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Chinese hamster ovary cells contain transcriptionally active full-length type C proviruses.

ABSTRACT: We have isolated a genomic locus from Chinese hamster ovary (CHO) cells that contains a full-length provirus. Nucleotide sequence analysis indicates that it is a defective member of the rodent type C retrovirus family with an env region that is similar to those of mouse amphotropic retrovirus and subgroup B feline leukemia virus. We were able to demonstrate that this provirus is a member of a closely related family of full-length proviruses in CHO cells and Chinese hamster liver. Hybridization probes generated from this genomic clone were used to characterize type C retrovirus RNA expression in CHO cells. Full-length genomic RNA and subgenomic envelope mRNA were detected in CHO cell lines but not in the human-derived 293 cell line. Interestingly, we discovered that the site of retrovirus integration lies within a G repeat sequence belonging to the short interspersed element family of retroposons.

SUBMITTER: Lie YS

PROVIDER: S-EPMC237246 | biostudies-other | 1994 Dec

REPOSITORIES: biostudies-other

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Chinese hamster ovary cells contain transcriptionally active full-length type C proviruses.

Lie Y S YS Penuel E M EM Low M A MA Nguyen T P TP Mangahas J O JO Anderson K P KP Petropoulos C J CJ

Journal of virology 19941201 12

We have isolated a genomic locus from Chinese hamster ovary (CHO) cells that contains a full-length provirus. Nucleotide sequence analysis indicates that it is a defective member of the rodent type C retrovirus family with an env region that is similar to those of mouse amphotropic retrovirus and subgroup B feline leukemia virus. We were able to demonstrate that this provirus is a member of a closely related family of full-length proviruses in CHO cells and Chinese hamster liver. Hybridization p ...[more]

PMID: 7966574

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