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The role of heterodimeric AP-1 protein comprised of JunD and c-Fos proteins in hematopoiesis.

ABSTRACT: Activator protein-1 (AP-1) regulates a wide range of cellular processes including proliferation, differentiation, and apoptosis. As a transcription factor, AP-1 is commonly found as a heterodimer comprised of c-Jun and c-Fos proteins. However, other heterodimers may also be formed. The function of these dimers, specifically the heterodimeric AP-1 comprised of JunD and c-Fos (AP-1(JunD/c-Fos)), has not been elucidated. Here, we identified a function of AP-1(JunD/c-Fos) in Xenopus hematopoiesis. A gain-of-function study performed by overexpressing junD and c-fos and a loss-of-function study using morpholino junD demonstrate a critical role for AP-1(JunD/c-Fos) in hematopoiesis during Xenopus embryogenesis. Additionally, we confirmed that JunD of AP-1(JunD/c-Fos) is required for BMP-4-induced hematopoiesis. We also demonstrated that BMP-4 regulated JunD activity at the transcriptional regulation and post-translational modification levels. Collectively, our findings identify AP-1(JunD/c-Fos) as a novel hematopoietic transcription factor and the requirement of AP-1(JunD/c-Fos) in BMP-4-induced hematopoiesis during Xenopus hematopoiesis.

SUBMITTER: Lee SY

PROVIDER: S-EPMC3438963 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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The role of heterodimeric AP-1 protein comprised of JunD and c-Fos proteins in hematopoiesis.

Lee Sung-Young SY Yoon Jaeho J Lee Mee-Hyun MH Jung Sung Keun SK Kim Dong Joon DJ Bode Ann M AM Kim Jaebong J Dong Zigang Z

The Journal of biological chemistry 20120720 37

Activator protein-1 (AP-1) regulates a wide range of cellular processes including proliferation, differentiation, and apoptosis. As a transcription factor, AP-1 is commonly found as a heterodimer comprised of c-Jun and c-Fos proteins. However, other heterodimers may also be formed. The function of these dimers, specifically the heterodimeric AP-1 comprised of JunD and c-Fos (AP-1(JunD/c-Fos)), has not been elucidated. Here, we identified a function of AP-1(JunD/c-Fos) in Xenopus hematopoiesis. A ...[more]

PMID: 22822070

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Dataset Information

The role of heterodimeric AP-1 protein comprised of JunD and c-Fos proteins in hematopoiesis.

Publications

The role of heterodimeric AP-1 protein comprised of JunD and c-Fos proteins in hematopoiesis.

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