title: Regulation of GATA-binding protein 2 levels via ubiquitin-dependent degradation by Fbw7: involvement of cyclin B-cyclin-dependent kinase 1-mediated phosphorylation of THR176 in GATA-binding protein 2.
abstract: A GATA family transcription factor, GATA-binding protein 2 (GATA2), participates in cell growth and differentiation of various cells, such as hematopoietic stem cells. Although its expression level is controlled by transcriptional induction and proteolytic degradation, the responsible E3 ligase has not been identified. Here, we demonstrate that F-box/WD repeat-containing protein 7 (Fbw7/Fbxw7), a component of Skp1, Cullin 1, F-box-containing complex (SCF)-type E3 ligase, is an E3 ligase for GATA2. GATA2 contains a cell division control protein 4 (Cdc4) phosphodegron (CPD), a consensus motif for ubiquitylation by Fbw7, which includes Thr(176). Ectopic expression of Fbw7 destabilized GATA2 and promoted its proteasomal degradation. Substitution of threonine 176 to alanine in GATA2 inhibited binding with Fbw7, and the ubiquitylation and degradation of GATA2 by Fbw7 was suppressed. The CPD kinase, which mediates the phosphorylation of Thr(176), was cyclin B-cyclin-dependent kinase 1 (CDK1). Moreover, depletion of endogenous Fbw7 stabilized endogenous GATA2 in K562 cells. Conditional Fbw7 depletion in mice increased GATA2 levels in hematopoietic stem cells and myeloid progenitors at the early stage. Increased GATA2 levels in Fbw7-conditional knock-out mice were correlated with a decrease in a c-Kit high expressing population of myeloid progenitor cells. Our results suggest that Fbw7 is a bona fide E3 ubiquitin ligase for GATA2 in vivo.
authors: From the Departments of Molecular Biology and Oral and Maxillofacial Surgery and.
authors: Tomomi
authors: T
authors: Nakajima
authors: From the Departments of Molecular Biology and.
authors: Kyoko
authors: K
authors: Kitagawa
authors: From the Departments of Molecular Biology and.
authors: Tatsuya
authors: T
authors: Ohhata
authors: From the Departments of Molecular Biology and.
authors: Satoshi
authors: S
authors: Sakai
authors: the Research Equipment Center, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka 431-3192, Japan.
authors: Chiharu
authors: C
authors: Uchida
authors: the Research Equipment Center, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka 431-3192, Japan.
authors: Kiyoshi
authors: K
authors: Shibata
authors: the Department of Biobank Life Science, Tohoku University School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8573, Japan, and.
authors: Naoko
authors: N
authors: Minegishi
authors: the Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors: Kanae
authors: K
authors: Yumimoto
authors: the Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors: Keiichi I
authors: KI
authors: Nakayama
authors: Oral and Maxillofacial Surgery and.
authors: Kazuma
authors: K
authors: Masumoto
authors: Oral and Maxillofacial Surgery and.
authors: Fuminori
authors: F
authors: Katou
authors: From the Departments of Molecular Biology and.
authors: Hiroyuki
authors: H
authors: Niida
authors: From the Departments of Molecular Biology and kitamasa@hama-med.ac.jp.
authors: Masatoshi
authors: M
authors: Kitagawa
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D016203:CDC2 Protein Kinase; D018797:Cell Cycle Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D002454:Cell Differentiation; D019926:Cyclin B / Q000235:genetics* / Q000378:metabolism; D018844:Cyclin-Dependent Kinases / Q000235:genetics* / Q000378:metabolism; D044783:F-Box Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D000073979:F-Box-WD Repeat-Containing Protein 7; D050989:GATA2 Transcription Factor / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation; D038362:Glycogen Synthase Kinase 3 / Q000235:genetics / Q000378:metabolism; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D020014:K562 Cells; D051379:Mice; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D009154:Mutation; D010766:Phosphorylation; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D011485:Protein Binding; D059748:Proteolysis; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D025801:Ubiquitin / Q000235:genetics / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D054875:Ubiquitination
chemical_list: D018797:Cell Cycle Proteins; D019926:Cyclin B; D044783:F-Box Proteins; D000073979:F-Box-WD Repeat-Containing Protein 7; C513273:FBXW7 protein, human; D050989:GATA2 Transcription Factor; C494711:GATA2 protein, human; D034741:RNA, Small Interfering; D025801:Ubiquitin; D044767:Ubiquitin-Protein Ligases; D016203:CDC2 Protein Kinase; C528899:CDK1 protein, human; D018844:Cyclin-Dependent Kinases; D038362:Glycogen Synthase Kinase 3; D046988:Proteasome Endopeptidase Complex
keywords: Cyclin-dependent Kinase (CDK); Fbw7; GATA Transcription Factor; Phosphorylation; Protein Degradation; Ubiquitin Ligase; Ubiquitylation (Ubiquitination)