Abstract
Conservation of the vertebrate body plan has been attributed to the evolutionary stability of gene-regulatory networks (GRNs). We describe a regulatory circuit made up of Gata2, Fli1, and Scl/Tal1 and their enhancers, Gata2-3, Fli1+12, and Scl+19, that operates during specification of hematopoiesis in the mouse embryo. We show that the Fli1+12 enhancer, like the Gata2-3 and Scl+19 enhancers, targets hematopoietic stem cells (HSCs) and relies on a combination of Ets, Gata, and E-Box motifs. We show that the Gata2-3 enhancer also uses a similar cluster of motifs and that Gata2, Fli1, and Scl are expressed in embryonic day-11.5 dorsal aorta where HSCs originate and in fetal liver where they multiply. The three HSC enhancers in these tissues and in ES cell-derived hemangioblast equivalents are bound by each of these transcription factors (TFs) and form a fully connected triad that constitutes a previously undescribed example of both this network motif in mammalian development and a GRN kernel operating during the specification of a mammalian stem cell.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Animals
-
Basic Helix-Loop-Helix Transcription Factors / chemistry
-
Basic Helix-Loop-Helix Transcription Factors / genetics
-
Basic Helix-Loop-Helix Transcription Factors / metabolism*
-
Binding Sites
-
Blood Vessels / embryology
-
Blood Vessels / physiology
-
Embryo, Mammalian / physiology
-
Enhancer Elements, Genetic
-
GATA2 Transcription Factor / chemistry
-
GATA2 Transcription Factor / genetics
-
GATA2 Transcription Factor / metabolism*
-
Gene Expression Regulation
-
Hematopoiesis / physiology*
-
Hematopoietic Stem Cells / physiology*
-
Mice
-
Proto-Oncogene Protein c-fli-1 / chemistry
-
Proto-Oncogene Protein c-fli-1 / genetics
-
Proto-Oncogene Protein c-fli-1 / metabolism*
-
Proto-Oncogene Proteins / chemistry
-
Proto-Oncogene Proteins / genetics
-
Proto-Oncogene Proteins / metabolism*
-
T-Cell Acute Lymphocytic Leukemia Protein 1
Substances
-
Basic Helix-Loop-Helix Transcription Factors
-
Fli1 protein, mouse
-
GATA2 Transcription Factor
-
Gata2 protein, mouse
-
Proto-Oncogene Protein c-fli-1
-
Proto-Oncogene Proteins
-
T-Cell Acute Lymphocytic Leukemia Protein 1
-
Tal1 protein, mouse