tailieunhanh - Báo cáo y học: "Immunostaining of modified histones defines high-level features of the human metaphase epigenome"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Wertheim cung cấp cho các bạn kiến thức về ngành y đề tài: Immunostaining of modified histones defines high-level features of the human metaphase epigenome. | Terrenoire et al. Genome Biology 2010 11 R110 http 2010 11 11 R110 Genome Biology RESEARCH Open Access Immunostaining of modified histones defines high-level features of the human metaphase epigenome PHii In Torronr ti m1 2t Ciz- .v- -J MfP n n2lH1 3t Ạ I I2 Icsỉll 1 D21 1I2 Dtmci2 Df tHcirl c 11 lir imA G irf In4 5 A M2 I Mm D IGwIor6 Edim leiieilUlie Fiona Mcnonald Joiin A HalSall raUla rage nUUelt S Illlligwouil A Malcolm R Taylor Val Davison2 Laura P O Neill1 Bryan M Turner1 Abstract Background Immunolabeling of metaphase chromosome spreads can map components of the Human epigenome at tHe single cell level. Previously tHere Has been no systematic attempt to explore tHe potential of tHis approacH for epigenomic mapping and tHereby to complement approacHes based on cHromatin immunoprecipitation CHIP and sequencing tecHnologies. Results By immunostaining and immunofluorescence microscopy we Have defined tHe distribution of selected Histone modifications across metapHase cHromosomes from normal Human lympHoblastoid cells and constructed immunostained karyotypes. Histone modifications H3K9ac H3K27ac and H3K4me3 are all located in the same set of sHarply defined immunofluorescent bands corresponding to 10- to 50-Mb genomic segments. Primary fibroblasts gave broadly tHe same banding pattern. Bands co-localize witH regions relatively ricH in genes and CpG islands. Staining intensity usually correlates witH gene CpG island content but occasional exceptions suggest tHat otHer factors sucH as transcription or SINE density also contribute. H3K27me3 a mark associated witH gene silencing defines a set of bands tHat only occasionally overlap witH gene-ricH regions. Comparison of metapHase bands witH Histone modification levels across tHe interpHase genome ENCODE CHIP-seq sHows a close correspondence for H3K4me3 and H3K27ac but major differences for H3K27me3. Conclusions At metapHase tHe Human genome is packaged as cHromatin in wHicH combinations of Histone .