title: Large-scale identification of novel potential disease loci in mouse leukemia applying an improved strategy for cloning common virus integration sites.
abstract: The identification of common virus integration sites (cVIS) in retrovirally induced tumors in mice provides a powerful strategy to isolate novel transforming genes. Applying virus LTR-specific inverse-PCR and RT-PCR combined with automated sequencing on CasBr-M Murine Leukemia Virus (MuLV) induced myeloid leukemias, 126 virus integration sites were cloned. Using locus- and LTR-specific primers, a nested-PCR/Southern-blotting procedure was developed on genomic DNA from a large panel of MuLV-induced leukemias, to analyse whether a particular virus insertion represented a cVIS. In fact 39 out of 41 integrations analysed this way appeared to represent a common virus integration. We recognized six previously cloned cVISs, i.e. Evi1, Hoxa7, c-Myb, Cb2/Evi11, Evi12, and His1 and 33 novel common insertions, designated Cas-Br Virus Integration Site (Casvis). Among this group we found integrations in or near genes encoding nuclear proteins, e.g. Dnmt-2, Nm23-M2, Ctbp1 or Erg, within receptor genes, e.g. Cb2 or mrc1, novel putative signaling or transporter genes, the ringfinger-protein gene Mid1 and a panel of genes encoding novel proteins with unknown function. The finding that 39 out of 41 integrations analysed represented a cVIS, suggests that the majority of the other virus insertions that were not yet analysed by the PCR/Southern-blotting method are located in a cVIS as well and may therefore also harbor novel disease genes.
authors.affiliation: The Institute of Hematology, Erasmus University Rotterdam, Dr. Molewaterplein 50, 3015GE Rotterdam, The Netherlands.
authors.forename: Marieke
authors.initials: M
authors.lastname: Joosten
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Vankan-Berkhoudt
authors.forename: Marjolein
authors.initials: M
authors.lastname: Tas
authors.forename: Monja
authors.initials: M
authors.lastname: Lunghi
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Jenniskens
authors.forename: Evan
authors.initials: E
authors.lastname: Parganas
authors.forename: Peter J M
authors.initials: PJ
authors.lastname: Valk
authors.forename: Bob
authors.initials: B
authors.lastname: Löwenberg
authors.forename: Eric
authors.initials: E
authors.lastname: van den Akker
authors.forename: Ruud
authors.initials: R
authors.lastname: Delwel
mesh_terms: D000818:Animals; D015139:Blotting, Southern; D003001:Cloning, Molecular; D009052:Leukemia Virus, Murine; D007951:Leukemia, Myeloid / Q000235:genetics*; D051379:Mice; D016254:Mutagenesis, Insertional; D016133:Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D020079:Terminal Repeat Sequences; D014407:Tumor Cells, Cultured; D016662:Virus Integration