title: Description and targeted deletion of 5' hypersensitive site 5 and 6 of the mouse beta-globin locus control region.
abstract: The most upstream hypersensitive site (HS) of the beta-globin locus control region (LCR) in humans (5' HS 5) and chickens (5' HS 4) can act as an insulating element in some gain of function assays and may demarcate a beta-globin domain. We have mapped the most upstream HSs of the mouse beta-globin LCR and sequenced this region. We find that mice have a region homologous to human 5' HS 5 that is associated with a minor HS. In addition we map a unique HS upstream of 5' HS 5 and refer to this novel site as mouse 5' HS 6. We have also generated mice containing a targeted deletion of the region containing 5' HS 5 and 6. We find that after excision of the selectable marker in vivo, deletion of 5' HS 5 and 6 has a minimal effect on transcription and does not prevent formation of the remaining LCR HSs. Taken together these findings suggest that the most upstream HSs of the mouse beta-globin LCR are not necessary for maintaining the beta-globin locus in an active configuration or to protect it from a surrounding repressive chromatin environment.
authors.affiliation: Fred Hutchinson Cancer Research Center, Seattle, WA, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Bender
authors.forename: A
authors.initials: A
authors.lastname: Reik
authors.forename: J
authors.initials: J
authors.lastname: Close
authors.forename: A
authors.initials: A
authors.lastname: Telling
authors.forename: E
authors.initials: E
authors.lastname: Epner
authors.forename: S
authors.initials: S
authors.lastname: Fiering
authors.forename: R
authors.initials: R
authors.lastname: Hardison
authors.forename: M
authors.initials: M
authors.lastname: Groudine
mesh_terms: D000818:Animals; D002645:Chickens; D005786:Gene Expression Regulation; D005914:Globins / Q000235:genetics*; D006801:Humans; D051379:Mice; D005810:Multigene Family; D017421:Sequence Analysis; D017384:Sequence Deletion; D014158:Transcription, Genetic
chemical_list: D005914:Globins