EFFECT OF CONFLUENT HOLDING ON POTENTIALLY LETHAL DAMAGE REPAIR, CELL-CYCLE PROGRESSION, AND CHROMOSOMAL-ABERRATIONS IN HUMAN NORMAL AND ATAXIA-TELANGIECTASIA FIBROBLASTS
EFFECT OF CONFLUENT HOLDING ON POTENTIALLY LETHAL DAMAGE REPAIR, CELL-CYCLE PROGRESSION, AND CHROMOSOMAL-ABERRATIONS IN HUMAN NORMAL AND ATAXIA-TELANGIECTASIA FIBROBLASTS
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DOI：
10.2307/3576305
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发表时间：
1985-01-01
影响因子：
3.4
通讯作者：
NAGASAWA, H
中科院分区：
文献类型：
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作者：
LITTLE, JB;NAGASAWA, H
在密度抑制生长期间，检查了经X射线照射的人二倍体成纤维细胞继代培养后，融合保持恢复对存活率、染色体畸变和整个生命周期进展的影响。测定了3个正常菌株的反应，并与4个共济失调-毛细血管扩张症（AT）、一个AT杂合子和2个遗传性视网膜母细胞瘤菌株的反应进行了比较。潜在致死性损伤修复（PLDR）的能力略有减少，在视网膜母细胞瘤细胞和AT细胞几乎没有，但正常的AT杂合子。在AT细胞中不存在融合保持期间在正常细胞中观察到的染色体畸变下降，这与缺乏PLDR一致。继代培养后，所有经辐照的AT成纤维细胞均通过细胞周期进展至第1次有丝分裂，无延迟。与正常细胞相比，AT杂合子和视网膜母细胞瘤细胞的DNA合成起始延迟增强，并且大部分细胞在G1期被不可逆地阻断。汇合保持减少了延迟进入S和G1。AT纯合子和杂合子细胞对X射线的反应明显不同。
The effects of confluent holding recovery on survival, chromosomal aberrations, and progression through the life cycle after subculture of human diploid fibroblasts X-irradiated during density inhibition of growth were examined. The responses of 3 normal strains were determined and compared with those of 4 ataxia-telangiectasia (AT), an AT heterozygote, and 2 heriditary retinoblastoma strains. The capacity for potentially lethal damage repair (PLDR) was slightly reduced in retinoblastoma cells and almost absent in AT cells, but normal in an AT heterozygote. The decline in chromosomal aberrations seen in normal cells during confluent holding was absent in AT cells, consistent with the lack of PLDR. Following subculture, all irradiated AT fibroblasts progressed through the cell cycle to the 1st mitosis with no delay. AT heterozygotic and retinoblastoma cells showed both an enhanced delay in the initiation of DNA synthesis and a large fraction of cells irreversibly blocked in G1 as compared with normal cells. Both the delayed entry into S and the G1 were reduced by confluent holding. AT homozygotic and heterozygotic cells evidently respond quite differently to X irradiation.