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Mechanisms involved in loss of PI-anchored proteins (DAF and CD59) in human leukemia cell lines.

人类白血病细胞系中 PI 锚定蛋白（DAF 和 CD59）丢失的机制。

基本信息

批准号：
05671933
负责人：
HATANAKA Michiyo
金额：
$ 1.41万
依托单位：
Osaka Medical College
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1995
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05671933/
关键词：
Complement ragulatory-proteins PI-anchored proteins DAF CD59 mRNA Marignancy Human leukemia cell lines Transfection シグナル伝達チロシンキナーゼ架橋カベオリン PIアンカー PNH transfection GPIアンカー

项目摘要

We investigated the mechanisms of defects of glycosyl-phosphatidylinositol (GPI) -anchored complement regulatory proteins, DAF and/or CD59, in a panel of human leukemia cell lines that lack surface expression of these proteins : U937 (DAF^+/CD59^-), CEM (DAF^<-E1S1+>), TALL (DAF^-/CD59^-), and a substrains of Ramos [Ramos (-)] (DAF^-/CD59^-), Northe blot and reverse transcriptase-polymerase chain reaction (RT-PCR) revealed that the main cause of the DAF and/or CD59 deficiency is the failure of mRNA expression in most of the cell lines except for Ramos (-) which allowed the generation of the sufficient mRNA of DAF and CD59 U937, CEM,and TALL cells were not defective in GPI anchor formation as assesse by the detection of other GPI-anchored proteins. No gene abnormality corresponding to DAF or CD59 was detected by Southern blotting. Thus, the cause of the defects of DAF and/CD59 in these leukemia cell lines except for Ramos (-) is virtually undetectable steady state levels of the relevant mRNA,most likely, is attributable to aberrance at the transcription steps in these cell lines. On the other hand, Ramos (-) cells failed to generate a GPI anchor, whereas it normally expressed DAF and CD59 transcripts. The transfection of PIGA cDNA to Ramos (-) cells restored the DAF and CD59 expression, indicating that the mechanism defective in GPI-anchor formation is similar to that of paroxysmal nocturnal hemoglobinuria (PNH) cells, a deficiency of the PIG-A gene product. Thus, the mechanisms of the defects of DAF and/or CD59 in human leukemia cell lines are not uniform and are mostly different from that proposed to cause PNH.

我们研究了糖基-磷脂酰肌醇（GPI）锚定的补体调节蛋白，CD 49和/或CD 59的缺陷机制，在一组缺乏这些蛋白表面表达的人白血病细胞系中：U937（CD59 ^+/CD59^-），CEM（^<-E1 S1 +>），高（CD ^-/CD 59 ^-）和拉莫斯亚株[拉莫斯（-）]（CD59 ^-/CD59^-），Northern杂交和逆转录-聚合酶链反应（RT-PCR）结果表明，引起大肠癌的主要原因是大肠癌的发生和/或大肠癌的发生。或CD 59缺陷是在除了拉莫斯（-）以外的大多数细胞系中mRNA表达的失败，其允许产生足够的CD 59和CD 59的mRNA U937，CEM，通过检测其他GPI锚定蛋白，TALL细胞在GPI锚形成方面没有缺陷，这与阿塞塞的检测一致。Southern杂交未检测到CD 59和CD 10基因异常。因此，除了拉莫斯（-）以外，这些白血病细胞系中β-CD和/CD 59缺陷的原因实际上是相关mRNA的不可检测的稳态水平，最可能的是，可归因于这些细胞系中转录步骤的异常。另一方面，拉莫斯（-）细胞不能产生GPI锚，而它通常表达CD 59和CD 59转录本。将PIGA cDNA转染到拉莫斯（-）细胞中恢复了GPI和CD 59的表达，表明GPI锚形成缺陷的机制与阵发性睡眠性血红蛋白尿症（PNH）细胞的机制相似，PIG-A基因产物的缺陷。因此，在人类白血病细胞系中的CD 59和/或CD 59的缺陷的机制是不统一的，并且大多数与所提出的引起PNH的机制不同。