STRUCTURAL AND FUNCTIONAL STUDIES OF MAMMALIAN ENDOGENOUS RETROVIRAL SEQUENCES

水貂白血病细胞灶形成基因的核苷酸序列分析 鼠白血病病毒（L-MCF 13 MuLV）和非致白血病（NL）MCF 111 A MuLV 确定了这两个IN基因在它们的51个序列中存在分歧， 而31部分相当保守。的生物活性 使用体外构建的免疫印迹技术研究了MCF 13和MCF 111 A IN基因。 重组MCF 13 DNA中含有MCF 111 A IN基因。重组 病毒和亲本病毒的致白血病潜力进行了比较 以及未整合的和整合的前病毒DNA的比率。结果 表明两个MuLV IN基因整合酶活性不同。 内源性MCF MuLV相关DNA的IN基因的核苷酸序列 (B34)确定了该基因全长1230 bp，可能编码 一种功能性蛋白质比较序列分析表明， 内源性IN基因序列同源性为82%，氨基酸同源性为86 AKV嗜亲MuLV IN。 原位杂交分析表明，人内源性4-1 逆转录病毒相关的RNA在人脑和大脑中均以高水平表达， 和肾脏组织，但只在少数细胞中。

Nucleotide sequence of the IN genes of leukemogenic mink cell focus-forming murine leukemia virus (L-MCF13 MuLV) and non-leukemogenic (NL) MCF111A MuLV was determined. The two IN genes were diverged in their 51 sequences, whereas the 31 portion was fairly conserved. The biological activity of MCF13 and MCF111A IN genes was studies using an in vitro constructed recombinant MCF13 DNA which contained MCF111A IN gene. The recombinant virus and parental viruses were compared in their leukemogenic potential and ratios of unintegrated and integrated proviral DNAs. The results indicated that the two MuLV IN genes were different in integrase activity. Nucleotide sequence of the IN gene of an endogenous MCF MuLV-related DNA (B34) was determined. The gene was 1230 bp and could potentially encode for a functional protein. Comparative sequence analysis indicated that the endogenous IN gene had 82% sequence homology and 86% amino acid homology with AKV ecotropic MuLV IN. In situ hybridization analysis indicated that human endogenous 4-1 retroviral-related RNAs were expressed at high levels in both human brain and kidney tissues, but only in a few cells.