Primary structure of the rat kidney band 3 anion exchange protein deduced from a cDNA.
Primary structure of the rat kidney band 3 anion exchange protein deduced from a cDNA.
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DOI：
10.1016/s0021-9258(18)83167-2
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发表时间：
1989-05
期刊：
影响因子：
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通讯作者：
Katarzyna E. Kudrycki;G. Shull
中科院分区：
文献类型：
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作者：
Katarzyna E. Kudrycki;G. Shull
使用来自小鼠红细胞带3 Cl−/HCO 3 −交换器的氨基酸序列的寡核苷酸杂交探针筛选大鼠肾脏cDNA文库。分离出10个代表一类mRNA并编码肾带3阴离子交换剂的cDNA。推导的氨基酸序列分析表明，肾带3是红细胞带3的截短版本。848个氨基酸的大鼠肾脏蛋白质实际上与小鼠红细胞带3相同，除了它缺少N-末端胞质结构域的前79个氨基酸。红细胞带3 mRNA中包含的带3基因的外显子1、2和3不存在于肾cDNA中。肾带3转录物的5′-非翻译区包含来自带3基因的第三内含子和外显子4和5的序列。在大鼠肾脏mRNA中作为非翻译序列的外显子4和5的序列有可能编码红细胞带3的氨基酸46-79，但不是开放阅读框的一部分;表观翻译起始位点对应于小鼠红细胞带3 mRNA的密码子80。北方印迹杂交研究表明，另外两个条带3 mRNA在肾脏和大脑中以低水平表达，这两个条带3 mRNA在大小上与肾脏中的主要4.5-β-淀粉酶对转录物不同。
A rat kidney cDNA library was screened using an oligonucleotide hybridization probe derived from an amino acid sequence of the mouse erythrocyte Band 3 Cl−/HCO3−exchanger. Ten cDNAs representing a single class of mRNA and encoding the kidney Band 3 anion exchanger were isolated. Analysis of the deduced amino acid sequence revealed that kidney Band 3 is a truncated version of erythrocyte Band 3. The 848-amino acid rat kidney protein is virtually identical to mouse erythrocyte Band 3 except that it lacks the first 79 amino acids of the N-terminal cytoplasmic domain. Exons 1, 2, and 3 of the Band 3 gene, which are included in erythrocyte Band 3 mRNA, are not present in the kidney cDNA. The 5′-untranslated regions of kidney Band 3 transcripts contain sequences from the third intron and exons 4 and 5 of the Band 3 gene. The sequences from exons 4 and 5 that serve as untranslated sequences in the rat kidney mRNA have the potential to encode amino acids 46–79 of erythrocyte Band 3 but are not part of an open reading frame; the apparent translation initiation site corresponds to codon 80 of mouse erythrocyte Band 3 mRNA. Northern blot hybridization studies indicate that two additional Band 3 mRNAs, which differ in size from the major 4.5-kilobase pair transcript in kidney, are expressed at low levels in kidney and brain.