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The sequence of 370 bases at the 5′-end of bovine thyroglobulin mRNA has been determine. A41 base untranslated segment was found preceeding the ATG initiator codon. It is followed by an open reading frame providing the first data on thyroglobulin primary structure. Analysis of the amino acid sequence demonstrated the presence of an 18 residue hydrophobic segment representing a putative signal peptide. Comparison of the amino terminal sequence of thyroglobulin with that of peptides known to contain thyroid hormones [7,8] demonstrated that the first tyrosine in native thyroglobulin is mainly found as thyroxine in the mature iodinated protein [8]. Our results clearly identify the amino-terminal region of thyroglobulin as an important hormonogenic domain of the protein.  相似文献   
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中华绒螯蟹卵巢RACE Cdna文库的构建   总被引:4,自引:0,他引:4  
应用抑制性差减杂交技术 ,已经获得了中华绒螯蟹卵巢发育过程中差异表达基因的部分cDNA序列。为了进一步获得基因的全长cDNA序列 ,运用SMART技术 ,成功构建了中华绒螯蟹卵巢 (Ⅲ期 )RACEcDNA文库。琼脂糖凝胶电泳结果表明 ,文库所含全长cDNA的长度主要集中在 5 0 0~ 2 0 0 0bp之间 ,RACEPCR结果表明 ,所用基因特异性引物与接头引物皆能扩增出产物 ,说明所构文库的质量较好 ,适于用RACE方法从中分离中华绒螯蟹卵巢发育相关基因的全长cDNA。  相似文献   
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To study the gene expression profiles between immunologically injured liver cell and normal liver cell of mice and to screen on a large scale the differentially expressed genes associated with the formation of liver injury, the experimental mice were randomly divided into the normal group for controlling and the immunologically liver-injured group induced by BCG and LPS. The liver mRNA of the two groups were extracted respectively and reversely-transcribed to cDNA with the incorporation of different fluorescence (Cy3, Cy5) labeled dUTP as the hybridization probes. The mixed probes were hybridized to the cDNA microarray chips. The fluorescent signal results were acquired by scanner ScanArray 4000 and analyzed with software GenePix Pro 3.0. Among the 14112 target genes, 293 genes were found to be significantly differentially expressed, in which 188 genes were up-regulated and 105 genes were down-regulated. Based on the analysis of biological functions of those differentially expressed genes, it was indicated that the occurrence and development of mouse liver damage induced by BCG and LPS were highly correlated with the processes of immune reactions, cell synthesis, metabolism, apoptosis and transportation in liver cell, which might be quite important for elucidating the regulatory network of gene expression associated with the liver damage, also important for finally discovering the pathogenic mechanisms of immunological liver damage.  相似文献   
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To identify salt stress-responsive genes, we constructed a cDNA library with the salttolerant rice cultivar, Lansheng. About 15000 plasmids were extracted and dotted on filters with Biomeck 2000 HDRT system or by hand. Thirty genes were identified to display altered expression levels responding to 150 mmol/L NaCl. Among them eighteen genes were up-regulated and the remainders downregulated. Twenty-seven genes have their homologous genes in GenBank Databases. The expression of twelve genes was studied by Northern analysis. Based on the functions, these genes can be classified into five categories, including photosynthesis-related gene, transportrelated gene, metabolismrelated gene, stress-or resistancerelated gene and the others with various functions. The results showed that salt stress influenced many aspects of rice growth. Some of these genes may play important roles in plant salt tolerance.  相似文献   
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利用cDNA微阵列技术快速筛选具有较强降解木质纤维素能力的白腐真菌粗毛栓菌(Trametes gallica)的表达基因.利用木质素生物降解模式菌株黄孢原毛平革菌(Phanerochaete chrysosporium)的cDNA制备研究所用微阵列.在含有2 596个cDNA片段的芯片上共检测到172个阳性克隆,其中有165个克隆的荧光信号比值(Cy-5/Cy-3)在0.5和2.0之间,占所检测阳性克隆数的95.9%.对应于在限氮条件下生长5天和12天的粗毛栓菌培养物,分别有3个和4个时序特异性差异表达基因.随机挑取122个克隆进行测序和序列比对,发现所测序列中有118个能够很好地定位于黄孢原毛平革菌的基因组上.结果显示,粗毛栓菌与黄孢原毛平革菌在表达序列上存在较大差异,表明这两种真菌之间存在着较远的亲缘关系.通过同源性比对分析,发现2个令人感兴趣的克隆,一个对应于黄孢原毛平革菌过氧化物酶基因lpoB的部分片段,另一个为编码一种热激蛋白的基因.  相似文献   
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