title: Critical role of biklf in erythroid cell differentiation in zebrafish.
abstract: Hematopoietic cells arise from ventral mesoderm in different vertebrates, but the mechanisms through which various factors contribute to the hematopoietic processes, including erythrogenesis, remain incompletely understood. The Krüppel-like transcription factor Biklf is preferentially expressed in blood islands throughout zebrafish embryogenesis, marking the region of future erythropoiesis [1]. In this paper, we show that expression of biklf is significantly suppressed in the blood-less mutants vampire and m683 in which primitive hematopoiesis is impaired. Knockdown of biklf using morpholino-based antisense oligonucleotides (biklf-MO) led to a potent reduction in the number of circulating blood cells and deficiency in hemoglobin production. Consistently, we found that the expression of beta(e3)globin is strongly suppressed in biklf-MO-injected embryos, while gata1 expression is partly inhibited at the 10-somite stage. In addition, analysis of reporter constructs driven by the GATA1 and beta-globin promoters showed that Biklf can positively regulate both genes. These results indicate that Biklf is required for erythroid cell differentiation in zebrafish.
authors.affiliation: Laboratory of Molecular Genetics, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: A
authors.initials: A
authors.lastname: Kawahara
authors.forename: I B
authors.initials: IB
authors.lastname: Dawid
mesh_terms: D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins; D002454:Cell Differentiation; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D015672:Erythroid Precursor Cells / Q000166:cytology*; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; D005914:Globins / Q000235:genetics / Q000378:metabolism; D051741:Kruppel-Like Transcription Factors; D011518:Proto-Oncogene Proteins; D000073942:T-Cell Acute Lymphocytic Leukemia Protein 1; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015027:Zebrafish; D029961:Zebrafish Proteins; D016335:Zinc Fingers / Q000235:genetics / Q000502:physiology*
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; D005914:Globins; D051741:Kruppel-Like Transcription Factors; D011518:Proto-Oncogene Proteins; D000073942:T-Cell Acute Lymphocytic Leukemia Protein 1; D014157:Transcription Factors; D029961:Zebrafish Proteins; C080774:erythroid Kruppel-like factor; C494691:gata1a protein, zebrafish; C418487:klf4 protein, zebrafish; C489367:tal1 protein, zebrafish