title: Induction of erythroid-specific genes by overexpression of GATA-2 in K562 cells.
abstract: GATA transcription factors have been shown to play important roles in hematopoiesis. GATA-2 is expressed in stem and progenitor cells, and has been speculated to control the proliferation and maintain the immaturity of these cells. To examine whether the function of GATA-2 is changeable according to the differentiation stage, we established GATA-2 overexpressing subclones of K562, which is a leukemic cell line committed to the erythroid lineage. Via an increase in the GATA-2 expression level, the expression levels of erythroid-specific genes including alpha-, beta-, and gamma-globin were increased compared to control cells, while the expression level of GATA-1 was unchanged. Expression of the transferrin receptor was also increased in GATA-2 overexpressing K562 cells when examined by flow cytometry. In addition, the heme content of GATA-2 overexpressing K562 cells was more than 2 times higher than control cells. Chromatin immunoprecipitation analysis showed that GATA-2 protein binding to the GATA element in alpha-globin LCR was increased in GATA-2 overexpressing K562 cells. These findings suggest that GATA-2 could induce erythroid-specific genes without competition with GATA-1 when expressed in erythroid-committed cells, and thus further suggest that temporal and spatial regulation may be important for displaying specific functions of GATA-2.
authors.affiliation: Department of Rheumatology and Hematology, Tohoku University Graduate School of Medicine, Sendai, Japan. harigae@mail.tains.tohoku.ac.jp
authors.forename: Hideo
authors.initials: H
authors.lastname: Harigae
authors.forename: Yoko
authors.initials: Y
authors.lastname: Okitsu
authors.forename: Hisayuki
authors.initials: H
authors.lastname: Yokoyama
authors.forename: Tohru
authors.initials: T
authors.lastname: Fujiwara
authors.forename: Mitsue
authors.initials: M
authors.lastname: Inomata
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Takahashi
authors.forename: Naoko
authors.initials: N
authors.lastname: Minegishi
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Kaku
authors.forename: Takeshi
authors.initials: T
authors.lastname: Sasaki
mesh_terms: D002454:Cell Differentiation / Q000502:physiology*; D002843:Chromatin / Q000235:genetics / Q000378:metabolism; D015672:Erythroid Precursor Cells / Q000378:metabolism*; D004920:Erythropoiesis / Q000235:genetics; D050989:GATA2 Transcription Factor / Q000096:biosynthesis* / Q000235:genetics; D015870:Gene Expression; D005786:Gene Expression Regulation / Q000235:genetics; D006801:Humans; D020014:K562 Cells
chemical_list: D002843:Chromatin; D050989:GATA2 Transcription Factor