Klemenz R, Reinhardt M, Diggelmann H
Mol Biol Rep. 1981 May 22;7(1-3):123-6. doi: 10.1007/BF00778742.
70S RNA has been prepared from mouse mammary tumor virus (MMTV) produced by the GR tumor cell line. After denaturation for 3 min at 60 degrees C the RNA was applied to a sucrose gradient and molecules sedimenting between 10-16S were selected and passed over an oligo-dT cellulose column. The poly A containing RNA fraction was used as a template for the synthesis of complementary DNA with reverse transcriptase in the presence of dideoxynucleoside triphosphates. Oligo-nucleotides p(dT)7rG, p(dT)7rA and (p(dT)7rC were tested for their primer activity. Two of the three primers gave readable sequences. This suggests a heterogeneity in the 3' end of the viral RNA, a phenomenon also observed with avian retroviruses. Nucleotides 37-45 from the 3' end are made up of only A's and T's and resemble a Hogness box. This finding could have biological consequences for the transcription of proviral DNA in the unintegrated and integrated state. Instead of the usual AAUAAA sequence present in mRNA's close and in front of the site of polyadenylation we find a sequence AGUAAA.
已从GR肿瘤细胞系产生的小鼠乳腺肿瘤病毒（MMTV）中制备出70S RNA。在60℃下变性3分钟后，将RNA应用于蔗糖梯度，选择沉降在10 - 16S之间的分子，并使其通过寡聚dT纤维素柱。含有聚A的RNA部分用作模板，在双脱氧核苷三磷酸存在下用逆转录酶合成互补DNA。测试了寡核苷酸p(dT)7rG、p(dT)7rA和(p(dT)7rC的引物活性。三种引物中的两种给出了可读序列。这表明病毒RNA的3'端存在异质性，这种现象在禽逆转录病毒中也有观察到。从3'端起的第37 - 45个核苷酸仅由A和T组成，类似于霍格内斯盒。这一发现可能对未整合和整合状态下前病毒DNA的转录产生生物学影响。我们发现的序列是AGUAAA，而不是在多聚腺苷酸化位点附近和之前的mRNA中通常存在的AAUAAA序列。
