Michi Miura    Department   Kawasaki Medical School  Kawasaki Medical School, Department of Microbiology,    Position   Instructor
Article types	原著
Language	English
Peer review	Peer reviewed
Title	Epigenetic changes around the pX region and spontaneous HTLV-1 transcription are CTCF-independent.
Journal	Formal name：Wellcome open research Abbreviation：Wellcome Open Res ISSN code：2398502X/2398502X
Domestic / Foregin	Foregin
Volume, Issue, Page	3,pp.105
Author and coauthor	Miura Michi, Miyazato Paola, Satou Yorifumi, Tanaka Yuetsu, Bangham Charles R M
Authorship	Lead author
Publication date	2018/12
Summary	Background: The human retrovirus HTLV-1 inserts the viral complementary DNA of 9 kb into the host genome. Both plus- and minus-strands of the provirus are transcribed, respectively from the 5' and 3' long terminal repeats (LTR). Plus-strand expression is rapid and intense once activated, whereas the minus-strand is transcribed at a lower, more constant level. To identify how HTLV-1 transcription is regulated, we investigated the epigenetic modifications associated with the onset of spontaneous plus-strand expression and the potential impact of the host factor CTCF. Methods: Patient-derived peripheral blood mononuclear cells (PBMCs) and in vitro HTLV-1-infected T cell clones were examined. Cells were stained for the plus-strand-encoded viral protein Tax, and sorted into Tax + and Tax - populations. Chromatin immunoprecipitation and methylated DNA immunoprecipitation were performed to identify epigenetic modifications in the provirus. Bisulfite-treated DNA fragments from the HTLV-1 LTRs were sequenced. Single-molecule RNA-FISH was performed, targeting HTLV-1 transcripts, for the estimation of transcription kinetics. The CRISPR/Cas9 technique was applied to alter the CTCF-binding site in the provirus, to test the impact of CTCF on the epigenetic modifications. Results: Changes in the histone modifications H3K4me3, H3K9Ac and H3K27Ac were strongly correlated with plus-strand expression. DNA in the body of the provirus was largely methylated except for the pX and 3' LTR regions, regardless of Tax expression. The plus-strand promoter was hypomethylated when Tax was expressed. Removal of CTCF had no discernible impact on the viral transcription or epigenetic modifications. Conclusions: The histone modifications H3K4me3, H3K9Ac and H3K27Ac are highly dynamic in the HTLV-1 provirus: they show rapid change with the onset of Tax expression, and are reversible. The HTLV-1 provirus has an intrinsic pattern of epigenetic modifications that is independent of both the provirus inse
DOI	10.12688/wellcomeopenres.14741.2
PMID	30607369