New studies reveal the complex world of bacterial epigenetics
DNA has a knotty problem. Thousands of times longer than the cell that contains it, this intricate strand of As, Ts, Gs and Cs must fold itself into a compact package. But the thin double helix molecule can’t jam itself in any which way, lest it wind up horribly knotted. What’s more, the cell needs certain segments of the strand—particular genes—to remain accessible to protein-making machinery while keeping others tucked away and turned off. It’s like playing Tetris with a tangled ball of yarn.
New studies by University of Michigan biochemists Ursula Jakob and Peter Freddolino reveal that interactions between DNA-binding proteins and an ancient molecule called polyphosphate help to switch bacteria’s genes on and off on a broad scale. Not only do these findings tell scientists more about such organisms’ basic biology, but they could also help researchers fine-tune genetically engineered bacteria for biotechnology—and even contribute to new antibiotics.
More similarities have emerged over the years. For example, eukaryotic cells attach chemical tags and proteins called histones to hide away parts of the genome. Last year Freddolino’s laboratory showed that bacteria use an analogous strategy: the researchers identified 200 regions in the Escherichia coli genome that are silenced using chemical tags and structures called nucleoid-associated proteins .
Recently, in Science Advances, Jakob and Freddolino showed that negatively charged polyphosphate binds to positively charged NAPs using a process called liquid-liquid phase separation, in which ultradense protein groups condense into tiny droplets. As more and more polyphosphate attaches to the NAPs, the normally scattershot structure of polyphosphate, NAPs and DNA becomes organized.
France Dernières Nouvelles, France Actualités
Similar News:Vous pouvez également lire des articles d'actualité similaires à celui-ci que nous avons collectés auprès d'autres sources d'information.
Tucson Medical Center to help patients understand their risk for hereditary cancerTMC has partnered with the Mayo Clinic to offer virtual genetic counseling.
Lire la suite »
Meet Your New Nightmare: Ancient Spider With A Tail Preserved in AmberThis ancient spider preserved in amber had a frightening appendage — a whip-like tail.
Lire la suite »
Where to Swim With the Sea Creatures That Inspired MermaidsThey may not be mermaids, but an encounter with these graceful animals is equally unforgettable
Lire la suite »
Scientists Detect Genetic Link Between Blood Test Results And Some Mental DisordersMental health disorders including depression, schizophrenia, and anorexia show links to biological markers detected in routine blood tests, according to our new study of genetic, biochemical and psychiatric data from almost a million people.
Lire la suite »