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Proteasome Activator Blm10 Regulates Transcription Especially During Aging
Yu-Shan Chen1, Xia Han1, Kui Lin1
11Ministry of Education Key Laboratory of Cell Proliferation & Regulation Biology, Beijing 100875, China; 2College of Life Sciences, Beijing Normal University, 19 Xinjiekouwai Avenue, Beijing 100875, China.
Current Genomics
|March 11, 2022
Summary
The yeast Blm10 protein degrades core histones during transcription, regulating gene expression, particularly in aged cells. This finding supports the evolutionary role of proteasome activators in maintaining histone stability.
Area of Science:
- Molecular Biology
- Genetics
- Cellular Biology
Background:
- Histones are fundamental chromatin components regulating structure and transcription.
- The proteasome activator PA200 degrades core histones, maintaining histone mark stability across various cellular processes.
Purpose of the Study:
- To investigate if the yeast ortholog of PA200, Blm10, degrades core histones during transcription.
- To determine Blm10's role in regulating transcription, especially during yeast aging.
Main Methods:
- Protein degradation assays were employed to assess Blm10's function in histone degradation.
- RNA-sequencing compared mRNA profiles in wild-type and Blm10 mutant yeast strains.
Main Results:
- Blm10 facilitates transcription-coupled degradation of core histones in non-replicating yeast.
- Blm10 preferentially impacts transcription in aged yeast, notably affecting genes involved in metabolism and translation.
- Mutations in Blm10's putative acetyl-lysine binding site disrupted its gene expression regulatory function.
Conclusions:
- Blm10 promotes histone degradation during transcription and regulates gene expression, particularly in aging cells.
- This study highlights the evolutionary conservation of PA200's role in histone mark stability.
- Findings offer insights into aging mechanisms and age-related diseases.
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