A novel zebrafish jak2a(V581F) model shared features of human JAK2(V617F) polycythemia vera

• Published in: Experimental hematology 2009-12, Vol.37 (12), p.1379
• Main Authors: Ma, Alvin C H, Fan, August, Ward, Alister C, Liongue, Clifford, Lewis, Rowena S, Cheng, Suk H, Chan, P K, Yip, Sze-Fai, Liang, Raymond, Leung, Anskar Y H
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Amino Acid Substitution; Animals; Base Sequence; Blotting, Western; Disease Models, Animal; Embryo, Nonmammalian - enzymology; Embryo, Nonmammalian - metabolism; Erythropoiesis - genetics; Erythropoietin - genetics; Erythropoietin - metabolism; Gene Expression Regulation, Developmental; Humans; Janus Kinase 2 - antagonists & inhibitors; Janus Kinase 2 - genetics; Janus Kinase 2 - metabolism; Molecular Sequence Data; Mutagenesis, Site-Directed; Mutation; Polycythemia Vera - enzymology; Polycythemia Vera - genetics; Polycythemia Vera - pathology; Protein-Tyrosine Kinases - antagonists & inhibitors; Protein-Tyrosine Kinases - genetics; Protein-Tyrosine Kinases - metabolism; Pyrimidines - pharmacology; Reverse Transcriptase Polymerase Chain Reaction; Sequence Homology, Amino Acid; STAT5 Transcription Factor - genetics; STAT5 Transcription Factor - metabolism; Sulfonamides - pharmacology; Zebrafish - embryology; Zebrafish - genetics; Zebrafish - metabolism; Zebrafish Proteins - antagonists & inhibitors; Zebrafish Proteins - genetics; Zebrafish Proteins - metabolism
• ISSN: 1873-2399
• DOI: 10.1016/j.exphem.2009.08.008

The Janus kinase 2 (JAK2) is important for embryonic primitive hematopoiesis. A gain-of-function JAK2 (JAK2(V617F)) mutation in human is pathogenetically linked to polycythemia vera (PV). In this study, we generated a zebrafish ortholog of human JAK2(V617F) (referred herewith jak2a(V581F)) by site-directed mutagenesis and examined its relevance as a model of human PV. Zebrafish embryos at one-cell stage were injected with jak2a(V581F) mRNA (200pg/embryo). In some experiments, the embryos were treated with a specific JAK2 inhibitor, TG101209. The effects of jak2a stimulation on hematopoiesis, jak/stat signaling, and erythropoietin signaling were evaluated at 18-somites. Injection with jak2a(V581F) mRNA significantly increased erythropoiesis, as enumerated by flow cytometry based on gfp(+) population in dissociated Tg(gata1:gfp) embryos. The response was reduced by stat5.1 morpholino coinjection (control: 4.37% +/- 0.08%; jak2a(V581F) injected: 5.71% +/- 0.07%, coinjecting jak2a(V581F) mRNA and stat5.1 morpholino: 4.66% +/- 0.13%; p