Nucleotide sequence analysis of c-raf-1 cDNA and promoter from a radiation-resistant human squamous carcinoma cell line: deletion within exon 17.
Nucleotide sequence analysis of c-raf-1 cDNA and promoter from a radiation-resistant human squamous carcinoma cell line: deletion within exon 17.
复制标题
抗辐射人鳞状癌细胞系的 c-raf-1 cDNA 和启动子的核苷酸序列分析：外显子 17 内的缺失。
DOI：
10.1002/mc.2940080105
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发表时间：
1993
影响因子：
4.6
通讯作者：
Kasid,U
中科院分区：
文献类型：
--
作者：
Patel,BK;Kasid,U
c-raf-1原癌基因是v-raf的细胞同源物，v-raf是急性转化逆转录病毒3611-MSV的癌基因。c-raf-1（raf-1）的产物是一种74 kDa的细胞质丝氨酸/苏氨酸蛋白激酶。我们以前报道过，反义人c-raf-1 cDNA转染导致内源性c-raf-1转录物减少，肿瘤生长速率降低，并增强了从放射抗性喉鳞状细胞癌建立的SQ-20 B肿瘤细胞的放射敏感性。在本文报道的研究中，我们使用cDNA连接的聚合酶链反应扩增和核苷酸测序来检查3233-bp SQ-20 B c-raf-1 cDNA的结构。通过基因组DNA扩增分析812-bp c-raf-1启动子区，然后进行克隆和测序。与先前发表的c-raf-1序列的序列比较表明SQ-20 B c-raf-1的编码区内没有结构变化。然而，在外显子17内的3′非翻译区观察到4-bp缺失。这种缺失也存在于从SQ-20 B cDNA文库分离的c-raf-1 cDNA克隆中。虽然不能排除3′转录调控机制的可能性，但似乎raf-1蛋白激酶可能通过与损伤和修复相关信号转导途径中的其他分子相互作用来调节放射抗性恶性肿瘤的发展。© 1993 Wiley利斯公司
The c‐raf‐1 proto‐oncogene is the cellular homologue of v‐raf, the oncogene of the acutely transforming retrovirus 3611‐MSV. The product of c‐raf‐1 (raf‐1) is a 74‐kDa cytoplasmic serine/threonine protein kinase. We previously reported that antisense human c‐raf‐1 cDNA transfection results in reduction of the endogenous c‐raf‐1 transcript, decreased tumor growth rate, and enhanced radiation sensitivity of SQ‐20B tumor cells established from a radiation‐resistant laryngeal squamous cell carcinoma. In the study reported here, we used cDNA‐linked polymerase chain reaction amplification and nucleotide sequencing to examine the structure of the 3233‐bp SQ‐20B c‐raf‐1 cDNA. The 812‐bp c‐raf‐1 promoter region was analyzed by genomic DNA amplification followed by cloning and sequencing. Sequence comparison with a previously published c‐raf‐1 sequence indicated no structural changes within the coding region of SQ‐20B c‐raf‐1. However, a 4‐bp deletion was observed in the 3′ untranslated region within exon 17. This deletion was also present in a c‐raf‐1 cDNA clone isolated from a SQ‐20B cDNA library. While the possibility of a 3′ transcriptional control mechanism cannot be ruled out, it appears that the raf‐1 protein kinase may regulate the development of radioresistant malignancies via interaction with other molecules in the damage and repair—related signal transduction pathways. © 1993 Wiley‐Liss, Inc.