Sunday, June 18, 2006

Brightsurfing   posted by Coffee Mug @ 6/18/2006 11:54:00 PM

I just discovered a news service called Brightsurf that collects science press releases. At the same time, I was irritated to discover that my RSS feeds for Cell and Neuron don't update immediately when the new issues come out. So the new Neuron has been out for 4 days, and I was in the dark. Mainly I wanted to point out that the new Cell came out, and it has a bunch of cool articles in it, three of which are accompanied by press releases.

I hope to have time to dissect some of these articles in detail. One shows a change in a certain allele in the lineage of HIV-1 that used to inhibit T-cell death. This is apparently why SIV in most cases is harmless. I know absolutely nothing about this, but it suggests to me that one route to treatment might be rather than trying to block viral entry into cells to attempt to mimic this lost viral function by knocking down the gene that the virus used to knock down on its own, called TCR-CD3.

Two papers, that didn't get press releases, discuss RNA regulation pathways in detail. One dissects the pathway by which RNAs that were transcribed wrong get targeted for destruction in P-bodies, while another shows how sometimes RNAs that get targeted to P-bodies don't get destroyed at all. This latter has been foreshadowed in the literature for a while. This would provide a more flexible control of translation by miRNAs, so they could just trap their targets for a while and release them at the appropriate time (much faster response to environmental inputs than having to transcribe the whole thing again).

Another paper showcases a fancy technique known as an "optical trap" whereby single molecules can sorta be frozen in place, so we can take a look at them. Nanotechnology is really starting to pay off in the molecular biology world, so it's probably time I start wrapping my head around how this stuff actually works. They use the technique to discover specific DNA sequences that induce RNA polymerase 'pausing'. RNA polymerase turns out not to read DNA seqences off all smooth-like, but instead coughs along in fits and starts, more like Fozzy Bear's jalopy than a new Caddy. Until now, it had to be chalked up to "noise", but now we can start actively pursuing the physical mechanisms.

And finally, I have to point out how egregious this press release is. Compare the headline to the article title:
Headline: Cure found for Huntington disease in mice offers hope for treatment in humans

Article: Cleavage at the Caspase-6 Site Is Required for Neuronal Dysfunction and Degeneration Due to Mutant Huntingtin
Cure found for Huntington's disease?! Awesome! Oh wait, it's just a really cool paper discovering more about the mechanisms by which abnormal huntingtin protein leads to neural pathology. Huntington's disease is one of a few that has been traced down to abnormality in a single gene. The gene has a big chunk of sequence added to it that causes the protein to contain a long string of glutamine residues. I was unaware that mutant huntingtin gets chopped up by cellular proteases and that these cleavage products accumulate early in the disease process. The article shows that, at least in mice, blocking this cleavage step blocks the rest of the disease. This does provide a target modification we might like to make in the genes of Huntington's patients, but we had one of those already (remove the polyglutamine sequence). The hard part is going to be getting a gene therapy vector to neuronal populations and changing the sequence without negative side effects. I'm not discounting the importance of the paper, this may prove an easier change to make, but it might almost be considered cruel to start a headline with "Cure for Huntington disease.." when it is really only one more incremental step in the long process. Am I being too demanding/nit-picky?

Anyway, Brightsurf looks like a good resource for those that didn't know about it already. Lots of interesting stuff coming out. I'll get back to packing info into ye olde noggine now. Probably won't be starting in on a novel this week.