Daoud A H, Griffin A C
Cancer Res. 1976 Aug;36(8):2885-90.
A highly purified phenylalanine transfer RNA (tRNAPhe) was isolated from a normal rat liver and from livers of male and female rats fed a semisynthetic diet containing 0.06% 3'-methyl-4-dimethylaminoazobenzene for 3 weeks. Absorption spectral analysis on tRNAPhe from normal and carcinogen-fed rats indicated an unusual absorption above 335 nm by tRNAPhe isolated from the latter group. Ribonuclease T1 digestion followed by chromatography on diethylaminoethyl cellulose columns indicated the existence of a major peak of covalently bound oligonucleotide-azo complex. Microcrystalline cellulose thin-layer chromatography resolved the peak into one major and four minor components, all with similar absorption spectra. Enzymatic digestion of the major peak obtained from diethylaminoethyl cellulose chromatography to ribonucleosides, followed by chromatography on cellulose thin layer, resulted in one major and three minor components. A higher uridine:cytidine base ratio was also observed in the tRNAPhe isolated from the carcinogenfed animals. These findings suggest that certain transfer RNA's may be major targets for this azo carcinogen.
从正常大鼠肝脏以及喂食含0.06% 3'-甲基-4-二甲基氨基偶氮苯的半合成饮食3周的雄性和雌性大鼠肝脏中分离出高度纯化的苯丙氨酸转移RNA（tRNAPhe）。对正常大鼠和喂食致癌物大鼠的tRNAPhe进行吸收光谱分析表明，从后一组分离出的tRNAPhe在335nm以上有异常吸收。核糖核酸酶T1消化后在二乙氨基乙基纤维素柱上进行层析，表明存在一个共价结合的寡核苷酸-偶氮复合物的主峰。微晶纤维素薄层层析将该峰分离为一个主要成分和四个次要成分，所有成分的吸收光谱相似。将从二乙氨基乙基纤维素层析获得的主峰酶解为核糖核苷，然后在纤维素薄层上进行层析，得到一个主要成分和三个次要成分。在从喂食致癌物的动物中分离出的tRNAPhe中也观察到较高的尿苷：胞苷碱基比。这些发现表明，某些转移RNA可能是这种偶氮致癌物的主要靶标。
