title: Cell- and stage-specific chromatin structure across the Complement receptor 2 (CR2/CD21) promoter coincide with CBF1 and C/EBP-beta binding in B cells.
abstract: Stringent developmental transcription requires multiple transcription factor (TF) binding sites, cell-specific expression of signaling molecules, TFs and co-regulators and appropriate chromatin structure. During B-lymphopoiesis, human Complement receptor 2 (CR2/CD21) is detected on immature and mature B cells but not on B cell precursors and plasma cells. We examined cell- and stage-specific human CR2 gene regulation using cell lines modeling B-lymphopoiesis. Chromatin accessibility assays revealed a region between -409 and -262 with enhanced accessibility in mature B cells and pre-B cells, compared to either non-lymphoid or plasma cell-types, however, accessibility near the transcription start site (TSS) was elevated only in CR2-expressing B cells. A correlation between histone acetylation and CR2 expression was observed, while histone H3K4 dimethylation was enriched near the TSS in both CR2-expressing B cells and non-expressing pre-B cells. Candidate sites within the CR2 promoter were identified which could regulate chromatin, including a matrix attachment region associated with CDP, SATB1/BRIGHT and CEBP-beta sites as well as two CBF1 sites. ChIP assays verified that both CBF1 and C/EBP-beta bind the CR2 promoter in B cells raising the possibility that these factors facilitate or respond to alterations in chromatin structure to control the timing and/or level of CR2 transcription.
authors.affiliation: The University of Western Australia, Australia.
authors.forename: Mark N
authors.initials: MN
authors.lastname: Cruickshank
authors.forename: Emily
authors.initials: E
authors.lastname: Fenwick
authors.forename: Mahdad
authors.initials: M
authors.lastname: Karimi
authors.forename: Lawrence J
authors.initials: LJ
authors.lastname: Abraham
authors.forename: Daniela
authors.initials: D
authors.lastname: Ulgiati
mesh_terms: D000107:Acetylation; D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000378:metabolism*; D001665:Binding Sites / Q000235:genetics; D022782:CCAAT-Enhancer-Binding Protein-beta / Q000378:metabolism*; D002460:Cell Line; D045744:Cell Line, Tumor; D002843:Chromatin / Q000378:metabolism*; D047369:Chromatin Immunoprecipitation; D005434:Flow Cytometry; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006657:Histones / Q000378:metabolism; D006801:Humans; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein / Q000378:metabolism*; D019169:Jurkat Cells; D020014:K562 Cells; D051379:Mice; D011401:Promoter Regions, Genetic / Q000235:genetics*; D011485:Protein Binding; D017464:Receptors, Complement 3d / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D024363:Transcription Initiation Site; D020298:U937 Cells
chemical_list: D022782:CCAAT-Enhancer-Binding Protein-beta; D002843:Chromatin; D006657:Histones; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein; C497570:RBPJ protein, human; D017464:Receptors, Complement 3d