Nonintegrating Foamy Virus Vectors
Nonintegrating Foamy Virus Vectors
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DOI：
10.1128/jvi.00394-10
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发表时间：
2010-09-15
影响因子：
5.4
通讯作者：
Russell, David W.
中科院分区：
文献类型：
--
作者：
Deyle, David R.;Li, Yi;Russell, David W.
泡沫病毒（FVs）或泡沫病毒是整合逆转录病毒的载体。在这里，我们产生非整合泡沫病毒（NIFV）载体，通过引入点突变到高度保守的DD 35 E催化核心基序的泡沫病毒整合酶序列。NIFV载体产生高滴度原液，转导分裂细胞，并且不整合。用NIFV载体感染的细胞含有附加型载体基因组，其由线性、1-长末端重复（1-LTR）和2-LTR环状DNA组成。这些游离体表达转基因，是稳定的，并在分裂细胞群中逐渐稀释。1-在感染前，在所有载体储液中均发现LTR环，但未发现2-LTR环。NIFV载体的残留整合发生频率比整合酶活性FV载体低4个对数。从NIFV载体表达的Cre重组酶介导了整合的、floxed FV载体和基因靶向的neo表达盒的切除，证明了这些附加型载体的实用性。NIFV载体的广泛宿主范围和大包装容量应使其可用于需要瞬时基因表达的各种应用。
Foamy viruses (FVs), or spumaviruses, are integrating retroviruses that have been developed as vectors. Here we generated nonintegrating foamy virus (NIFV) vectors by introducing point mutations into the highly conserved DD35E catalytic core motif of the foamy virus integrase sequence. NIFV vectors produced high-titer stocks, transduced dividing cells, and did not integrate. Cells infected with NIFV vectors contained episomal vector genomes that consisted of linear, 1-long-terminal-repeat (1-LTR), and 2-LTR circular DNAs. These episomes expressed transgenes, were stable, and became progressively diluted in the dividing cell population. 1-LTR circles but not 2-LTR circles were found in all vector stocks prior to infection. Residual integration of NIFV vectors occurred at a frequency 4 logs lower than that of integrase-proficient FV vectors. Cre recombinase expressed from a NIFV vector mediated excision of both an integrated, floxed FV vector and a gene-targeted neo expression cassette, demonstrating the utility of these episomal vectors. The broad host range and large packaging capacity of NIFV vectors should make them useful for a variety of applications requiring transient gene expression.