1. It's Prime Time for Reverse Transcriptase
Henry L Levin 
Cell 
Volume 88, Issue 1, Pages 5-8 (January 1997)
DOI: /S (00)
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2. Figure 1
The Priming Mechanisms of Retrovirus and Retrovirus Related RTs
(Top) The RTs of retroviruses and many LTR-retrotransposons prime reverse transcription from specific tRNA species (twisted red line) that are annealed to the mRNA (yellow) of the element. The red arrow indicates the direction of reverse transcription. (Middle) Tf1 is a member of a new family of LTR-retrotransposons that prime reverse transcription from a cleaved fragment of its own mRNA. The red tip of the mRNA (yellow) is the primer that is generated by the cleavage indicated by the scissors. The red arrow indicates the direction of reverse transcription that begins at the red primer and extends towards the 5' end of the mRNA. (Bottom) Hepatitis B viruses prime reverse transcription by forming a covalent bond to a tyrosine within the RT itself. The RT is depicted as a red burst and the red arrow indicates the direction of reverse transcription. The yellow line is the mRNA that contains the ε structures at each end.
Cell  , 5-8DOI: ( /S (00) )
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3. Figure 2 Priming Mechanisms of Enzymes Related to the Bacterial RTs
(Top) LINE-like elements and group II introns prime reverse transcription from a cleavage (single or double stranded) in the target DNA (straight yellow line). The primer is the red tip of the straight yellow line. The yellow wavy line represents the mRNA that serves as the template of reverse transcription (red arrow). (Middle) The Mauriceville plasmid encodes an RT (red burst) that does not require a primer. A tRNA-like structure at the 3' end of the mRNA (yellow wavey line) is essential for reverse transcription (red arrow). (Bottom) The RTs encoded by the bacterial retrons prime reverse transcription from an internal 2'OH. The yellow wavy line represents the mRNA and the red arrow shows the direction of reverse transcription that initiates from the 2'OH shown in black.
Cell  , 5-8DOI: ( /S (00) )
Copyright © 1997 Cell Press Terms and Conditions