Melissa Magerøy
Research Scientist
Biography
I am a molecular biologist and biochemist focused on plants. During my bachelor’s degree, I researched light responses in cucumber and Arabidopsis. I completed my PhD at the University of Florida, studying flavor-related molecules in tomato. I then worked as a postdoctoral researcher at the University of British Columbia, investigating insect defense mechanisms in spruce. I am now continuing this work at NIBIO by studying the epigenetic mechanisms of defense priming and how priming can be used in integrated pest management. I am also passionate about training young researchers and have been an advisor for many master’s and PhD students. My areas of expertise include plant defense, molecular biology, plant biochemistry, epigenetics and functional genomics.
Abstract
Abstract Defence priming enhances plant responsiveness to future stress following prior exposure, and has been extensively characterised in annual model species as a reversible state associated with faster or stronger defence activation. However, studies in long-lived plants indicate that priming responses can be elicitor-specific, developmentally variable and closely linked to environmental history. In trees, priming is often strongest in early life stages, while in mature individuals defence responses are more frequently associated with direct activation and stabilised regulatory states. Evidence across systems shows that priming can operate over multiple timescales, from short-term reversible responses to longer-lasting effects that influence response thresholds and activation kinetics. Epigenetic mechanisms, including DNA methylation and chromatin modification, contribute to these processes and may persist across cell divisions or developmental transitions. Together, these findings highlight the importance of developmental stage and temporal context in shaping plant defence responses.
Authors
Theresa Weigl Jorunn Børve Melissa Magerøy Hanne Larsen Carl Gunnar Fossdal Siv Fagertun RembergAbstract
The physiological disorder soft scald may cause losses in apple fruit storage. This study aimed at understanding the interplay between fruit maturity at harvest and storage temperature on soft scald development in the susceptible cultivar ‘Red Aroma’. Fruit harvested late and subsequently stored at −0.5 °C developed the significantly highest soft scald incidence. Overall ethylene and CO2-production was reduced in late harvested fruit stored at −0.5 °C, while fruit from the early harvest showed a cold-induced ethylene increase under the same storage conditions, suggesting an active cold-acclimation response. Clustering of RNA sequencing data and overrepresentation analysis revealed that transcripts involved in cell wall modification, ripening-associated signaling, antioxidant defense system and secondary metabolism were upregulated in late harvested fruit at harvest as well as soft scald-affected fruit after storage. In contrast, early harvested fruit at harvest and disorder-free fruit after storage showed higher expression of transcripts associated with abiotic stress resistance, such as leucine-rich repeat receptor-like kinases, protein kinases with tetratricopeptide repeat domains, and auxin response factor, indicating a potential link between early maturity and enhanced cold tolerance in ‘Red Aroma’ apple fruit.
Authors
Melissa MagerøyAbstract
Showet får barna oppleve hvor fantastiske planter egentlig er! Vi utforsker skjulte fargene som finnes inne i plantene rundt oss, og lager magiske “rødkål regnbuer” som skifter farge rett foran øynene deres. Barna får se hvordan planter kan være fulle av overraskelser, hemmeligheter og fantastiske farger – akkurat som små natur-tryllekunstnere.
