Study of synergistic effects among different environmental mutagens in the stamen hairs of Tradescantia

本研究于1996 ~ 1998年采用紫露草无性系BNL 4430的雄蕊-毛系统，研究了（1）烷化剂的致突变性及其与X射线的诱变增效作用，（2）烷化剂间的诱变增效作用，（3）前诱变剂的致突变性及其与X射线的诱变相互作用，（4）前诱变剂和烷化剂之间的诱变相互作用。(1)本文测定了N-乙基-N-亚硝基脲（ENU）、硫酸二乙酯（DES）和1，2-二溴乙烷（EDB）的致突变性，以及甲磺酸乙酯（EMS）、甲磺酸甲酯（MMS）、硫酸二甲酯（DMS）和N-甲基-N-亚硝基脲（MNU）的致突变性。ENU、DES、EDB与EMS、MMS、DMS具有协同作用。(2)MNU与EMS之间仅存在相加作用，而MMS与EMS之间存在协同作用。(3)测定了邻苯二胺（PDA）、N-亚硝基二甲胺（DMN）和双官能烷化剂EDB的致突变性，发现PDA和DMN在X射线照射后与X射线协同作用，而在X射线照射前与X射线拮抗作用，与马来酰肼（MH）相似。然而，PDA和DMN分别与X射线协同和相加，当X射线在PDA和DMN处理期间，表明不同的时间段所需的过氧化物酶激活。(4)发现MH和EMS总是起拮抗作用。

This study was carried out in 1996 to 1998, using the stamen-hair system of Tradescantia clone BNL 4430, in order to investigate (1) the mutagenicities of alkylating agents and their mutagenic synergisms with X rays, (2) the mutagenic synergisms among alkylating agents, (3) the mutagenicities of promutagens and their mutagenic interactions with X rays, and (4) the mutagenic interactions between promutagens and alkylating agents.(1) The mutagenicities of N-ethyl-N-nitrosourea (ENU), diethyl sulfate (DES) and 1 , 2-dibromoethane (EDB) were determined, adding to those determined earlier for ethyl methanesulfonate (EMS), methyl methanesulfonate (MMS), dimethyl sulfate (DMS) and N-methyl-N-nitrosourea (MNU). ENU, DES and EDB all acted synergistically with X rays, as EMS, MMS and DMS did. (2) MNU acted merely additively with EMS, differing from MMS and EMS which acted synergistically. (3) The mutagenicities of o-phenylenediamine (PDA), N-nitrosodimethylamine (DMN) and EDB (also a bitunctional alkylating agent) were determined, and PDA and DMN were found to act synergistically with X rays when treated after exposing to X rays but antagonistically when treated before exposing to X rays, similarly to maleic hydrazide (MH) studed earlier. However, PDA and DMN acted synergistically and additively with X rays, respectively, when X-rayed during PDA and DMN treatments, indicating different time periods needed for their activations by peroxidase. (4) MH and EMS were found to act always antagonistically.