RTC without viral RNA template RTC with extending second-strand DNA RNase H-mediated digestion of tRNA, 3'PPT and cPPT RNA primers Authored: Gopinathrao, G, D'Eustachio, P, 2006-05-18 20:10:22 EC Number: 3.1.26.4 Edited: Gopinathrao, G, D'Eustachio, P, 2006-05-18 20:10:22 Pubmed10723025 Pubmed1370087 Pubmed15183342 RNase H catalyzes the precise cleavage of the bonds linking the primer tRNA attached to the minus-strand DNA, the 3' PPT RNA primer to the plus-strand strong-stop DNA, and the cPPT primer to the stretch of plus-strand DNA whose synthesis it primed. In each case, precise cleavage near the RNA-DNA junction occurs (Pullen et al. 1992). HIV-1 RT is the only reverse transcriptase that cleaves the tRNA:DNA junction so as to leave a ribo A residue from the tRNA at the 5' end of the minus strand.<p>While a single RT heterodimer could in principle catalyze DNA synthesis and primer RNA:DNA bond cleavage, evidence from several in vitro systems suggests that separate RT heterodimers are likely to catalyze these two reactions (Rausch and Le Grice 2004). Reactome Database ID Release 43173769 Reactome, http://www.reactome.org ReactomeREACT_8999 Reviewed: Hughes, SH, 2006-10-30 22:00:51