Rat brain expresses a heterogeneous family of calcium channels.
Rat brain expresses a heterogeneous family of calcium channels.
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大鼠大脑表达异质钙通道家族。
DOI：
10.1073/pnas.87.9.3391
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发表时间：
1990
影响因子：
11.1
通讯作者：
Davidson,N
中科院分区：
文献类型：
--
作者：
Snutch,TP;Leonard,JP;Gilbert,MM;Lester,HA;Davidson,N
我们描述了几个大鼠脑cDNA的分离和表征，是同源的心脏和骨骼肌二氢吡啶敏感的钙通道的α 1亚基。对32个cDNA的北方印迹分析表明，它们可以分为四个不同的类别（A、B、C和D），每个类别对应于脑mRNA的不同杂交模式。Southern杂交和DNA测序表明，每一类cDNA代表一个不同的基因或基因家族。在测序的区域中，大鼠脑C类和D类基因产物与兔骨骼肌Ca通道共享约75%的氨基酸同一性。此外，C类多肽与兔心脏Ca通道几乎相同（97%同一性）。相比之下，大鼠脑A类和B类cDNA与二氢吡啶敏感性Ca通道（47-64%氨基酸同一性）以及脑C类和D类基因（51-55%氨基酸同一性）更远相关。为了检查分离的脑cDNA的功能意义，在爪蟾卵母细胞中进行杂交耗竭实验。反义寡核苷酸对A类和B cDNA的每一个部分抑制，和C类寡核苷酸几乎完全抑制，在大鼠脑mRNA注射卵母细胞中的Ba电流的表达，但没有寡核苷酸影响的电压门控Na或K电导的表达。克隆表征和测序结果表明，一些不同的，但相关的，电压门控钙通道基因在大脑中表达。反义寡核苷酸实验特别表明，一个或几个钙通道类相关的大鼠脑mRNA注射的卵母细胞中观察到的钙通道。
We describe the isolation and characterization of several rat brain cDNAs that are homologous to the alpha 1 subunit of heart and skeletal muscle dihydropyridine-sensitive Ca channels. Northern blot analysis of 32 cDNAs shows that they can be grouped into four distinct classes (A, B, C, and D), each corresponding to a distinct hybridization pattern of brain mRNAs. Southern blot and DNA sequencing suggest that each class of cDNA represents a distinct gene or gene family. In the regions sequenced, the rat brain class C and D gene products share approximately 75% amino acid identity with the rabbit skeletal muscle Ca channel. In addition, the class C polypeptide is almost identical to the rabbit cardiac Ca channel (97% identity). In contrast, the rat brain class A and B cDNAs are more distantly related to dihydropyridine-sensitive Ca channels (47-64% amino acid identity) and to the brain class C and D genes (51-55% amino acid identity). To examine the functional significance of the isolated brain cDNAs, hybrid depletion experiments were performed in Xenopus oocytes. Antisense oligonucleotides against class A and B cDNAs each partially inhibited, and a class C oligonucleotide almost fully inhibited, the expression of Ba current in rat brain mRNA injected oocytes; but none of the oligonucleotides affected the expression of voltage-gated Na or K conductances. The clone characterization and sequencing results demonstrate that a number of distinct, yet related, voltage-gated Ca-channel genes are expressed in the brain. The antisense oligonucleotide experiments specifically show that one or several of the Ca-channel classes are related to the Ca channels observed in rat brain mRNA injected oocytes.