Hydropathy Profiles of Predicted Thyrotropin‐Releasing Hormone Precursors are Highly Conserved Despite Low Similarity of Primary Structures
Hydropathy Profiles of Predicted Thyrotropin‐Releasing Hormone Precursors are Highly Conserved Despite Low Similarity of Primary Structures
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尽管一级结构相似性较低，但预测的促甲状腺素释放激素前体的水病特征高度保守
DOI：
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发表时间：
1996
影响因子：
3.2
通讯作者：
A. Urano
中科院分区：
文献类型：
--
作者：
Akira Ohide;H. Ando;T. Yanagisawa;A. Urano
通过逆转录聚合酶链式反应 (RT-PCR) 从红鲑鱼的下丘脑 mRNA 中扩增出两种编码促甲状腺素释放激素 (TRH) 前体的 cDNA（TRH-A 和 TRH-B）。使用对应于 TRH 祖序列 (Lys/Arg-Arg-Gln-His-Pro-Gly-Lys/Ag-Arg) 的两个引物实现扩增。通过5'-和3'-RACE方法获得编码TRH-A的全长cDNA。它的长度为 1324 个碱基对 (bp)，包含 5' 和 3' 非翻译区序列以及 259 个密码子的开放阅读框。从核苷酸序列推断出的红鲑TRH-A串联含有8个TRH祖序列拷贝。另一种编码TRH-B部分的cDNA由242 bp组成，TRH-A和TRH-B cDNA之间的序列同源性为90%。红鲑鱼和马苏鲑鱼基因组 DNA 的 Southern 印迹分析结果支持了鲑鱼中至少存在两个 TRH 基因的证据。对红鲑鱼不同组织中 TRH 基因表达的 RT-PCR 分析表明，仅在大脑中观察到强表达。红鲑鱼 TRH-A 的一级结构与人类、大鼠和非洲爪蟾 TRH 前体的相似性较低（分别为 35%、27% 和 44%）。然而，它们的亲水特性几乎彼此相同。红鲑鱼 TRH-A 的剖面显示存在两个离散的疏水区域，一个位于对应于信号肽的 N 末端区域，另一个位于 C 末端区域。所有重复的 TRH 祖序列都包含在三个易于识别的亲水区域中。因此，目前的结果表明，尽管 TRH 前体的一级结构在脊椎动物的进化途径中发生了分化，但 TRH 前体的三维结构是高度保守的。
Two types of cDNAs encoding thyrotropin‐releasing hormone (TRH) precursors (TRH‐A andTRH‐B) were amplified from hypothalamic mRNA of sockeye salmon by reverse transcriptase‐polymerase chain reaction (RT‐PCR). The amplification was achieved using two primers which correspond to TRH progenitor sequence (Lys/Arg‐Arg‐Gln‐His‐Pro‐Gly‐Lys/Ag‐Arg). A full length cDNA encoding TRH‐A was obtained by 5′‐ and 3′‐RACE methods. It has a length of 1324 base pairs (bp) that contains sequences of 5′ and 3′ untranslated regions and an open reading frame of 259 codons. The sockeye salmon TRH‐A deduced from the nucleotide sequence tandemly contains 8 copies of TRH progenitor sequences. Another cDNA which encodes a part of TRH‐B consists of 242 bp, and the sequence homology between TRH‐A and ‐B cDNAs is 90%. The result of Southern blot analysis of sockeye and masu salmon genomic DNAs supported the evidence that there are at least two TRH genes in the salmonid. A RT‐PCR analysis of TRH gene expression in various tissues of sockeye salmon showed that strong expression was observed only in the brain. The primary structure of the sockeye salmon TRH‐A shares low similarity to those of human, rat and Xenopus TRH precursors (35, 27 and 44%, respectively). However, their hydropathy profiles were almost the same with each other. The profile of sockeye salmon TRH‐A showed the presence of two discrete hydrophobic regions, one in the N‐terminal region which corresponds to the signal peptide and the other in the C‐terminal region. All of the repetitive TRH progenitor sequences are included in three hydrophilic regions easily recognizable. The present results thus suggest that the three‐dimensional structures of TRH precursors are highly conserved, although the primary structures of TRH precursors have diverged through the evolutionary pathway of vertebrates.
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DOI：
10.1073/pnas.85.23.8998
发表时间：
1988-12-01
影响因子：
11.1
作者：
FROHMAN, MA;DUSH, MK;MARTIN, GR
通讯作者：
MARTIN, GR
影响因子：
56.9
作者：
LECHAN, RM;WU, P;GOODMAN, RH
通讯作者：
GOODMAN, RH
编码人前促甲状腺素释放激素的人基因组 DNA 和下丘脑 cDNA 的克隆和结构。
DOI：
10.1210/mend-4-4-551
发表时间：
1990
期刊：
Molecular endocrinology (Baltimore, Md.)
影响因子：
--
作者：
Yamada,M;Radovick,S;Wondisford,FE;Nakayama,Y;Weintraub,BD;Wilber,JF
通讯作者：
Wilber,JF
高分子量大鼠胰岛素样生长因子结合蛋白 (IGF-BP3) 的互补 DNA 结构及其 mRNA 的组织分布。
DOI：
10.1016/s0006-291x(89)80052-x
发表时间：
1989
影响因子：
3.1
作者：
Shimasaki,S;Koba,A;Mercado,M;Shimonaka,M;Ling,N
通讯作者：
Ling,N