The gene encoding the beta-subunit of rat luteinizing hormone. Analysis of gene structure and evolution of nucleotide sequence.
The gene encoding the beta-subunit of rat luteinizing hormone. Analysis of gene structure and evolution of nucleotide sequence.
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DOI：
10.1016/s0021-9258(17)42573-7
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发表时间：
1984-12
期刊：
影响因子：
--
通讯作者：
L. Jameson;W. W. Chin-W.;Anthony N. Hollenberg;A. S. Chang;J. Habener
中科院分区：
文献类型：
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作者：
L. Jameson;W. W. Chin-W.;Anthony N. Hollenberg;A. S. Chang;J. Habener
从克隆于λ噬菌体Charon 4A中的基因组DNA片段中测定了大鼠促黄体生成素(L H)β亚基基因的核苷酸序列。大鼠基因组DNA限制性内切酶的印迹杂交表明，该基因以单拷贝形式存在。转录单位大小为0.98kb，包含三个外显子，中间分别有245和225个碱基对的两个内含子。氨基酸密码子-16/-15和+41/+42的外显子/内含子连接的位置在大鼠黄体生成素β基因和相关基因人黄体生成素β和绒毛膜促性腺激素β之间保守。通过对去卵巢大鼠脑垂体mRNA进行S1核酸酶作图和寡核苷酸启动的逆转录，确定转录起点在翻译起点的上游7个碱基对。该基因5‘侧翼区存在典型的启动子元件，包括转录起始上游167bp的Goldberg-Hogness序列、31bp的TATAAA和一致的CAAT box序列。在转录单元5‘侧翼的近200个碱基内，大鼠和人的促黄体生成素β基因有很强的同源性，这表明这些区域包括可能对基因表达调控重要的序列。大鼠黄体生成素β基因的分离和鉴定进一步明确了糖蛋白激素基因的进化，并将有助于研究调节黄体生成素基因表达的细胞和分子机制。
The nucleotide sequence of the gene encoding the beta-subunit of rat luteinizing hormone (LH beta) has been determined from a genomic DNA fragment cloned in lambda phage Charon 4A. Blot hybridization of restriction enzyme digests of rat genomic DNA indicates that the gene is present in a single copy. The transcriptional unit is 0.98 kilobase in size and contains three exons interrupted by two introns of 245 and 225 base pairs (bp). The locations of the exon/intron junctions at amino acid codons -16/-15 and +41/+42 have been conserved between the rat LH beta gene and the related genes, human LH beta and human chorionic gonadotropin beta. Using S1 nuclease mapping and oligonucleotide-primed reverse transcription of ovariectomized rat pituitary mRNA, the start of transcription was determined to be 7 bp upstream from the start of translation. Characteristic promoter elements are present in the 5‘-flanking region of the gene, including the Goldberg-Hogness sequence, TATAAA, 31 bp, and the consensus CAAT box sequence, 167 bp upstream from the start of transcription, respectively. Within the proximal 200 bp flanking the 5‘-region of the transcriptional unit, there is strong homology between the rat and human LH beta genes, suggesting that these regions include sequences which may be important for regulation of gene expression. Isolation and characterization of the rat LH beta gene further defines the evolution of glycoprotein hormone genes and will facilitate the study of cellular and molecular mechanisms which regulate LH beta gene expression.