title: A subset of histone H2B genes produces polyadenylated mRNAs under a variety of cellular conditions.
abstract: Unlike other metazoan mRNAs, replication-dependent histone gene transcripts are not polyadenylated but instead have a conserved stem-loop structure at their 3' end. Our previous work has shown that under certain conditions replication-dependent histone genes can produce alternative transcripts that are polyadenylated at the 3' end and, in some cases, spliced. A number of microarray studies examining the expression of polyadenylated mRNAs identified changes in the levels of histone transcripts e.g. during differentiation and tumorigenesis. However, it remains unknown which histone genes produce polyadenylated transcripts and which conditions regulate this process. In the present study we examined the expression and polyadenylation of the human histone H2B gene complement in various cell lines. We demonstrate that H2B genes display a distinct expression pattern that is varies between different cell lines. Further we show that the fraction of polyadenylated HIST1H2BD and HIST1H2AC transcripts is increased during differentiation of human mesenchymal stem cells (hMSCs) and human fetal osteoblast (hFOB 1.19). Furthermore, we observed an increased fraction of polyadenylated transcripts produced from the histone genes in cells following ionizing radiation. Finally, we show that polyadenylated transcripts are transported to the cytoplasm and found on polyribosomes. Thus, we propose that the production of polyadenylated histone mRNAs from replication-dependent histone genes is a regulated process induced under specific cellular circumstances.
authors.affiliation: Department of Tumor Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Vijayalakshmi
authors.initials: V
authors.lastname: Kari
authors.forename: Oleksandra
authors.initials: O
authors.lastname: Karpiuk
authors.forename: Bettina
authors.initials: B
authors.lastname: Tieg
authors.forename: Malte
authors.initials: M
authors.lastname: Kriegs
authors.forename: Ekkehard
authors.initials: E
authors.lastname: Dikomey
authors.forename: Heike
authors.initials: H
authors.lastname: Krebber
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Begus-Nahrmann
authors.forename: Steven A
authors.initials: SA
authors.lastname: Johnsen
mesh_terms: D059447:Cell Cycle Checkpoints / Q000235:genetics; D002454:Cell Differentiation / Q000235:genetics; D045744:Cell Line, Tumor; D003593:Cytoplasm / Q000235:genetics; D004261:DNA Replication / Q000235:genetics; D015870:Gene Expression / Q000235:genetics; D045325:HCT116 Cells; D006657:Histones / Q000235:genetics*; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000502:physiology; D010006:Osteoblasts / Q000502:physiology; D011132:Polyribosomes / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics*; D014158:Transcription, Genetic / Q000235:genetics; D016159:Tumor Suppressor Protein p53 / Q000235:genetics; D015854:Up-Regulation / Q000235:genetics
chemical_list: D006657:Histones; D012333:RNA, Messenger; D016159:Tumor Suppressor Protein p53