MoBio Generation of Retroviral Genomic RNA Chapter 4

Replication of RNA retroviruses requires generation of retroviral genomic RNA from the integrated DNA. This involves the regular DNA to RNA transcription. The retroviral DNA contains two long terminal repeats (LTR), but only the upstream LTR directs transcription. Another LTR directs the cleavage of the primary transcript to add a poly-A tail.

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Figure 4-J-2. The LTR of HIV. It contains the recognition sites of several transcription factors in human cells. Transcription starts from the left end of the R region.

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Figure 4-J-3. Generation of retroviral genomic RNA. The primary transcript includes the right LTR which can direct the cleavage at the last nucleotide of the R region to add the poly-A tail.