Friday, September 26, 2008

H2A.Z and DNA Methylation

A Nature paper Histone H2A.Z and DNA methylation are mutually antagonistic chromatin marks, authored by Daniel Zilberman, Devin Coleman-Derr, Tracy Ballinger and Steven Henikoff (doi:10.1038/nature07324; published online 24 September 2008) explores the transcription process and DNA methylation. Methylation is involved in the suppression of gene transcription. Non-functional methylation patterns have been associated with cancer.

The paper refers to H2A.Z, a histone variant, which "promotes transcriptional competence." H2A.Z and DNA methylation dynamics are not completely understood. The plant Arabidopsis thaliana was used to study DNA methylation. H2A.Z and DNA methylation appear to have opposing effects. While the presence of H2A.Z inhibits DNA methylation, its absence can signal gene silencing.


Wednesday, September 24, 2008

Furthering Our Understanding of the Histone Code

In the recent issue of Nature Reviews Molecular Cell Biology (9, 815-820, October 2008) authors Robert J. Sims 3rd and Danny Reinberg ponder the histone code hypothesis. The piece is titled Is there a code embedded in proteins that is based on post-translational modifications? The issue has design implications in my view. From the abstract:

Covalent post-translational modifications (PTMs) provide vast indexing potential and expanded protein use. The 'histone code' hypothesis has inspired rapid advances throughout chromatin biology, and has recently been tapped for its relevance to non-histone proteins. Comprehensive analyses suggest that rather than constituting a general code, the covalent modifications of proteins (including histones) provide surfaces that are recognized by effectors that can give rise to intricate interactions and downstream events. These are reminiscent of other regulatory cascades in transcription and cell signalling.


Monday, September 15, 2008

Intellectual Snobbery

Not surprisingly Sarah Palin has been heavily criticized in the blogosphere. That includes ID blog Telic Thoughts where some have been very aggressive. Charles Krauthammer wrote Charlie Gibson's Gaffe. The whole article is linked to but I particularly liked the way he concluded. Krauthammer:

Presidential doctrines are inherently malleable and difficult to define. The only fixed “doctrines” in American history are the Monroe and the Truman doctrines which come out of single presidential statements during administrations where there were few other contradictory or conflicting foreign policy crosscurrents.

Such is not the case with the Bush doctrine.

Yes, Sarah Palin didn't know what it is. But neither does Charlie Gibson. And at least she didn't pretend to know -- while he looked down his nose and over his glasses with weary disdain, sighing and “sounding like an impatient teacher," as the Times noted. In doing so, he captured perfectly the establishment snobbery and intellectual condescension that has characterized the chattering classes’ reaction to the mother of five who presumes to play on their stage.

Unlike scientific doctrines political doctrines are intrinsically difficult to define, as Krauthammer suggests. That in turn indicates that questions about political doctrines contain an inevitable amount of imprecision, sometimes leading to lack of clarity.

Snobbery and intellectual condescension come through loud and clear in the daily attacks against Palin. Unfortunately, Gibson is merely one of many offenders. But the labels her critics try to pin on her will not stick. In fact, I think they will backfire and show Palin's accusers to be what many of them actually are- hostile, condescending snobs.


A Faster and Cheaper Way

TGen investigators devise faster, cheaper way of analyzing the human genome is a EurekAlert article. It reports that investigators at the Translational Genomics Research Institute had found a faster and less expensive means of locating genes important to human health. It involves genomic indexing to identify genetic variations. Cuts of up to ninety percent of what currently is required to sequence genes to analyze Single Nucleotide Polymorphisms (SNPs) may be possible according to Dr. David Craig, the associate director of TGen's Neurogenomics Division.

Saturday, September 06, 2008

Borking Palin through Unethical Reporting

Palin and Evolution is an excellent blog entry about Sarah Palin's much distorted views about teaching as it relates to creation and evolution.

If mainstream journalism had a shred of integrity left, prior to the designation of Sarah Palin as the vice-presidential candidate, it seems determined to shed it in the interest of unabashed and shameful political campaigning. There was a time when the reporting of news stories was guided by a sense of professional ethics. Reporters at least attempted to lay aside their personal preferences in an effort to report facts. No longer. What we witness now are distortions and selective reporting of facts to mold reader viewpoints rather than provide objective news. The mainstream media does not merit our trust. Sadly, it has become irrelevant as a reliable source for those interested in the truth.

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