Title:Proteasome Activator Blm10 Regulates Transcription Especially During Aging
Volume: 22
Issue: 4
Author(s): Yu-Shan Chen, Xia Han, Kui Lin*, Tian-Xia Jiang *Xiao-Bo Qiu *
Affiliation:
- College of Life Sciences, Beijing Normal University, 19 Xinjiekouwai Avenue, Beijing 100875,China
- Ministry of Education Key Laboratory of Cell Proliferation & Regulation Biology, Beijing 100875,China
- Ministry of Education Key Laboratory of Cell Proliferation & Regulation Biology, Beijing 100875,China
Keywords:
Proteasome activator, Blm10, PA200, histone degradation, transcription, aging.
Abstract:
Background: Histones are basic elements of the chromatin and are critical to controlling
chromatin structure and transcription. The proteasome activator PA200 promotes the acetylation-
dependent proteasomal degradation of the core histones during spermatogenesis, DNA repair,
transcription, and cellular aging and maintains the stability of histone marks.
Objective: The study aimed to explore whether the yeast ortholog of PA200, Blm10, promotes
degradation of the core histones during transcription and regulates transcription especially during
aging.
Methods: Protein degradation assays were performed to detect the role of Blm10 in histone degradation
during transcription. mRNA profiles were compared in WT and mutant BY4741 or
MDY510 yeast cells by RNA-sequencing.
Results: The core histones can be degraded by the Blm10-proteasome in the non-replicating yeast,
suggesting that Blm10 promotes the transcription-coupled degradation of the core histones. Blm10
preferentially regulates transcription in aged yeast, especially transcription of genes related to translation,
amino acid metabolism, and carbohydrate metabolism. Mutations of Blm10 at
F2125/N2126 in its putative acetyl-lysine binding region abolished the Blm10-mediated regulation
of gene expression.
Conclusion: Blm10 promotes degradation of the core histones during transcription and regulates
transcription, especially during cellular aging, further supporting the critical role of PA200 in maintaining
the stability of histone marks from the evolutionary view. These results should provide
meaningful insights into the mechanisms underlying aging and the related diseases.
