Irvine, Calif., April 8, 2026 — Carnivorous plants look like they run on instinct: catch an insect, digest it and absorb nutrients. But for scientists, a core question has remained difficult to answer: how does a plant “know” it has caught prey, and how does it decide which chemical tools to deploy next? Getting those right matters. Plants are expert chemists and understanding how they switch specific enzymes and protective compounds on and off can help researchers discover new lab tools and identify natural molecules that could someday help defend against harmful microbes.
In a new study published in Plant Physiology, UC Irvine researchers from the lab of Professor Rachel Martin at the Charlie Dunlop School of Biological Sciences, in collaboration with Professor Carter Butts at the School of Social Sciences, identified two distinct stages in the feeding cycle of the Cape sundew (Drosera capensis). One stage is triggered by a signal that tells the plant prey has been caught; the other depends on the nutrients the plant actually has available from what it captured. To tease those stages apart, the team compared what happens when the plant receives a “prey detected” signal with what happens when it receives different kinds of food inputs, including pure protein and whole insect material. By tracking both gene activity and the plant’s changing mix of small molecules during feeding, the researchers found that some responses are turned on by the signal alone, while others only appear when the plant has the right raw ingredients from prey.
Martin said that separating “signal-driven” chemistry from “nutrient-driven” chemistry helps explain why carnivorous plants don’t simply flip a single switch when prey arrives — they also appear to tailor what they make to what they can build from the meal. “I think the most compelling aspect of this work is that it enables us to start to understand which enzymes and small molecules a carnivorous plant can make in response to a signal indicating that it has caught prey, and what it needs raw materials from the prey to make,” said Martin. “For example, the plant can make pigment molecules when it is fed on pure protein, but not lipids. For those, it needs whole insect prey. Having detailed information about the metabolism, and which compounds are upregulated in response to feeding can guide us toward new digestive enzymes that can be used as laboratory tools as well as new small molecules for defense against bacterial and fungal pathogens.”
The work also required building order from a system that is still relatively unmapped. Co-first author Gemma Takahashi, PhD, focused on connecting the plant’s genetic activity to the chemicals it produced, even when many genes did not come with clear labels. “The Drosera capensis transcriptome is still relatively unexplored,” said Takahashi. “A huge portion of our time was spent adding functional annotations to our genes, verifying the identities of our small molecules, and summarizing our findings in a way that could be visualized in a manuscript … I think it was quite a creative way to make sense of what was otherwise relatively unexplored data.”
Co-first author Zane Long, PhD, pointed to the next frontier: identifying many still-unknown molecules detected during the feeding cycle — which could include compounds new to science. “The most significant challenge remains obtaining high confidence structural IDs for a large chunk of unknown small molecules detected during analysis,” said Long. “These could be new, unique structures which haven’t been reported, or they could be known molecules which we didn’t have the evidence necessary to identify … ultimately we need alternate modes of ionization and fragmentation, as well as consecutive fragmentation to better characterize those still unknown molecules.” In other words, the team says more powerful chemical “fingerprinting” approaches will be key to naming what the sundew is making.
The study reflects a collaborative effort that included significant contributions from Franchesca Cumpio, who worked on the project as an undergraduate researcher.
Looking ahead, the researchers say this clearer picture of how carnivorous plants manage digestion and defense could guide future searches for useful enzymes and natural compounds, with potential downstream benefits for biomedical research and more sustainable approaches to managing bacterial and fungal threats. The team encourages continued support for basic research — because understanding how nature solves problems is often the first step toward translating those solutions for the public good.
About the University of California, Irvine Charlie Dunlop School of Biological Sciences:
Recognized for its pioneering research and academic excellence, the Charlie Dunlop School of Biological Sciences plays a crucial role in the university’s status among the nation’s top 10 public universities, as ranked by U.S. News & World Report. It offers a broad spectrum of degree programs in the biological sciences, fostering innovation and preparing students for leadership in research, education, medicine and industry. Nestled in a globally acclaimed and economically vibrant community, the school contributes to the university’s impact as Orange County’s largest employer and a significant economic contributor. Through its commitment to exploring life’s complexities, the Dunlop School embodies the UC Irvine legacy of innovation and societal impact. For more on the Charlie Dunlop School of Biological Sciences, visit https://www.bio.uci.edu/.