Transcriptional Regulation Mechanism Research Of Equine Herpesvirus 1 Latency Associated Transcripts

Latency is an important characteristic of EHV-1, the restricted regions called latency associated transcripts (LATs) is transcribed in latency. In order to research the promoter activity, the transcription units and the six regulatory proteins regulation function about EHV-1 LATs. The potential promoter segment is truncated. The recombination luciferase reporter plasmids were constructed:pLAT(-63)-(1-7) and pLAT(64). These recombination plasmids were co-transfection with Renilla reporter plasmids in RK13 cell. Results show that pLAT(63)-1 initiate transcription of LAT(63) and pLAT(64) initiate transcription of LAT(64). EHV-1 two kinds of LATs transcription units was measured by 5’full Race kit and 3’full Race kit. And then, the six kinds of regulatory proteins recombination plasmids were respectively co-transfection with the recombination reporter plasmids in RK13 cell. Results show that IEP, EICP22, EICP27 and ETIF can up-regulation the activity of pL AT(63) or pLAT(64). And ETIF is the strongest up-regulation for pLAT(63), EICP22 is the strongest for pLAT(64). IR2P down-regulation this two promoter; EICPO is no effect on pLAT(63) as well as has little up-regulation about pLAT(64). EICP22 can cooperate with IEP up -regulation this two kinds of promoter.Co-IP essays shown that EICPO, EICP22 and EICP27 can respectively interacted with TBP.It turned out that EHV-1 exist two kinds of LATs, and there is any difference between LAT(63) and LAT(64) on regulation function of six kinds regulatory proteins. This is good foundation for explore the function on LATs and reactivation from latency.