In eukaryotes, kinetochore assembly takes place on the centromere. The histone H3 variant CENP-A is important for this process and for maintenance of centromere epigenetic identity. In addition, the centromeric alpha-satellite DNA contains a specific set of post-translational modifications and is transcribed at low levels. Removing the H3K4 dimethylation mark on kinetochore chromatin results in a decrease in transcription and prevents the loading of CENP-A, thereby disrupting kinetochores. But is it the chromatin environment or the level of transcription that is important for CENP-A recruitment? By using human artificial chromosome rich in alpha-satellite sequences, Bill Earnshaw and co-workers (p. 411) provide an answer to this question. They show that the C-terminal transactivation domains from the NF-κB p65 subunit and the herpes virus VP16 upregulate H3K9 acetylation to a similar level, and increase transcription ~10- and ~150-fold, respectively. The changes induced by p65 do not affect kinetochore structure or function. By contrast, the greater increase in transcriptional activity induced by VP16 is accompanied by a loss of pre-assembled CENP-A from the kinetochore as well as defective CENP-A loading. From these results, the authors conclude that transcriptional activity from centromeric chromatin has to be carefully balanced to maintain kinetochore integrity.
Transcription disrupts kinetochores
Transcription disrupts kinetochores. J Cell Sci 15 January 2012; 125 (2): e202. doi:
Download citation file:
Advertisement
Cited by
2021 JCS Prize winner announced
-JCSPrize.png?versionId=3749)
We are pleased to announce that the winner of the 2021 JCS Prize is Lee Dolat for his paper entitled ‘An endometrial organoid model of interactions between Chlamydia and epithelial and immune cells’.
Propose a new Workshop
-GSWorkshop.png?versionId=3749)
Our Workshops bring together leading experts and early-career researchers from a range of scientific backgrounds. Applications are now open to propose Workshops for 2024, one of which will be held in a Global South country.
Cell scientist to watch: Christian Münch
-CSTW.png?versionId=3749)
Journal of Cell Science interviewed Christian Münch, who established his independent research group in 2016 at Goethe University Frankfurt. His lab studies cellular stress responses to mitochondrial protein misfolding, infection and disease, as well as developing proteomics methods.
Essay series: Equity, diversity and inclusion in cell biology
-EssaySeries.png?versionId=3749)
The JCS Essay Series is an initiative to help showcase and provide a platform for voices in the field of cell biology. The first topic we covered was 'Equity, diversity and inclusion in cell biology', and the winning and runner up essays are now available to read.
FocalPlane Network launched
-FocalPlaneNetworkLaunch.png?versionId=3749)
We are excited to announce the launch of the FocalPlane Network, an international directory of microscopists. The idea behind the FocalPlane Network is to facilitate promotion and networking as well as assist those seeking conference speakers, committee members, reviewers or collaborators. We hope that it will help promote diversity in the community. Find out more and join the Network here.