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Productive life cycle of adeno-associated virus serotype 2 in the complete absence of a conventional polyadenylation signal.

ABSTRACT: We showed that WT adeno-associated virus serotype 2 (AAV2) genome devoid of a conventional polyadenylation [poly(A)] signal underwent complete genome replication, encapsidation and progeny virion production in the presence of adenovirus. The infectivity of the progeny virion was also retained. Using recombinant AAV2 vectors devoid of a human growth hormone poly(A) signal, we also demonstrated that a subset of mRNA transcripts contained the inverted terminal repeat (ITR) sequence at the 3' end, which we designated ITR in RNA (ITRR). Furthermore, AAV replication (Rep) proteins were able to interact with the ITRR. Taken together, our studies suggest a new function of the AAV2 ITR as an RNA element to mediate transgene expression from poly(A)-deleted mRNA.

SUBMITTER: Wang L

PROVIDER: S-EPMC4635500 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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Productive life cycle of adeno-associated virus serotype 2 in the complete absence of a conventional polyadenylation signal.

Wang Lina L Yin Zifei Z Wang Yuan Y Lu Yuan Y Zhang Daniel D Srivastava Arun A Ling Changquan C Aslanidi George V GV Ling Chen C

The Journal of general virology 20150630 9

We showed that WT adeno-associated virus serotype 2 (AAV2) genome devoid of a conventional polyadenylation [poly(A)] signal underwent complete genome replication, encapsidation and progeny virion production in the presence of adenovirus. The infectivity of the progeny virion was also retained. Using recombinant AAV2 vectors devoid of a human growth hormone poly(A) signal, we also demonstrated that a subset of mRNA transcripts contained the inverted terminal repeat (ITR) sequence at the 3' end, w ...[more]

PMID: 26297494

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