The week’s most astounding developments from the neobiological frontier.

September 22, 2022

Bionic bacteria

Researchers at the University of Bristol in England have developed a way to make a new type of synthetic cell by capturing and processing bacteria inside microdroplets. What emerges are fabricated “bionic” cells the researchers call “functional protoliving microdevices”—half living cell and half synthetic construct. They look more like amoeba than bacteria, and the researchers say they have potential applications in engineered synthetic biology and biotechnology. The bionic bacterial cells “could offer more complex modules for development in diagnostic and therapeutic areas of synthetic biology as well as in biomanufacturing and biotechnology in general,” they write. Nature

Rapamycin given to baby mice slows aging

We don’t just age when we’re old—it’s a lifelong process. In fact, the current best molecular analyses of aging mammals suggest our cells start to age even while we are in utero. Now a study at Harvard and Brigham and Women’s Hospital in Boston demonstrates that an early-life drug intervention given to mouse pups could extend life. The study involved feeding newborn mice rapamycin for the first 45 days of their lives. The mice grew slower, remained smaller their entire lives, reached reproductive age later, had just as many offspring—and lived 10 percent longer on average and were healthier. The same effect was seen in a similar study of the planktonic crustacean Daphnia magnaScience Advances

Transcendental meditation reduces burnout in health care workers

A randomized clinical trial of 80 health care workers during the COVID-19 pandemic at Duke University Medical Center in Durham, North Carolina, showed that people given a three-month transcendental meditation intervention had more chronic stress reduction and less burnout compared to controls who were given access to wellness resources. The special form of meditation, which involves silently repeating a single-word mantra, did not significantly reduce acute stress compared to controls, but its significant reduction of chronic stress suggests transcendental meditation could be an effective strategy to prevent hospital worker burnout, the authors write. JAMA Network Open

Frozen in fear: How scary memories persist in the brain

Normal fear can be a good thing—it’s an evolutionary-derived adaptation that instills a hot, cautionary prudence in our cold, cruel world. But excessive fear can be debilitating, the dry-tinder fuel of post-traumatic stress or anxiety disorders. Now researchers at Linköping University in Sweden have uncovered a key epigenetic mechanism by which the brain strengthens its grip on fear memories. They showed in rats how fear expression is enhanced through a novel mechanism involving the downregulation of a protein known as histone methyltransferase PRDM2, which increases the strength of scary memory consolidation in the brain. The study also suggests a new brain mechanism that accounts for pathological fear memories in people with alcohol use disorders. Molecular Psychiatry

$126 million grant to study aging brain

The Salk Institute in La Jolla, California, announced today it was selected to lead a $126 million effort from the National Institute on Aging to study the molecular fate of human brain cells as we age. Part of the NIH’s Brain Initiative, the grant will fund a project to collect a total of 1,500 brain samples from 30 people who range in age, sampling 50 brain regions from each person. The project will classify the cells found in those regions more precisely than ever before, based on molecular markers, and compare across age groups to gauge how those markers change from early life to old age. Press announcement

A cross-section of the middle temporal gyrus region of a male human brain that uses spatial transcriptomics, a technique that distinguishes cells by their genetic data and uses that information to map the cells back to their original locations. Salk Institute and UC San Diego

How ketogenic diets change metabolism in the brain

Our brains are filled with billions of neurons engaging in energetically expensive signaling, a demand our bodies normally fill by using glucose as an energy source. Glucose is partly replaced when people consume a low-carbohydrate, high-fat ketogenic diet, but it’s not clear how the brain responds to the changing fuel supply. So researchers at the Max Planck Institute for Multidisciplinary Sciences in Göttingen, Germany, analyzed the proteomes of cells taken from the central nervous systems of young and old mice fed ketogenic diets or subjected to neuroinflammatory disease. They found the five major cell types in the brain use distinct strategies to manage altered nutrition or respond to neurological disease—revealing key mechanisms of metabolic brain remodeling that “confer an advantage in neuroinflammatory disease,” the researchers write. Science Advances

Let the gametes begin!

The longstanding mind’s-eye view of sperm as an army of individual bro cells competing in a winner-take-all elimination race to fertilize a woman’s egg may be completely wrong. As it turns out, the winners may be the ones that swim the most cooperatively, according to a provocative new hypothesis from researchers at North Carolina A&T State University and Cornell University. Setting up a series of microfluidics experiments using bull sperm, they showed that clustered sperm swim better, like schools of fish heading upstream or teams of bicyclists forming drafting pelotons. The observation may help improve IVF or other assisted-reproduction technologies in the future. Frontiers in Cell and Developmental Biology

Coexistence of individually swimming and clustered sperm. Clustered sperm are labeled with yellow ovals. S Phuyal, SS Suarez, C-K Tung