Periodic Reporting for period 1 - INTERCOM (Mitochondria-ER communication by contact sites during plant stress responses)
Reporting period: 2023-09-01 to 2025-08-31
The INTERCOM project sought to deepen our understanding of plant inter-organelle communication, specifically focusing on ER-mitochondria interactions. The mechanism by which plant intracellular organelles interact in response to stress signals is still an underexplored area of plant stress sensing, and addressing this knowledge gap is crucial for enhancing our ability to engineer plants more resilient to adverse environmental conditions. The objectives of the project included establishing a proteomic setup in planta to identify novel membrane contact sites (MCS) proteins, developing a platform to study inter-organelle interactions in vivo, and identifying stimuli driving MCS dynamics. Despite the early termination of the grant, significant progress was achieved, including the establishment of valuable tools not only to advance the overall aim of the project but also to benefit the broader scientific community. In addition, the project also contributed to strengthening the transversal skill set and competencies of the researcher, Dr. Elena Sanchez Martin-Fontecha.
During the 13-month duration of the INTERCOM project, a Bimolecular Fluorescent Complementation (BiFC)-based screening was established in planta to explore novel ER and mitochondria anchoring proteins by live-cell imaging. This approach led to the discovery of new ER-mitochondria inter-organelle interaction reporters suitable for in vivo studies. Also, the genetic tools required to study stress-responsive membrane contact site (MCS) dynamics in Arabidopsis were developed.
In addition, a cutting-edge proteomic tool was implemented and optimized for interactomics studies in both cell cultures and Arabidopsis transgenic lines. This technology combines proximity labelling with protein-fragment complementation assays, allowing the precise characterization of protein complexes by the specific identification of protein-protein interaction-dependent partners. Furthermore, a MCS-specific proteomic screening was established by integrating the proteomic tool with the novel inter-organelle interaction reporters. Using this comprehensive approach, several novel MCS protein candidates were identified through mass spectrometry, providing a foundation for future validation and detailed characterization.
In addition, a cutting-edge proteomic tool was implemented and optimized for interactomics studies in both cell cultures and Arabidopsis transgenic lines. This technology combines proximity labelling with protein-fragment complementation assays, allowing the precise characterization of protein complexes by the specific identification of protein-protein interaction-dependent partners. Furthermore, a MCS-specific proteomic screening was established by integrating the proteomic tool with the novel inter-organelle interaction reporters. Using this comprehensive approach, several novel MCS protein candidates were identified through mass spectrometry, providing a foundation for future validation and detailed characterization.
The project has established several biotechnological tools that not only contribute to the study ER-mitochondria interactions but also benefit the broader research community. The proteomic tool implemented in planta adds up to the methodologies already available for plant interactomics studies, while the novel inter-organelle interaction reporters expand the limited toolkit for plant MCS research. In addition, the project generated a shortlist of potential MCS proteins, establishing the groundwork for future investigation into their role in ER-mitochondria interactions.
However, future research is needed to uncover the mechanisms underlying inter-organelle interactions and their physiological relevance during plant stress responses. This knowledge is essential to fully understanding the role of ER-mitochondria communication in plants, and has the potential to boost our ability for crop improvement and adaptation to the environmental challenges that climate change poses.
However, future research is needed to uncover the mechanisms underlying inter-organelle interactions and their physiological relevance during plant stress responses. This knowledge is essential to fully understanding the role of ER-mitochondria communication in plants, and has the potential to boost our ability for crop improvement and adaptation to the environmental challenges that climate change poses.