CpG islands are important in the protection of adjacent housekeeping genes from de novo DNA methylation and for keeping them in a transcriptionally active state. However, little is known about their capacity to protect heterologous genes and assure position-independent transcription of adjacent transgenes or retroviral vectors. To tackle this question, we have used the mouse aprt CpG island to flank a Rous sarcoma virus (RSV)-derived reporter vector and followed the transcriptional activity of integrated vectors. RSV is an avian retrovirus which does not replicate in mammalian cells because of several blocks at all levels of the replication cycle. Here we show that our RSV-derived reporter proviruses linked to the mouse aprt gene CpG island remain undermethylated and keep their transcriptional activity after stable transfection into both avian and nonpermissive mammalian cells. This effect is most likely caused by the protection from de novo methylation provided by the CpG island and not by enhancement of the promoter strength. Our results are consistent with previous finding of CpG islands in proximity to active but not inactive proviruses and support further investigation of the protection of the gene transfer vectors from DNA methylation.

• MeSH
• adeninfosforibosyltransferasa genetika   MeSH
• buněčné linie virologie   MeSH
• CpG ostrůvky * MeSH
• defektní viry genetika   MeSH
• DNA virů chemie   genetika   MeSH
• DNA-(cytosin-5-)methyltransferasa metabolismus   MeSH
• experimentální sarkom genetika   virologie   MeSH
• fibroblasty virologie   MeSH
• genetická transkripce * MeSH
• genetické vektory genetika   fyziologie   MeSH
• integrace viru MeSH
• koncové repetice MeSH
• křečci praví MeSH
• křeček rodu Mesocricetus MeSH
• kuřecí embryo MeSH
• metylace DNA MeSH
• myši MeSH
• proviry genetika   MeSH
• regulace exprese virových genů * MeSH
• replikace viru MeSH
• reportérové geny MeSH
• umlčování genů * MeSH
• viry ptačího sarkomu genetika   fyziologie   MeSH
• zvířata MeSH
• Check Tag
• křečci praví MeSH
• kuřecí embryo MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• adeninfosforibosyltransferasa MeSH
• DNA virů MeSH
• DNA-(cytosin-5-)methyltransferasa MeSH