Qiang Li and colleagues have created “cyborg” pancreatic organoids that combine stretchy miniature electronics with stem cell-derived pancreatic islets, using the implanted electronics to monitor electrical activity related to glucose regulation in maturing α and β cells. Islet α and β cells secrete glucagon and insulin hormones, in response to electrical changes in the cell membrane. The researchers also used the electronics to stimulate the cells to enhance their glucose responsiveness and show how that responsiveness changes as the cells mature, how it is affected by different chemical compounds and circadian hormones, and how it is related to gene expression. Together, the cyborg organoids offer a path to study the biology and trace the maturation of α and β cells at the single-cell level, with an eye toward potentially treating or engineering new pancreatic islets in people with diabetes. In a related Perspective, Jochen Lang and Matthieu Raoux discuss how the cyborgs could be used to guide the growth of mature human pancreatic organoids for regenerative medicine and other applications.

A new Spinosaurus species uncovered in northern Niger by Paul Sereno and colleagues appears to have been a wading predator of fish like its close relatives, but it lived as many as 1,000 kilometers inland from the Tethys Sea. The fossil find may represent a third phase of evolution for this group of massive, fish-eating dinosaurs, according to Sereno et al. The new species Spinosaurus mirabilis, uncovered in the central Sahara near Sirig Taghat (“no water, no goat” in Tamasheq, the local Berber language), lived with long-necked dinosaurs in a riparian habitat 100-95 million years ago. Sereno et al. suggest there were three phases of spinosaur evolution: a first phase that began in the Jurassic Period when the reptiles developed their elongated skull for fish-catching; a second Early Cretaceous Period phase that saw the spread of spinosaurs as predators all along the coast of the Tethys Sea; and a third phase where spinosaurs like S. mirabilis specialized as shallow water predators in northern Africa and South America. S. mirabilis was similar in size and skeletal form to Spinosaurus aegyptiacus, but was crowned with a unique scimitar-shaped bony crest that may have been used for visual display rather than locomotion or hunting.

Centromeres play virtually the same central role across the entire tree of life: They ensure the faithful segregation of chromosomes during cell division. Yet the striking diversity in centromere architecture – from large, repeat-rich DNA arrays to the minimalistic “point” centromeres in yeast – combined with their rapid evolution has puzzled scientists for decades. A research team led by Andrea Musacchio, Director at the Max Planck Institute of Molecular Physiology in Dortmund, and Jef Boeke from the NYU Grossmann School of Medicine have now solved the enduring mystery about the yeast centromere’s origin and evolution. They have identified a “proto-point” centromere that bridges the gap between the actual tiny “point” centromere and its more elaborate ancestor that incorporated fragments of parasitic DNA. This discovery reveals one of the most dramatic evolutionary transitions at DNA level

Researchers at The Jackson Laboratory and the University of Pennsylvania found that endurance gains from exercise are driven not just by muscles, but by specific neurons in the brain’s hypothalamus. Reporting in Neuron, the team showed that mice lacking activity in these neurons failed to build endurance, even with intense training. Conversely, artificially activating the neurons after exercise enhanced endurance gains. The findings challenge the traditional view that muscle adaptation alone explains improved fitness, highlighting a critical brain–body connection in how exercise builds stamina.

UVA Health researchers have identified a group of nerve cells in the brainstem that act as a stabilizing system for blood pressure. The findings could open the door for new treatments to overcome harmful effects of short-term blood pressure fluctuations in patients whose blood pressure otherwise appears normal.

Researchers from the University of Southern Denmark and Odense University Hospital have discovered a previously undescribed virus in a common gut bacterium. The virus appears more frequently in patients with colorectal cancer.

Researchers at Amsterdam UMC have discovered that a second pregnancy alters the female brain. Previous research from the same group had already demonstrated the impact of a first pregnancy on the female brain. These results are published today in Nature Communications. The research demonstrates that both a first and a second pregnancy have a strong and unique impact on mothers’ brains.