[Frontiers in Bioscience 14, 1606-1618, January 1, 2009]

RNA-protein interactions in hepadnavirus reverse transcription

Jianming Hu, Li Lin

Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, PA 17033

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. RT-pgRNA interaction is critical for packaging of pgRNA into nucleocapsids
3.1. pgRNA determinants
3.1.1. ε RNA
3.1.2. Two regions are required for DHBV pgRNA packaging
3.1.3. The pgRNA cap
3.2. The RT protein determinants
4. RT-pgRNA interaction is required for viral DNA synthesis
4.1. Initiation of reverse transcription - protein priming
4.2. Minus strand DNA elongation
5. The core protein plays an active role in pgRNA packaging and DNA synthesis
6. Specific host factors are involved in nucleocapsid assembly and reverse transcription
6.1. Host chaperones are required for RT-ε interaction
6.2. Other host factors
7. Perspectives
8. Acknowledgments
9. References

1. ABSTRACT

The small DNA genome of hepadnaviruses is replicated by reverse transcription via an RNA intermediate. This RNA "pregenome" contains important signals that control critical steps of viral replication, including RNA packaging, initiation of reverse transcription, and elongation of minus strand DNA, through specific interactions with the viral reverse transcriptase, the capsid protein, and host factors. In particular, the interaction between the viral reverse transcriptase and RNA pregenome requires a host chaperone complex composed of the heat shock protein 90 and its cochaperones.