Related Experiment Video
Updated: Jun 4, 2026
05:35
Immunofluorescence Analysis of Endogenous and Exogenous Centromere-kinetochore Proteins
Published on: March 3, 2016
Dbp7 interacts with RNA exosome component Dis3 to mediate CENP-A loading to centromeres
Jinxin Gao1, Fengying Gao1, Qianhua Dong1
1Department of Biology, New York University, 24 Waverly Place, 6th Floor, New York, NY, 10003, USA.
Genome Biology
|June 3, 2026
Summary
A new mechanism for centromere assembly is uncovered. The RNA helicase Dbp7 and exosome subunit Dis3 bind centromeric transcripts, recruiting CENP-A via Sim3 to ensure proper chromosome segregation.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Centromeres are essential for chromosome segregation during cell division.
- Centromeres are epigenetically marked by CENP-A and transcribed into non-coding RNAs.
- The role of centromeric RNAs in CENP-A loading and R-loop formation is unclear.
Purpose of the Study:
- To investigate the role of centromeric RNAs in CENP-A loading.
- To understand mechanisms safeguarding centromeres from R-loop defects.
- To identify regulators of CENP-A loading.
Main Methods:
- Visual genetic screen in fission yeast.
- Domain-deletion analysis of Dbp7.
- Analysis of Dbp7-Dis3 interaction.
Main Results:
- Dbp7, an RNA helicase, prevents R-loop accumulation and is critical for CENP-A loading.
- Deletion of Dbp7 causes CENP-A mislocalization, chromosome segregation defects, and impaired silencing.
- Dbp7 interacts with Dis3, promoting CENP-A loading via Sim3.
Conclusions:
- Dbp7 and Dis3 bind centromeric transcripts to recruit CENP-A via Sim3.
- This reveals a novel CENP-A loading mechanism.
- Provides mechanistic insight into R-loop resolution at centromeres.
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