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Imaging Centrosomes in Fly Testes
Published on: September 20, 2013
Drosophila CENH3 is sufficient for centromere formation
María José Mendiburo1, Jan Padeken, Stefanie Fülöp
1Max Planck Institute of Immunobiology, Stübeweg 51, 79108 Freiburg, Germany.
Science (New York, N.Y.)
|November 5, 2011
Summary
Centromere histone variant CENH3 (CID) is sufficient to establish heritable centromere identity. Ectopic CID can assemble functional kinetochores, demonstrating its role as an epigenetic mark for centromere function.
Area of Science:
- Epigenetics
- Molecular Biology
- Genetics
Background:
- CENH3 (CID) is a centromere-specific histone H3 variant crucial for kinetochore assembly.
- Evidence for CENH3 sufficiency in determining centromere identity has been lacking.
Purpose of the Study:
- To investigate whether CENH3 (CID) is sufficient to establish centromere identity and function.
- To explore the epigenetic self-propagation of centromere marks.
Main Methods:
- Artificially targeted Drosophila CENH3 (CENP-A/CID) using a CID-GFP-LacI fusion protein.
- Targeted the fusion protein to stable lac operator (lacO) arrays integrated into DNA.
Main Results:
- Ectopic CID foci successfully assembled functional kinetochores.
- These foci directed the incorporation of new CID molecules, indicating self-propagation of the epigenetic mark.
- Extrachromosomal plasmids with ectopic CID were stably transmitted across cell generations, even after the removal of the initial CID-GFP-LacI anchor.
Conclusions:
- CENH3 (CID) is both necessary and sufficient to act as an epigenetic centromere mark.
- CID nucleates heritable centromere function, establishing centromere identity independently.
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