Genome complexity: DNA repair mechanisms; wiggles (Introduction)

by David Turell , Sunday, November 08, 2015, 00:08 (3091 days ago) @ David Turell

To facilitate repair DNA wiggles!-http://phys.org/news/2015-11-dna-strands-wiggle-genetic.html-"Sometimes, the molecules that make up life exhibit strange behavior. For instance, in simple organisms such as yeast, when genetic material becomes damaged, the affected DNA strands increase their motion, waving about inside the cell like a sail unfurled. -***-"New research by Rockefeller University scientists shows the swaying of strands is, in fact, a pervasive part of DNA repair in mammalian cells. -***-"'This paper shows that an increase in physical mobility of DNA strands is something that happens inside mammalian cells every time there is a break in the DNA," says de Lange, who is also American Cancer Society Professor, and Director of the Anderson Center for Cancer Research at Rockefeller. "These breaks—and the subsequent increase in DNA mobility—can happen as a result of problems during DNA replication, chemotherapy, and other causes.'"-***-"Since that study, de Lange and postdoctoral fellow Francisca Lottersberger in her lab have identified the cellular structures involved in increasing DNA mobility after damage. One of those structures is embedded in the nuclear envelope, the barrier surrounding the chromosomes. Surprisingly, the second structure that boosts mobility in damaged DNA—microtubules—resides outside the nucleus, in the cytoplasm. Microtubules are highly dynamic rods that can move things around inside the cell, but can also poke the nucleus. Somehow, the microtubules interact with the nuclear envelope to send a signal to increase mobility of damaged DNA.-***-"The next step, de Lange says, is to try to find out why DNA mobility increases following damage. One possibility, she proposes, is that the process serves as a "fail-safe mechanism" when normal repair processes don't work: The more the broken strands move around, the bigger the chances are of them finding each other again, and repairing the break."-Comment: As with everything I've presented, these molecules seem to know what they are doing. I think they are controlled by onboard instructions. I fully expect more research will show that.