Axenovich S A, Kazarov A R, Boiko A D, Armin G, Roninson I B, Gudkov A V
Department of Molecular Genetics, University of Illinois at Chicago, 60607, USA.
Cancer Res. 1998 Aug 1;58(15):3423-8.
The motor protein kinesin is a tetramer consisting of two heavy and two light chains. Expression of an antisense RNA fragment derived from the mouse ubiquitous kinesin heavy chain (uKHC) cDNA is associated with a unique type of multidrug resistance. We analyzed the effects of retroviral transduction of the human uKHC and its derivatives on drug sensitivity of the human fibrosarcoma cell line HT1080. Surprisingly, overexpression of full-length uKHC and its variants that were deficient in the NH2-terminal motor domain produced a phenotype similar to that of antisense RNA, characterized by resistance to etoposide and collateral sensitivity to colchicine. This altered drug response, therefore, appears to be a general consequence of kinesin deregulation. The genetic suppressor element approach was applied to map the determinants of drug response in the kinesin heavy chain. A sense-oriented genetic suppressor element conferring resistance to etoposide was isolated from a retroviral library of randomly fragmented uKHC cDNA. This element encodes the last 55 amino acids of uKHC, suggesting that the COOH-terminal tail domain of uKHC is involved in the cellular drug response.
运动蛋白驱动蛋白是一种由两条重链和两条轻链组成的四聚体。源自小鼠遍在驱动蛋白重链（uKHC）cDNA的反义RNA片段的表达与一种独特类型的多药耐药性相关。我们分析了逆转录病毒转导人uKHC及其衍生物对人纤维肉瘤细胞系HT1080药物敏感性的影响。令人惊讶的是，全长uKHC及其在NH2末端运动结构域缺失的变体的过表达产生了与反义RNA相似的表型，其特征为对依托泊苷耐药和对秋水仙碱有旁侧敏感性。因此，这种改变的药物反应似乎是驱动蛋白失调的普遍结果。应用遗传抑制元件方法来定位驱动蛋白重链中药物反应的决定因素。从随机片段化的uKHC cDNA的逆转录病毒文库中分离出一种赋予对依托泊苷耐药性的正义导向遗传抑制元件。该元件编码uKHC的最后55个氨基酸，表明uKHC的COOH末端尾部结构域参与细胞的药物反应。
