Astrocytes—but not neurons—in the amygdala encode anxiety-like states in mice, according to a paper published today in Neuron. The findings suggest that the cells—which are altered in people with some neuropsychiatric conditions, including autism—contribute to mental health difficulties documented in such groups. “In a very sophisticated way, the [study] shows that astrocytes are these core […]
Gene fix: In-vivo base editing can mitigate autism-like effects in mice carrying a variant of the CHD3 gene, according to a new paper. The variant, found in people with Snijders Blok-Campeau syndrome, causes altered sociability, cognition and motor coordination in mice. A TadA-embedded adenine base editor, delivered brain-wide via an adeno-associated virus, restored CHD3 protein […]
Tickle test: Sensory learning is altered in a mouse model of fragile X syndrome, according to a new preprint. The investigators recorded neuronal activity in response to repeated whisker stimulation in the mice and observed hampered long-term potentiation—synaptic changes that underlie learning—in pyramidal neurons. The researchers speculate that these findings may reflect “a significant deterioration […]
Autism-related behaviors and susceptibility to seizures both arise from hyperactivity in a key region of a sensory-information-processing circuit in the brain, a new study finds. The results may help explain the frequent co-occurrence of autism and epilepsy and point to a new therapeutic target. According to current estimates, about 12 percent of people with autism […]
Butterfly effect: Disabling the ATRX gene in forebrain excitatory neurons during embryogenesis alters brain size, structure and connectivity in adult mice, according to a new preprint. Previous work has shown that this intervention induces autism-like behaviors and thus appears to model ATR-X syndrome in people. ATRX-deficient mice of both sexes were smaller than controls, but […]
Scratch the surface: Mice carrying a particular SHANK3 variant display heightened scratching behavior in response to a skin insult, according to a new study that attempted to model the altered sensitivity to touch observed in many autistic people. Electrophysiological analysis of sensory neurons revealed a decrease in mechanoreceptor responsiveness in the SHANK3 mice compared with […]
Visual cues: Sensory neurons in the retina display altered structure and function in a mouse model of fragile X syndrome, according to a new study. Retinal ganglion cells—homologous to primate ganglion cells—received more inhibitory input and were less responsive to light in mice lacking the gene FMR1 compared with the same cells in wildtype mice. […]
Ready riser: Mouse cells that harbor a bioluminescent version of MECP2 also express a red fluorescent tag after pharmacological reactivation of the X chromosome (bottom), which is normally silenced. Courtesy of Mira-Bontembal and Tan, et al. A new mouse model may accelerate the discovery of gene-activating therapies to treat Rett syndrome, a condition related to […]
That’s a wrap: Mice that produce high levels of the molecule 4EPS (top) have atypically sparse brain myelin — the fatty substance that sheathes axons and conducts neuronal signals — compared with controls (bottom). Mice chemically coaxed to produce high levels of an autism-linked gut molecule have anxiety-like behavior and unusual patterns of brain connectivity, […]
Motion picture: The software tracks points on a mouse’s body, from the nose to the tip of the tail, to automatically measure aspects of gait and posture. New software uses machine-learning to automatically detect and quantify gait and posture from videos of mice moving around their cage. The tool could accelerate research on how autism-linked […]
Stacked effects: A gene mutation and immune stimulation together can render mice less social. Photography by Richard Drury Activating the immune system blunts social behaviors in mice missing a copy of the autism-linked gene SHANK3, according to a new study. But blocking TRPV4, a gene that encodes an ion channel involved in inflammatory responses, can […]
Exhale: In mice with a mutated copy of the TCF4 gene (right), nerve cells (pink) are in short supply compared to controls (left). Courtesy Daniel Mulkey The breathing difficulties in children with Pitt-Hopkins syndrome, a rare form of autism, stem from dysfunctional circuitry and a malignant sodium channel in the brain stem, according to a […]
