RT Journal
A1 Jung, Inkyung
A1 Kim, Seung-Kyoon
A1 Kim, Mirang
A1 Han, Yong-Mahn
A1 Kim, Yong Sung
A1 Kim, Dongsup
A1 Lee, Daeyoup
T1 H2B monoubiquitylation is a 5′-enriched active transcription mark and correlates with exon–intron structure in human cells
JF Genome Research 
JO Genome Research 
YR 2012 
FD June 01 
VO 22 
IS 6 
SP 1026 
OP 1035 
DO 10.1101/gr.120634.111 
UL http://genome.cshlp.org/content/22/6/1026.abstract 
AB H2B monoubiquitylation (H2Bub1), which is required for multiple methylations of both H3K4 and H3K79, has been implicated in gene expression in numerous organisms ranging from yeast to human. However, the molecular crosstalk between H2Bub1 and other modifications, especially the methylations of H3K4 and H3K79, remains unclear in vertebrates. To better understand the functional role of H2Bub1, we measured genome-wide histone modification patterns in human cells. Our results suggest that H2Bub1 has dual roles, one that is H3 methylation dependent, and another that is H3 methylation independent. First, H2Bub1 is a 5′-enriched active transcription mark and co-occupies with H3K79 methylations in actively transcribed regions. Second, this study shows for the first time that H2Bub1 plays a histone H3 methylations-independent role in chromatin architecture. Furthermore, the results of this work indicate that H2Bub1 is largely positioned at the exon–intron boundaries of highly expressed exons, and it demonstrates increased occupancy in skipped exons compared with flanking exons in the human and mouse genomes. Our findings collectively suggest that a potentiating mechanism links H2Bub1 to both H3K79 methylations in actively transcribed regions and the exon–intron structure of highly expressed exons via the regulation of nucleosome dynamics during transcription elongation.