不同,而菌株ATCC9029与菌株NRRL-3是同一菌株。[结论]该研究获得了GOD基因的全长序列,为GOD的生物工程生产和相关植物基因工程奠定了基础。  相似文献   

20.
巴西橡胶NBS类抗病基因同源序列的克隆与分析   总被引:1,自引:0,他引:1  
[目的]探讨巴西橡胶NBS类抗病基因同源序列的克隆与序列分析。[方法]以高抗炭疽病的巴西橡胶无性系R042为材料,根据抗病基因Prf、L6、N等的P.100p和GLPL保守结构域设计简并引物,从R042扩增具有抗病基因同源序列的片段,对分离获得的抗病基因同源序列进行Blastn、氨基酸同源性分析、序列比较和系统进化分析。[结果]从巴西橡胶高抗炭疽病无性系R042基因组DNA中分离获得1个NBS类抗病基因同源序列,经Blastn比对后发现,该抗病基因同源序列与毛果杨中的一个CC—NBS—LRR抗病蛋白的mRNA的序列同源性为66%,Blastn的E值为2e-24,推测氨基酸序列与已知抗病基因的相似性在26.9%~43.2%。[结论]序列比对与系统进化分析表明,该抗病基因同源序列具有NBS类抗病基因的所有保守序列,且与Xal的亲缘关系最近。  相似文献   

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