Detection of DNA intermediates of the reverse transcription during the infection process of the human endogenous retrovirus-K (HML-2)

Abstract

Endogenous retroviruses form part of the genome of many vertebrates. In humans they account for approximately 8 % of the entire genetic information. Along evolution the proviral sequences have been mutated until nowadays there is no known HERV able to express infectious particles. However the youngest and probably therefore the less mutated family, HERV-K (HML-2), preserves proviruses able to produce functional proteins. Although it has been shown that not only the glycoproteins responsible for mediating entry have been mutated, but also integration of the viral genes in the host genome will not be properly accomplished. In order to determine potential inhibited stages of this process, HERV-K pseudotyped viral particles able to mediate penetration of the cell membrane were successfully produced and monitored during reverse transcription on their course towards integration. For this purpose several set of primers were designed, that bind specific to different stages along the reverse transcription process. Using these primers reverse transcribed DNA could be detected. Consequently, analysis of these characteristics steps could ideally help to detect at some point of significant less cDNA, which may permit to infer the phase where inhibition takes place.