Do Mushrooms Call for Rain? ― The Impact of Fungal Proteins That Freeze Water

Fungi are known for enriching soil, decomposing fallen leaves, and sometimes adding color to our dining tables. However, the recent study suggests that these fungi might possess a more unexpected ability—the "switch to freeze water." Reported by Phys.org on March 12, 2026, the study reveals that fungi of the Mortierella family produce special proteins that efficiently promote ice formation.

Ordinarily, pure water doesn't necessarily freeze at 0 degrees. Under certain conditions, it can remain liquid at much lower temperatures. When a substance acts as a "nucleus," ice begins to form rapidly. This ability to trigger "ice nucleation" has been well-studied mainly in certain bacteria. However, the research team demonstrated that fungi also have a similar mechanism, and in a rather sophisticated form.

According to the paper, the fungi studied possess membrane-independent, water-soluble ice-nucleating proteins. This is a significant difference from the well-known bacterial ice-nucleating proteins, which function while attached to the cell membrane. In contrast, the fungal proteins discovered dissolve in water and are considered relatively easy to handle. The research team sees this difference as a point that could lead to high applicability.

Even more intriguing is their origin. The research team believes that the genes in these fungi were likely transferred horizontally from bacteria long ago. In other words, fungi may not have evolved the same ability from scratch but instead incorporated bacterial "blueprints" and adapted them for their own use. Evolution is not a straight line; it sometimes involves "borrowing" necessary functions from other organisms. This study vividly demonstrates that dynamism.

In the paper, in addition to structural predictions and phylogenetic analysis, experiments were conducted where genes found in fungi were introduced into yeast and E. coli, which lack ice-nucleating ability. The modified microorganisms exhibited ice-nucleating activity, confirming that the discovered genes are indeed the source of this ability from a functional perspective. This research's strength lies in confirming the mechanism as an actual working system, not just the discovery of "similar sequences."

The reason this discovery is noteworthy is not just the biological surprise. Researchers first mention the potential for application in the field of meteorology. In clouds, whether water droplets turn into ice can trigger precipitation. In cloud seeding, particles that easily become ice nuclei are introduced into clouds to promote rain or snow. Traditional silver iodide, often used, raises toxicity concerns, but if fungal-derived proteins can be mass-produced, they could offer a safer alternative.

However, it's important to note that this is not about "immediately controlling the weather." Both the original article and the paper indicate that this is merely a potential future application. Cloud seeding is heavily influenced by cloud conditions and atmospheric conditions, and there are complex conditions for its implementation and evaluation. The significance of this discovery lies in finding a "new candidate substance," not in the rapid advancement of weather manipulation. It needs to be received without exaggeration.

Rather, the more realistic application areas of interest might be in food processing and cryopreservation. For example, in the production of frozen foods, when and how ice is made directly affects quality. The size and formation of ice crystals can change the texture and the way cell structures are damaged. Researchers believe that fungal-derived ice-nucleating proteins, which do not require the use of bacteria themselves and can use well-defined proteins alone, offer advantages in terms of safety and management.

There is also great anticipation in the fields of medicine and life sciences. When freezing cells, tissues, sperm, eggs, or embryos, the way ice forms can affect survival rates. If water remains excessively supercooled and suddenly freezes, it can cause severe damage to cells. The research team suggests that adding small, water-soluble fungal-derived molecules could help freeze surrounding water at higher temperatures first, protecting delicate internal cells. This is a significant implication for the fields of regenerative medicine and reproductive medicine.

Furthermore, this discovery also relates to climate science. The efficiency of ice nuclei in clouds affects cloud properties, radiation balance, and precipitation patterns. Researchers at Virginia Tech state that with the identification of these molecules, it will now be easier to investigate the extent to which such fungal-derived molecules exist in clouds, potentially aiding in the long-term improvement of climate models. The connection between fungal research and the physics of the sky is truly fascinating.

This study also embodies a different kind of "fungal essence." Fungi have long been organisms that slightly defy human imagination. They create vast networks underground, support ecosystems as decomposers, and sometimes provide medicines and food. Now, they are producing molecules that could be involved in ice and precipitation in clouds. It's not an exaggeration to say that this discovery expands the image of fungi from "unassuming but strong entities" to "invisible regulators of the Earth's system." This is not just news for mushroom enthusiasts but a story that makes us reconsider how organisms interact with the environment.

So, how is this being received on social media? At present, due to the short time since the article's publication, it's difficult to confirm explosive dissemination. On Phys.org, at the time of retrieval, there were 0 shares and 0 comments, indicating that it hadn't yet spread widely as general news. This is not uncommon for newly released science news, but it's not yet a "buzzing topic."

On the other hand, on X, posts introducing the paper's title have been observed, and the focus of reactions seems to be more on the "fungi utilizing bacterial-derived mechanisms" and "the potential applicability of being water-soluble" rather than on entertaining surprise. In search result snippets, "soluble fungal ice nucleators" and "bacterial ancestry" are highlighted, and accounts interested in research appear to be paying attention to both the fascination of evolution and technological applications.

Moreover, in the context of university and research institution public relations, the application to "controlled freezing" such as cryopreservation, food processing, and snow generation is more prominently featured as a relatively understandable advantage than cloud seeding. In German research public relations, the potential for cryopreservation of cells and organs, food processing, and artificial snow is organized, and on social media, it seems more likely to be shared as "biomolecules that design ice" rather than the sensational angle of "fungi that create rain."

This measured reaction is, in a sense, healthy. While the term "weather modification" carries a strong impact, it is also prone to misunderstanding. The value of this discovery lies in the first solid capture of the molecular entity of fungi's ice-making mechanism. From here, further verification will continue on how much can be mass-produced, the degree of stability and safety, and whether it truly has an advantage over existing technologies. It's not bad that social media is aiming to discern the practicality of applications rather than immediately swinging to "amazing" or "scary."

The most impressive aspect of this news might be the realization that "nature already possesses many technologies." For a long time, humans have considered operations like cooling, freezing, and preserving as issues of equipment and materials. However, organisms have been controlling the way ice forms at the molecular level long before that. Moreover, these blueprints have been passed across biological boundaries, improved, and are still at work today. The small protein of fungi connects rain in the sky, food quality, and the future of medicine in one line. In this light, this discovery is not merely a "story of unusual fungi," but news that might make us reconsider the boundary between life and matter.

Source URL

Phys.org
https://phys.org/news/2026-03-fantastic-fungi-ability.html

Science Advances published paper (primary research information. Checkpoints on fungal ice-nucleating proteins, horizontal gene transfer, and structure-function)
https://www.science.org/doi/10.1126/sciadv.aed9652

Virginia Tech news (press release by the research institution. Explains the paper's content to the general public and the potential for applications in cloud seeding and cryopreservation)
https://news.vt.edu/articles/2026/03/ice-nucleation-fungi-boris-vinatzer-xiaofeng-wang.html

idw / Max Planck Institute for Polymer Research press article (explanation from the research team. Supplementing the potential for applications in food processing, cryopreservation, and artificial snow with stable, water-soluble properties)
https://idw-online.de/en/news867496

Example of reactions on X (introducing the paper's title and confirming reactions focusing on soluble fungal ice nucleators and bacterial ancestry)
https://x.com/OrdoFibonacci/status/2031989239714627984