Wednesday, April 25, 2018

Study reveals the inner workings of a molecular motor that packs and unpacks DNA

Precision, complexity, organization, heavy duty, astounding , react rapidly to alterations in their environment - all through BUC.

The more we learn the harder it is for evo proponents to advocate with a straight face. It looks designed but we know it isn’t. :grinning:

Study reveals the inner workings of a molecular motor that packs and unpacks DNA
Moreover, the entire DNA must be replicated before cell division and DNA damage needs to be repaired.

This is when chromatin remodelers come into play. Chromatin remodelers have an essential role as they are molecular machines: they unpick and unpack segments of the DNA by sliding nucleosome spools back and forth, replacing individual histones, freeing up the DNA for transcription, and finally compacting it again, when the job is done. Since all of this happens in a highly dynamic fashion, chromatin remodelers enable cells to react rapidly to alterations in their environment – and this holds for brewer’s yeast as well as for human cells. In mediating gene accessibility, chromatin remodelers are vital for development and cell differentiation; cell types are defined by the sets of genes they express, remodelers help to determine cell identity.

From a biochemical point of view, remodelers are responsible for heavy-duty reorganizational tasks. To perform these tasks, they must execute “large-scale conformational changes, which are carried out with astounding precision,”

The clouds of spaghetti that keep DNA data safe

The clouds of spaghetti that keep DNA data safe

Cells can avoid “data breaches” when letting signaling proteins into their nuclei thanks to a quirky biophysical mechanism involving a blur of spaghetti-like proteins, researchers from the Rockefeller University and the Albert Einstein College of Medicine have shown. Their study appears in the March 23 issue of the Journal of Biological Chemistry.

In every human cell, all of the body’s blueprints and instructions are stored in the form of DNA inside the nucleus. Molecules that need to travel in and out of the nucleus – to turn genes on or off or retrieve information – do so through passageways called nuclear pore complexes (NPCs). Traffic through these NPCs must be tightly controlled in order to prevent DNA hijacking by viruses or faulty functioning as in cancer.

"How on Earth do you have the kind of specificity that we see in protein-protein interactions like antibodies, and yet have the kind of speed that we see with water off a Teflon pan?"

"I can’t think of any analogy in normal life that does what this does," Rout said. "You’ve got this blur of (amino acids) coming on and off (the transport factor) with extraordinary speed."