title: eena Promotes myeloid proliferation through stimulating ERK1/2 phosphorylation in zebrafish.
abstract: The EEN (extra eleven nineteen) gene is one of the fusion partners of mixed-lineage leukemia, located on chromosome 19p13. Here we cloned two een genes (designated as eena and eenb) in zebrafish, which are assigned to linkage groups 8 and 2, respectively. Whole-mount in situ hybridization assay showed that eena and eenb have overlapping but distinct expression patterns during embryogenesis. Ubiquitous or targeted overexpression of eena, but not eenb, into wild-type or transgenic embryos (green fluorescent protein-labeled myeloid progenitors) induced a significant proliferation and ectopic distribution of myeloid progenitors in the yolk sac. Using a morpholino antisense gene knockdown approach, we showed that the number of myeloid progenitors and their downstream mature myelomonocytic cells was significantly decreased in the eena- deficient embryos. Mechanistically, overexpression of eena selectively stimulated ERK phosphorylation and increased the level of transcription factor c-Fos in vitro and in vivo, whereas eena lacking the Src homology 3 domain completely abolished these effects. Furthermore, a MAPK/ERK kinase (MEK) inhibitor, PD98059, blocked the eena-induced cell proliferation and activation of ERK signaling. The results suggest that eena plays an important role in the development of the myeloid cell through activation of the ERK pathway and may provide a valuable reference for future studies of the role of EEN in leukemogenesis.
authors.affiliation: Laboratory of Development and Diseases and State Key Laboratory of Medical Genomics, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and Shanghai Jiao Tong University School of Medicine,Shanghai 200025, China.
authors.forename: Huang-Ying
authors.initials: HY
authors.lastname: Le
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Han
authors.initials: H
authors.lastname: Liu
authors.forename: Li-Heng
authors.initials: LH
authors.lastname: Ma
authors.forename: Yi
authors.initials: Y
authors.lastname: Jin
authors.forename: Qiu-Hua
authors.initials: QH
authors.lastname: Huang
authors.forename: Yi
authors.initials: Y
authors.lastname: Chen
authors.forename: Min
authors.initials: M
authors.lastname: Deng
authors.forename: Zhu
authors.initials: Z
authors.lastname: Chen
authors.forename: Sai-Juan
authors.initials: SJ
authors.lastname: Chen
authors.forename: Ting Xi
authors.initials: TX
authors.lastname: Liu
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D002467:Cell Nucleus / Q000378:metabolism; D049109:Cell Proliferation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005786:Gene Expression Regulation; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism / Q000502:physiology*; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism*; D008954:Models, Biological; D022423:Myeloid Cells / Q000166:cytology*; D041681:NIH 3T3 Cells; D010766:Phosphorylation; D015027:Zebrafish; D029961:Zebrafish Proteins / Q000378:metabolism* / Q000502:physiology
chemical_list: D004791:Enzyme Inhibitors; D047908:Intracellular Signaling Peptides and Proteins; D029961:Zebrafish Proteins; C530262:sh3gl1a protein, zebrafish; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3