Esposito F, Russo T, Ammendola R, Duilio A, Salvatore F, Cimino F
Cancer Res. 1985 Dec;45(12 Pt 1):6260-3.
To evaluate the relationship between pseudouridine increase in biological fluids and retroviral cell transformation, we have studied the effect of retrovirus infection and/or transformation on the rate of pseudouridine excretion by chick embryo fibroblasts. The results show that: pseudouridine excretion by chick embryo fibroblasts transformed by Rous sarcoma virus is several times higher than that of normal cells; this increased excretion precedes by many hours the appearance of the morphological signs of transformation and it is always present when neosynthesized infectious viral particles are released into the culture medium; and pseudouridine excretion was also increased in cells infected by a mutant of Rous sarcoma virus (RAV-1) which, lacking the src gene, does not transform the cells but replicates normally. To investigate if pseudouridine overproduction is related to an altered turnover rate of specific transfer RNA (tRNA) species which functions as primer of retrovirus reverse transcriptase, the concentration of non-acylated proline-accepting tRNA and non-acylated tryptophan-accepting tRNA, primers of reverse transcriptase of murine leukemia virus and of Rous sarcoma virus, respectively, has been measured, the former in normal and transformed AKR thymus and the latter in normal fibroblasts and in fibroblasts infected by Rous sarcoma virus or by its nontransforming mutant. The results show that in both systems a significant increase of the primer tRNA species occurs in the infected or transformed cells.
为了评估生物体液中假尿苷增加与逆转录病毒细胞转化之间的关系，我们研究了逆转录病毒感染和/或转化对鸡胚成纤维细胞假尿苷排泄率的影响。结果表明：经劳氏肉瘤病毒转化的鸡胚成纤维细胞的假尿苷排泄量比正常细胞高出数倍；这种排泄增加在转化的形态学迹象出现前数小时就已发生，并且当新合成的感染性病毒颗粒释放到培养基中时，它总是存在；被劳氏肉瘤病毒（RAV - 1）突变体感染的细胞中假尿苷排泄也增加了，该突变体缺乏src基因，不转化细胞但能正常复制。为了研究假尿苷过量产生是否与作为逆转录病毒逆转录酶引物的特定转移RNA（tRNA）种类的周转率改变有关，分别测量了非酰化脯氨酸接受性tRNA和非酰化色氨酸接受性tRNA的浓度，前者分别在正常和转化的AKR胸腺中，后者在正常成纤维细胞以及被劳氏肉瘤病毒或其非转化突变体感染的成纤维细胞中。结果表明，在这两个系统中，引物tRNA种类在感染或转化的细胞中均显著增加。
