Mechanism behind Plant Memory has been Unraveled

A study conducted by scientists from the University of Nottingham and the University of Birmingham, in collaboration with researchers from the Universities of Oxford and Utrecht uncovered the mechanism that allows plants to remember changes in their environment. To figure out how plants sense and ‘remember' changes in their environment, the scientists focused on the polycomb repressive complex 2 (PRC2) protein, which is known to play a key role in cell identity, developmental transitions, and the establishment of environmental memory. Plants have different versions of this PRC2 protein that are responsible for different functions. For example, VRN2-PRC2 regulates vernalization in which certain genes are silenced upon long-term exposure to cold thereby encoding a memory of cold. The research team discovered that the VRN2 protein directly senses and responds to signals from the environment, but the protein is extremely unstable and broken down when it is not required, therefore, the PRC2 also remains inactive until required. However, the protein accumulates under suitable conditions. The VRN2 protein was previously identified as a positive regulator of vernalization, but scientists have now explained the "proteolytic mechanism" behind the environmentally-induced accumulation of VRN2 in response to cold temperatures specific to flowering plants. (Source: Crop Biotech Update, International Service for Acquisition of Agri-Biotech Applications. www.isaaa.org)