Quest for Sex Vs. Quest for Cancer Cures and Ageing Blockers

In an attempt to catch up on biological research news, there will be two findings discussed in this posting. First, this bio.com newsreport discusses a dramatic finding that the cell division cycle is reversible!

Gorbsky's findings appear in the April 13 issue of the journal Nature.

"No one has gotten the cell cycle to go backwards before now," said Gorbsky, who holds the W.H. and Betty Phelps Chair in Developmental Biology at OMRF. "This shows that certain events in the cell cycle that have long been assumed irreversible may, in fact, be reversible."

Cell division occurs millions of times each day in the human body and is essential to life itself. In the lab, Gorbsky and his OMRF colleagues were able to control the protein responsible for the division process, interrupt and reverse the event, sending duplicate chromosomes back to the center of the original cell, an event once thought impossible.

"Our studies indicate that the factors pointing cells toward division can be turned and even reversed," Gorbsky said. "If we wait too long, however, it doesn't work, so we know that there are multiple regulators in the cell division cycle. Now we will begin to study the triggers that set these events in motion." Source.

Obviously this finding can have immense repercussions in treatments for cancer, ageing, and other conditions involved in dysfunction of cell division.

The second news finding discussed in this posting, is the discovery of the protein SUMO, in its role in genome-wide gene silencing in yeast.

Most of the time in most cells of the body, the great majority of genes are silenced, locked away within the compacted but orderly material that makes up chromosomes. Estimates are that only about 10 percent of the roughly 25,000 genes in the human genome are activated, or "on," at any given time in a particular cell – the default setting for most genes is "off," or repressed.

Reliable gene silencing is vital to the health of an organism. Improperly activated genes can and do lead to cancer, for example. Gene silencing is also thought to protect the genome from viruses and other potentially damaging entities, thus preserving genetic integrity.

In a new study, researchers at The Wistar Institute and colleagues have identified an important new global mechanism for this essential gene silencing, or gene repression. A report on the findings appears in the April 15 issue of Genes & Development.

"We've discovered what looks to be an evolutionarily ancient mechanism for broadly repressing and protecting the genome," says Shelley L. Berger, Ph.D., the Hilary Koprowski Professor at The Wistar Institute and senior author on the study. "We believe it to be the first identified mechanism of its kind."

The new mechanism centers on histones, relatively small proteins around which DNA is coiled to create structures called nucleosomes. Compact strings of nucleosomes, then, form into chromatin, the substructure of chromosomes.

.....The research team also noted a dynamic interplay between the addition of a SUMO protein to a histone – sumoylation – and the addition of either an acetyl group or a ubiquitin protein to a histone. The processes appear to be mutually exclusive.

"Acetylation and ubiquitylation have both been shown in earlier studies to activate gene expression," says Kristin Ingvarsdottir, co-lead author on the Genes & Development study. "Sumoylation, on the other hand, is involved in gene repression, so it makes sense that it might exist in an either/or relationship with acetylation or ubiquitylation."

Another observation made during the study was that slightly higher levels of sumoylation occur near the tips of the chromosomes, the telomeres, which are known to play a central role in maintaining genomic stability. Instability in the telomeres has been linked to aging in humans and an elevated risk for aging-related diseases, the most prominent of which is cancer. Source.

So SUMO the grappling protein may play a role in cancer and ageing as well, if what takes place in yeast has a parallel in mammals. Fascinating.

The blog stats from my recent posting on sex dolls and sex robots revealed that most web surfers would rather read about sex than about cures for cancer or ageing. In fact, I had to change the name of the post to stop the deluge of worldwide sex surfers from overwhelming the statistics. Just a bit of web psychology--if you want to bring a lot of "hits" to your site, just put the word "sex" in the title of your posting.