title: The chAB4 and NF1-related long-range multisequence DNA families are contiguous in the centromeric heterochromatin of several human chromosomes.
abstract: We have investigated the large-scale organization of the human chAB4-related long-range multisequence family, a low copy-number repetitive DNA located in the pericentromeric heterochromatin of several human chromosomes. Analysis of genomic clones revealed large-scale ( approximately 100 kb or more) sequence conservation in the region flanking the prototype chAB4 element. We demonstrated that this low copy-number family is connected to another long-range repeat, the NF1-related (PsiNF1) multisequence. The two DNA types are joined by an approximately 2 kb-long tandem repeat of a 48-bp satellite. Although the chAB4- and NF1-like sequences were known to have essentially the same chromosomal localization, their close association is reported here for the first time. It indicates that they are not two independent long-range DNA families, but are parts of a single element spanning approximately 200 kb or more. This view is consistent both with their similar chromosomal localizations and the high levels of sequence conservation among copies found on different chromosomes. We suggest that the master copy of the linked chAB4-PsiNF1 DNA segment appeared first on the ancestor of human chromosome 17.
authors.affiliation: Institute of Genetics, Biological Research Center of the Hungarian Academy of Sciences, Szeged, Temesvári krt. 62, H-6701 Szeged, P.O.B. 521, Hungary. cserpani@nucleus.szbk.u-szeged.hu
authors.forename: Imre
authors.initials: I
authors.lastname: Cserpán
authors.forename: Róbert
authors.initials: R
authors.lastname: Katona
authors.forename: Tünde
authors.initials: T
authors.lastname: Praznovszky
authors.forename: Edit
authors.initials: E
authors.lastname: Novák
authors.forename: Márta
authors.initials: M
authors.lastname: Rózsavölgyi
authors.forename: Erika
authors.initials: E
authors.lastname: Csonka
authors.forename: Mónika
authors.initials: M
authors.lastname: Mórocz
authors.forename: Katalin
authors.initials: K
authors.lastname: Fodor
authors.forename: Gyula
authors.initials: G
authors.lastname: Hadlaczky
mesh_terms: D002503:Centromere / Q000235:genetics*; D002874:Chromosome Mapping; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics*; D004247:DNA / Q000737:chemistry / Q000235:genetics; D015894:Genome, Human; D006570:Heterochromatin / Q000235:genetics*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008969:Molecular Sequence Data; D025542:Neurofibromin 1 / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics*; D017422:Sequence Analysis, DNA; D016324:Sequence Tagged Sites
chemical_list: D006570:Heterochromatin; D025542:Neurofibromin 1; D004247:DNA