Until recently, the color variations observed in the petals of Saintpaulia were attributed to periclinal chimera or the influence of genetically distinct cell layers. Now, a new study by researchers from Japan has identified a single gene called SiMYB2 that regulates petal colors in Saintpaulia by producing two distinct mRNA transcripts. This study lays the foundation for future horticulture-related research and can aid the deliberate breeding of patterned flowers.

The subducted oceanic crusts are regarded as the major source of lower-mantle heterogeneity. However, the limited knowledge about the physical properties of major components in the subducted oceanic crusts prevents us from fully understanding the complex features of the related geophysical anomalies. Here, we comprehensively investigated the phase transition of (Al, H)-bearing stishovite at simultaneously high P-T conditions. These results contribute to our understanding on the complex depth distribution of the mid-lower mantle seismic scatterers.

A research group led by The University of Osaka has discovered that the DNA repair enzyme Polβ plays a crucial role in protecting the developing brain from harmful mutations. The study found that a lack of Polβ leads to a significant increase in small insertions and deletions of DNA, known as indels near CpG sites, which are important regulatory regions in genes. This accumulation of mutations could contribute to neurodevelopmental disorders.

Plants and microbes often have a symbiotic relationship, relying on each other for nutrients or shelter. Understanding and engineering such symbioses is an essential step in the journey towards tackling global challenges such as food security, carbon capture and ecosystem restoration. Now in The ISME Journal, researchers at the Okinawa Institute of Science and Technology (OIST) have reported in depth on the symbiotic relationships and microbial communities within Azolla ferns, bringing new insights to these important plants.

What kind of personality would an AI develop if we gave it no roles, goals, or instructions—only basic human-like needs? This study explores how language-model agents form unique personalities through everyday interaction, without being programmed to do so. Inspired by human-needs theory, the work hints at ways to build virtual agents that interact more naturally with people. 

Rheumatoid arthritis (RA) is an autoimmune disease that affects millions worldwide and can have a devastating impact on patients’ lives. Yet, about one in three patients respond poorly to existing treatments. Researchers at Kyoto University have shed new light on this challenge by discovering that peripheral helper T cells (Tph cells), a key type of immune cell involved in RA, exist in two forms: stem-like Tph cells and effector Tph cells. The stem-like Tph cells reside in immune “hubs” called tertiary lymphoid structures within inflamed joints, where they multiply and activate B cells. Some of these then become effector Tph cells that leave the hubs and cause inflammation. This continuous supply of effector Tph cells may explain why inflammation persists in some patients despite treatment. Targeting the stem-like Tph cells at the source could offer a new therapeutic strategy, bringing hope for more effective symptom relief and improved quality of life for patients living with RA.

This research is led by Yuki Masuo, a doctoral student at the Graduate School of Medicine, Kyoto University; Associate Professor Hiroyuki Yoshitomi of the Department of Immunology (also Associate Investigator at WPI-ASHBi), Graduate School of Medicine, Kyoto University; and Professor Hideki Ueno, Vice Director and Principal Investigator at WPI-ASHBi (also Professor at the Department of Immunology, Graduate School of Medicine, Kyoto University, and Director of the Kyoto University Immunological Monitoring Center, KIC). These findings will be published online in Science Immunology on August 15, 2025, at 2:00 PM local time (August 16 at 3:00 AM JST).

Kyoto, Japan -- As space programs evolve and we continue to mistreat our own planet, human dreams of space tourism and planetary colonization seem increasingly common. However, features of spaceflight such as gravitational changes and circadian rhythm disruption -- not to mention radiation -- take a toll on the body, including muscle wasting and decreased bone density. These may even affect our ability to produce healthy offspring.

Studying the impact of spaceflight on germ cells -- egg and sperm precursor cells -- is particularly important because they directly influence the next generation, and any irreversible damage done to these will likely be transmitted to offspring. Previous examinations of embryonic stem cells that have undergone spaceflight have revealed abnormalities, but the exact cause of the damage has remained unknown.

This inspired a team of researchers at Kyoto University to test the potential damage to spermatogonial stem cells during spaceflight and the resulting offspring. The team utilized stem cells from mice, which have a much shorter reproductive life span than humans.

The Okinawa Institute of Science and Technology (OIST) Associate Professor Paola Laurino has been selected as one of the top 10 global awardees in the Life Sciences category of the Falling Walls Science Breakthrough, presented by Germany’s Falling Walls Foundation.  

Researchers in Japan have genetically transferred a unique courtship behavior from one fruit fly species to another. By turning on a single gene in insulin-producing neurons, the team successfully made a species of fruit fly (Drosophila melanogaster) perform a gift-giving ritual it had never done before. The study, published in the journal Science, represents the first example of manipulating a single gene to create new neural connections and transfer behavior between species.  

Kyoto, Japan -- For many endangered species, population decline to the brink of extinction leads to inbreeding, exposing a species to deleterious recessive mutations that severely limit its potential to recover. But the red-headed wood pigeon, endemic to the Ogasawara Islands in Japan, followed a different trajectory.

Although this pigeon population fell to below 80 individuals in the 2000s, it began to increase markedly after the removal of an introduced predator, the feral cat. Such a remarkable recovery raised questions regarding inbreeding, and why harmful mutations that could cause inbreeding depression, or a loss of genetic diversity, didn't hinder the species' revival.

In an effort to unravel this biological puzzle, a team of researchers at Kyoto University set out to investigate the factors that contributed to this unlikely comeback.