title: Conservation of DNA bend sites with identical superhelical twists among the human, mouse, bovine, rabbit and chicken beta-globin genes.
abstract: We reported previously that DNA bend sites appear in the human beta-globin locus at an average distance of 680 bp. The relative locations of the sites were conserved among the five active beta-like globin genes and one pseudogene. Here, we mapped the sites in the beta-like globin genes from various species and examined their conservation. The locations of the bend sites in the bovine, rabbit and chicken beta-globin genes mapped here showed marked conservation in their locations relative to the cap site and showed similar locations to the previously mapped sites in the human beta- and mouse betamaj-globin genes. Further analysis of the first bend sites from the cap site (B-1 sites) indicated that they contained tracts of adenines and thymines longer than or equal to two bases. This sequence feature contributed mostly to the curvature profiles revealed by gel assays and/or by computer-based TRIF analysis. TRIF analysis indicated that most of the B-1 sites showed right-handed superhelical twists accompanied by left handed twists. This was confirmed by the effect of ethidium bromide on the superhelical twists in the assays.
authors.affiliation: National Institute of Bioscience and Human-Technology, Tsukuba, Ibaraki, Japan.
authors.forename: C
authors.initials: C
authors.lastname: Wanapirak
authors.forename: Y
authors.initials: Y
authors.lastname: Onishi
authors.forename: Y
authors.initials: Y
authors.lastname: Wada-Kiyama
authors.forename: T
authors.initials: T
authors.lastname: Ohyama
authors.forename: R
authors.initials: R
authors.lastname: Kiyama
mesh_terms: D000225:Adenine / Q000737:chemistry; D000818:Animals; D002417:Cattle; D002645:Chickens; D017124:Conserved Sequence; D004247:DNA / Q000737:chemistry*; D004278:DNA, Superhelical / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D005914:Globins / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D051379:Mice; D009707:Nucleosomes / Q000737:chemistry; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011544:Pseudogenes; D011817:Rabbits; D012984:Software; D013941:Thymine / Q000737:chemistry
chemical_list: D004278:DNA, Superhelical; D009707:Nucleosomes; D005914:Globins; D004247:DNA; D000225:Adenine; D013941:Thymine