Posted by: shrikantmantri | October 27, 2009

A novel strategy of transcription regulation by intra-genic nucleosome ordering [RESEARCH]

A novel strategy of transcription regulation by intra-genic nucleosome ordering [RESEARCH]

from GR-in-Advance
by Vaillant, C., Palmeira, L., Chevereau, G., Audit, B., d'Aubenton-Carafa, Y., Thermes, C., Arneodo, A.

Numerous studies of chromatin structure showed that nucleosome free regions (NFRs) located at 5' gene ends contribute to transcription initiation regulation. Here, we determine the role of intragenic chromatin structure on gene expression regulation. We show that, along S. cerevisiae genes, nucleosomes are highly organized following two types of architecture that depend only on the distance between the NFRs located at the 5' and 3' gene ends. In the first type, this distance constraints in vivo the positioning of n nucleosomes regularly organized in a "crystal-like" array. In the second type, this distance is such that the corresponding genes can accomodate either n or (n+1) nucleosomes thereby displaying two possible "crystal-like" arrays of n weakly-compacted or n+1 highly-compacted nucleosomes. This adaptability confers "bi-stable" properties to chromatin and is a key to its dynamics. Compared to "crystal-like" genes, "bi-stable" genes present higher transcriptional plasticity, higher sensitivity to chromatin regulators, higher H3 turnover rate and lower H2A.Z enrichment. The results strongly suggest that transcription elongation is facilitated by higher chromatin compaction. The data allow us to propose a new paradigm of transcriptional control mediated by the stability and the level of compaction of the intragenic chromatin architecture and open new ways for investigating eukaryotic gene expression regulation.

Thanks and Regards,
Shrikant Mantri

Memory Feeds Imagination,Imagination feeds IT….IT's Life

Posted via email from Sharing significant bytes —(Shrikant Mantri)

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Categories

%d bloggers like this: