title: Zygotic nucleosome assembly protein-like 1 has a specific, non-cell autonomous role in hematopoiesis.
abstract: Nucleosome assembly proteins (NAPs) bind core histones, facilitate chromatin remodeling, and can act as transcriptional coactivators. We previously described the isolation of a Xenopus NAP1-like (xNAP1L) cDNA, which encodes a member of this protein family. Its zygotic expression is restricted to neural cells, the outer cells of the ventral blood island (VBIs), and the ectoderm overlying the blood precursors. Here, we report that depletion of zygotic xNAP1L in embryos produces no obvious morphologic phenotype, but ablates alpha-globin mRNA expression in the VBIs. Transcript levels of the hematopoietic precursor genes SCL and Xaml (Runx-1) are also reduced in the VBIs. SCL expression can be rescued by injection of xNAP1L mRNA into the ectoderm, showing that the effect of xNAP1L can be non-cell autonomous. Fli1 and Hex, genes expressed in hemangioblasts but subsequently endothelial markers, were unaffected, suggesting that xNAP1L is required for the hematopoietic lineage specifically. Our data are consistent with a requirement for xNAP1L upstream of SCL, and injection of SCL mRNA into xNAP1L-depleted embryos rescues alpha-globin expression. Thus, xNAP1L, which belongs to a family of proteins previously believed to have general roles, has a specific function in hematopoiesis.
authors.affiliation: School of Biological Sciences, Institute of Biomedical and Biomolecular Science, University of Portsmouth, Portsmouth PO1 2DT, United Kingdom.
authors.forename: Anita
authors.initials: A
authors.lastname: Abu-Daya
authors.forename: Wendy M
authors.initials: WM
authors.lastname: Steer
authors.forename: Alexandra F
authors.initials: AF
authors.lastname: Trollope
authors.forename: Christine E
authors.initials: CE
authors.lastname: Friedeberg
authors.forename: Roger K
authors.initials: RK
authors.lastname: Patient
authors.forename: Alan W
authors.initials: AW
authors.lastname: Thorne
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Guille
mesh_terms: D000818:Animals; D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D005914:Globins / Q000235:genetics; D006410:Hematopoiesis / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D066298:In Vitro Techniques; D009687:Nuclear Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D056490:Nucleosome Assembly Protein 1; D020319:Oligodeoxyribonucleotides, Antisense / Q000235:genetics / Q000494:pharmacology; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011817:Rabbits; D014981:Xenopus / Q000196:embryology / Q000235:genetics / Q000502:physiology; D029867:Xenopus Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology; D015053:Zygote / Q000502:physiology*
chemical_list: D018797:Cell Cycle Proteins; D009687:Nuclear Proteins; D056490:Nucleosome Assembly Protein 1; D020319:Oligodeoxyribonucleotides, Antisense; D012333:RNA, Messenger; D029867:Xenopus Proteins; D005914:Globins