Parasite Manipulates Plant Cells to Attract Insects for Its Transmission

A bacterial parasite has been observed to influence plant cell behaviour in a way that enhances its own transmission through sap-feeding insects. This adaptation alters plant responses. It was observed that it attracts female insects to males already present, which promotes the parasite's survival. The discovery highlights a unique interaction among plants, bacteria, and insects, with significant implications for understanding how pathogens manipulate host biology for their benefit.

Study Links SAP54 Protein to Insect Behaviour

According to a study published in eLife, phytoplasmas—bacterial pathogens responsible for plant diseases—rely on effector proteins to facilitate transmission via leafhoppers. The research focused on SAP54, a virulence protein known to induce leaf-like flower structures on infected plants. It was revealed that SAP54 affects the feeding and reproductive behaviour of leafhoppers in a sex-dependent manner.

Dr. Zigmunds Orlovskis, an independent project leader at the Latvian Biomedical Research and Study Centre, explained to phys.org that previous research had shown leafhoppers were drawn to infected plants, but the mechanisms behind this attraction were unclear. Recent findings suggest that male leafhoppers play a key role in this interaction.

Female Attraction Depends on Male Presence

Experiments demonstrated that SAP54-altered plants hosted more leafhopper offspring, but only in the presence of males. Female leafhoppers exhibited increased feeding activity on SAP54 plants when males were present but showed no preference otherwise. Further investigations indicated that smell and sound did not influence the behaviour, leading researchers to focus on genetic changes in the plants.

Key Genetic Pathways Identified

As per reports in phys.org, it was found that SAP54 suppressed the plant's defence mechanisms, particularly when exposed to male leafhoppers. This suppression was linked to a transcription factor, SHORT VEGETATIVE PHASE (SVP), which appeared crucial for attracting females to male-colonised plants.

Insights into Parasite Strategies

Professor Saskia Hogenhout, Group Leader at the John Innes Centre, noted that the findings illustrate the parasite's ability to manipulate host and vector interactions, enhancing its life cycle efficiency. The study underscores the complexity of plant-pathogen-insect relationships and provides new insights into the strategies employed by parasites for survival and propagation.