The cell proliferation-associated antigen of antibody Ki-67: a very large, ubiquitous nuclear protein with numerous repeated elements, representing a new kind of cell cycle-maintaining proteins.
The cell proliferation-associated antigen of antibody Ki-67: a very large, ubiquitous nuclear protein with numerous repeated elements, representing a new kind of cell cycle-maintaining proteins.
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抗体KI-67的细胞增殖相关抗原：一种非常大的，无处不在的核蛋白，具有许多重复的元素，代表了一种新型的细胞周期维护蛋白。
DOI：
10.1083/jcb.123.3.513
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发表时间：
1993-11
影响因子：
7.8
通讯作者：
Gerdes, J
中科院分区：
文献类型：
--
作者：
Schluter, C;Duchrow, M;Wohlenberg, C;Becker, M H;Key, G;Flad, H D;Gerdes, J
由单抗Ki-67定义的抗原是一种人类核蛋白，其表达与细胞增殖密切相关，在常规病理学中被广泛用作衡量人类肿瘤细胞生长分数的增殖标记物。Ki-67在增殖细胞蛋白质免疫印迹中检测到一条表观分子量分别为395和345kD的双带。我们克隆并测序了该细胞增殖相关蛋白的全长cDNA2个差异剪接异构体，开放阅读框分别为9,768和8,688个碱基，计算出其相对分子质量分别为358,761D和319,508 D。新的抗细菌表达部分的单抗和由分离的cDNA合成的多肽与天然的Ki-67抗原发生反应，从而提供了一系列证据，证明我们已经克隆了真正的Ki-67抗原的cDNA。Ki-67抗原基因的中央部分含有一个6845bp的大外显子，由16个重复的366个碱基组成，每一个都包含一个高度保守的66个碱基的新基序，即“Ki-67基序”，它编码了Ki-67检测到的表位。对Ki-67抗原的核酸和推导的氨基酸序列的计算机分析证实，该基因编码的是一种核蛋白和短命蛋白，与已知序列没有任何显著的同源性。Ki-67抗原特异性反义寡核苷酸抑制IM-9细胞的增殖，提示Ki-67抗原可能是维持细胞增殖的绝对必要条件。我们得出结论，Ki-67抗原定义了一种新的与细胞周期相关的核非组蛋白。
The antigen defined by mAb Ki-67 is a human nuclear protein the expression of which is strictly associated with cell proliferation and which is widely used in routine pathology as a "proliferation marker" to measure the growth fraction of cells in human tumors. Ki-67 detects a double band with apparent molecular weights of 395 and 345 kD in immunoblots of proteins from proliferating cells. We cloned and sequenced the full length cDNA, identified two differentially spliced isoforms of mRNA with open reading frames of 9,768 and 8,688 bp encoding for this cell proliferation-associated protein with calculated molecular weights of 358,761 D and 319,508 D, respectively. New mAbs against a bacterially expressed part and a synthetic polypeptide deduced from the isolated cDNA react with the native Ki-67 antigen, thus providing a circle of evidence that we have cloned the authentic Ki-67 antigen cDNA. The central part of the Ki-67 antigen cDNA contains a large 6,845-bp exon with 16 tandemly repeated 366-bp elements, the "Ki-67 repeats", each including a highly conserved new motif of 66 bp, the "Ki-67 motif", which encodes for the epitope detected by Ki-67. Computer analysis of the nucleic acid and the deduced amino acid sequence of the Ki-67 antigen confirmed that the cDNA encodes for a nuclear and short-lived protein without any significant homology to known sequences. Ki-67 antigen-specific antisense oligonucleotides inhibit the proliferation of IM-9 cell line cells, indicating that the Ki-67 antigen may be an absolute requirement for maintaining cell proliferation. We conclude that the Ki-67 antigen defines a new category of cell cycle-associated nuclear nonhistone proteins.