不同传能线密度的电离辐射诱导的次黄嘌呤磷酸核糖转移酶（HPRT）突变亚克隆的染色体不稳定性

Chromosome instability of HPRT-mutant subclones induced by ionising radiation of various LET.

作者信息

Govorun R D, Koshlan I V, Koshlan N A, Krasavin E A, Shmakova N L

机构信息

Joint Institute for Nuclear Research (JINR), Division of Radiation and Radiobiological Research (DRRR), Dubna, Moscow region, Russia.

出版信息

Adv Space Res. 2002;30(4):885-90. doi: 10.1016/s0273-1177(02)00407-6.

DOI:10.1016/s0273-1177(02)00407-6

PMID:12539752

Abstract

The induction of HPRT-mutations and survival of Chinese hamster cells (line B11ii-FAF28, clone 431) were studied after irradiation by 4He and 12C-ions of various LET (20-360 keV/micrometers), produced by the U-200 heavy ion accelerator. The RBE increases with LET up to the maximum at 100-200 keV/micrometers and then decreases. Cytogenetic analysis was performed on the HPRT-mutant subclones selected from unirradiated Chinese hamster V-79 cells and from HPRT-mutant subclones that arose after exposure to gamma-rays, 1 GeV protons and 14N-ions (LET-77 keV/micrometers), produced by the synchrophasotron and the U-400M heavy ion accelerator. Slow growing mutant subclones were observed. The cytogenetic properties of individual clones were highly heterogeneous and chromosome instability was observed in both spontaneous and radiation-induced mutants. Chromosome instability was highest among spontaneous mutants and decreased with increasing LET.

摘要

利用U - 200重离子加速器产生的不同传能线密度（LET，20 - 360 keV/μm）的4He和12C离子，对中国仓鼠细胞（B11ii - FAF28系，431克隆）进行照射后，研究了次黄嘌呤 - 鸟嘌呤磷酸核糖转移酶（HPRT）突变的诱导及细胞存活情况。相对生物效应（RBE）随LET升高，在100 - 200 keV/μm时达到最大值，然后下降。对从未经照射的中国仓鼠V - 79细胞以及经γ射线、1 GeV质子和同步稳相加速器及U - 400M重离子加速器产生的14N离子（LET - 77 keV/μm）照射后产生的HPRT突变亚克隆进行了细胞遗传学分析。观察到生长缓慢的突变亚克隆。单个克隆的细胞遗传学特性高度异质，在自发突变体和辐射诱导的突变体中均观察到染色体不稳定性。染色体不稳定性在自发突变体中最高，并随LET增加而降低。