A silenced Plasmodium falciparum var promoter can be activated in vivo through spontaneous deletion of a silencing element in the intron.
نویسندگان
چکیده
Introns of Plasmodium falciparum var genes act as transcriptional silencing elements that help control antigenic variations. In transfected episomes, intron silencing of a drug-selectable marker under var promoter control is reversed by the spontaneous deletion of key intron regions. The resulting promoter activation does not affect the transcription of chromosomal var genes.
منابع مشابه
Plasmodium falciparum var gene silencing is determined by cis DNA elements that form stable and heritable interactions.
Antigenic variation in the human malaria parasite Plasmodium falciparum depends on the transcriptional regulation of the var gene family. In each individual parasite, mRNA is expressed exclusively from 1 var gene out of ∼60, while the rest of the genes are transcriptionally silenced. Both modifications to chromatin structure and DNA regulatory elements associated with each var gene have been im...
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ورودعنوان ژورنال:
- Eukaryotic cell
دوره 4 2 شماره
صفحات -
تاریخ انتشار 2005