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Isolation of Primary Mouse Hepatocytes for Nascent Protein Synthesis Analysis by Non-radioactive L-azidohomoalanine Labeling Method
Published on: October 23, 2018
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A protein synthesis brake for hematopoietic stem cell maintenance
1Department of Biochemistry, School of Medicine, Southern University of Science and Technology, Shenzhen, Guangdong 518000, China.
Genes & Development
|October 7, 2022
Summary
The Polycomb protein Bmi1 regulates hematopoietic stem cell (HSC) maintenance by controlling ribosome biogenesis and protein synthesis. Bmi1 deficiency impairs HSC function through increased protein synthesis and proteostatic stress.
Area of Science:
- Molecular Biology
- Hematopoiesis
- Stem Cell Biology
Background:
- Bmi1 is crucial for normal and leukemic hematopoiesis.
- The specific target genes of Bmi1 in hematopoietic stem cells (HSCs) remain incompletely understood.
Purpose of the Study:
- To investigate the novel role of Bmi1 in regulating ribosome biogenesis and protein synthesis in HSCs.
- To elucidate the molecular mechanisms by which Bmi1 controls HSC maintenance.
Main Methods:
- Analysis of Bmi1-deficient HSCs.
- Gene expression profiling to identify upregulated genes, including ARX and ribosome biogenesis genes.
- Assessment of transplantability and hematopoietic defects.
- Investigation of the impact of ARX or p16/p19 depletion on Bmi1 loss-induced defects.
- Measurement of protein synthesis rates and proteostatic stress.
Main Results:
- Bmi1-deficient HSCs showed reduced transplantability.
- Upregulation of ARX and ribosome biogenesis genes was observed in Bmi1-deficient HSCs.
- Depletion of ARX or its targets (p16/p19) only partially rescued Bmi1 loss-induced hematopoietic defects.
- Bmi1-deficient HSCs exhibited increased protein synthesis rates and proteostatic stress.
Conclusions:
- Bmi1 plays a novel role in regulating ribosome biogenesis and protein synthesis, which is critical for HSC maintenance.
- Dysregulation of protein synthesis and proteostasis contributes to hematopoietic defects observed in Bmi1-deficient HSCs.
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