Monthly Archives: August 2011

No Promoter is an Island: Methylation Affects Transcription Even Without CpG Clusters

Posted on August 26, 2011 by Chris Womack

Last week I stumbled on an interesting finding–or so it seems to me. Even genes whose promoters aren’t near CpG islands can be regulated by DNA methylation. Previous research seemed to point to the idea that CpG islands–short DNA stretches containing lots of two-nucleotide cytosine-guanosine sequences–were necessary for controlling nearby transcriptional promoters. Methylating a CpG island turns a gene off–shutting down RNA transcription from that site–while demethylating the island turns a gene on. And methylating CpGs in a CpG-poor promoter seemed to have little or no effect. About half of promoter sequences don’t have nearby CpG islands, which seems a little strange, since many of these promoters control genes that’re important only for specific tissues. After all, methylation is one … Continue reading →

Posted in DNA Methylation, Gene Regulation, Gene Silencing, Sodium Bisulfite Sequencing | Tagged , , | Leave a comment

To Succeed, Develop Your Talents Epigenetically

Posted on August 19, 2011 by Nicole Kelesoglu

While visiting Rio de Janeiro two weeks ago, I attended a soccer game. I’m not a big soccer fan. Yet there I was up on my feet, hollering. You just can’t help yourself. Brazilians are the best soccer players in the world! Inspired by that game, I read the book Bounce: Mozart, Federer, Picasso, Beckham and the Science of Success by the British, former ping pong champion turned journalist, Matthew Syed. The book presents evidence that success is driven primarily by effort, not genetics. Just the idea of innate talents, has a negative effect on motivation and success. Society would achieve more if everyone understood that expertise is concretely achievable – you are not just born with it. There are … Continue reading →

Posted in Behavioral Epigenetics, Biomarkers, Developmental Biology, Neuroscience | Tagged , , | Leave a comment

Acetylation of Histone Variant H2A.Z Gone Haywire!

Posted on August 4, 2011 by Nicole Kelesoglu

The practice of making poor repairs with hay wire – wire used to bale staw – originated the slang phrase. It means non functioning or acting just plain crazy. We can now view H2A.Z as the histone variant that can go haywire. Dr. H Valdés-Mora and colleagues at the Garvin Institute of Medical Research in Sydney, an Epigenetics team headed by Susan Clark, have untangled the meaning behind seemingly conflicting published results. Pattern changes in the acetylation states of promoter-associated H2A.Z, are demonstrated as a mark of cancer-specific gene deregulation. Acetylated H2A.Z is exclusive to the epigenetic silencing marks of Trimethylate histone H3 on lysine 27 (H3K27me3) and/or DNA methylation. In prostate cancer, acetylated H2A.Z “was associated with oncogene activation … Continue reading →

Posted in Acetylation, Biomarkers, DNA Methylation, Histone Modifications, Histones, Oncology | Leave a comment