title: Transgenic analysis of the stem cell leukemia +19 stem cell enhancer in adult and embryonic hematopoietic and endothelial cells.
abstract: Appropriate transcriptional regulation is critical for the biological functions of many key regulatory genes, including the stem cell leukemia (SCL) gene. As part of a systematic dissection of SCL transcriptional regulation, we have previously identified a 5,245-bp SCL +18/19 enhancer that targeted embryonic endothelium together with embryonic and adult hematopoietic progenitors and stem cells (HSCs). This enhancer is proving to be a powerful tool for manipulating hematopoietic progenitors and stem cells, but the design and interpretation of such transgenic studies require a detailed understanding of enhancer activity in vivo. In this study, we demonstrate that the +18/19 enhancer is active in mast cells, megakaryocytes, and adult endothelium. A 644-bp +19 core enhancer exhibited similar temporal and spatial activity to the 5,245-bp +18/19 fragment both during development and in adult mice. Unlike the +18/19 enhancer, the +19 core enhancer was only active in adult mice when linked to the eukaryotic reporter gene human placental alkaline phosphatase. Activity of a single core enhancer in HSCs, endothelium, mast cells, and megakaryocytes suggests possible overlaps in their respective transcriptional programs. Moreover, activity in a proportion of thymocytes and other SCL-negative cell types suggests the existence of a silencer elsewhere in the SCL locus.
authors.affiliation: Department of Hematology, Cambridge Institute for Medical Research, Cambridge University, Hills Road, Cambridge CB2 2XY, UK.
authors.forename: Lev
authors.initials: L
authors.lastname: Silberstein
authors.forename: María-José
authors.initials: MJ
authors.lastname: Sánchez
authors.forename: Merav
authors.initials: M
authors.lastname: Socolovsky
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Gary
authors.initials: G
authors.lastname: Hoffman
authors.forename: Sarah
authors.initials: S
authors.lastname: Kinston
authors.forename: Sandie
authors.initials: S
authors.lastname: Piltz
authors.forename: Mark
authors.initials: M
authors.lastname: Bowen
authors.forename: Laure
authors.initials: L
authors.lastname: Gambardella
authors.forename: Anthony R
authors.initials: AR
authors.lastname: Green
authors.forename: Berthold
authors.initials: B
authors.lastname: Göttgens
mesh_terms: D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics*; D001854:Bone Marrow Cells / Q000166:cytology; D019070:Cell Lineage; D042783:Endothelial Cells / Q000166:cytology / Q000201:enzymology; D004742:Enhancer Elements, Genetic / Q000235:genetics*; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D008297:Male; D008407:Mast Cells / Q000166:cytology / Q000201:enzymology; D008533:Megakaryocytes / Q000166:cytology / Q000201:enzymology; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008822:Mice, Transgenic; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D000073942:T-Cell Acute Lymphocytic Leukemia Protein 1; D001616:beta-Galactosidase / Q000096:biosynthesis / Q000097:blood / Q000235:genetics
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D011518:Proto-Oncogene Proteins; D000073942:T-Cell Acute Lymphocytic Leukemia Protein 1; D001616:beta-Galactosidase; C489366:Tal1 protein, mouse