Ribonuclease H of reverse transcriptase and cellular RNases H are related proteins, both structurally and enzymatically. However, they differ in several aspects. Experiments designed to determine the sequences and structures that contribute to the differences between the two types of RNases H have been a focus of some of our project. We have expressed the RNase H domains of HIV and MuLV as separate proteins and studied some of its properties related to binding to RNA-DNA hybrids. E. coli RNase HI is more than 1,000 times as active enzymatically as either of the RNases H derived from the mammalian retroviruses. E. coli RNase HI binds very rapidly to RNA-DNA hybrids as does the MuLV RNase H. Thus, the differences in specific activity between these two enzymes is due to a difference in catalytic activity. In contrast, an E. coli RNase H protein deleted for the region known to be responsible interacting with RNA-DNA substrates (making it similar to HIV RNase H) binds very poorly to its substrate. When we target E. coli RNase H to mammalian retroviruses and yeast retrotransposons, differences in enzymatic properties result in inhibition of viral multiplication for MuLV, TY-1 and possibly HIV. Thus, targeting of cellular RNase H to virus particles may be a useful method for containing retroviral infections.
| Nowotny, Marcin; Gaidamakov, Sergei A; Ghirlando, Rodolfo et al. (2007) Structure of human RNase H1 complexed with an RNA/DNA hybrid: insight into HIV reverse transcription. Mol Cell 28:264-76 |
| Budihas, Scott R; Gorshkova, Inna; Gaidamakov, Sergei et al. (2005) Selective inhibition of HIV-1 reverse transcriptase-associated ribonuclease H activity by hydroxylated tropolones. Nucleic Acids Res 33:1249-56 |
| Gaidamakov, Sergei A; Gorshkova, Inna I; Schuck, Peter et al. (2005) Eukaryotic RNases H1 act processively by interactions through the duplex RNA-binding domain. Nucleic Acids Res 33:2166-75 |
| Nowotny, Marcin; Gaidamakov, Sergei A; Crouch, Robert J et al. (2005) Crystal structures of RNase H bound to an RNA/DNA hybrid: substrate specificity and metal-dependent catalysis. Cell 121:1005-16 |
| Chan, King C; Budihas, Scott R; Le Grice, Stuart F J et al. (2004) A capillary electrophoretic assay for ribonuclease H activity. Anal Biochem 331:296-302 |
| Jeong, Ho-Sang; Backlund, Peter S; Chen, Hao-Chia et al. (2004) RNase H2 of Saccharomyces cerevisiae is a complex of three proteins. Nucleic Acids Res 32:407-14 |
| Broccoli, Sonia; Rallu, Fabien; Sanscartier, Patrick et al. (2004) Effects of RNA polymerase modifications on transcription-induced negative supercoiling and associated R-loop formation. Mol Microbiol 52:1769-79 |
| Backer, Marina V; Gaynutdinov, Timur I; Gorshkova, Inna I et al. (2003) Humanized docking system for assembly of targeting drug delivery complexes. J Control Release 89:499-511 |
| Pileur, Frederic; Andreola, Marie-Line; Dausse, Eric et al. (2003) Selective inhibitory DNA aptamers of the human RNase H1. Nucleic Acids Res 31:5776-88 |
| Cerritelli, Susana M; Frolova, Ella G; Feng, Chiguang et al. (2003) Failure to produce mitochondrial DNA results in embryonic lethality in Rnaseh1 null mice. Mol Cell 11:807-15 |
Showing the most recent 10 out of 18 publications
