PR Proteins accumulate in the

PR Proteins accumulate in the Apoplast & vacuole.
Pathogenesis-related (PR) proteins are proteins produced in plants in the event of a pathogen attack.
These are structurally diverse groups of plant proteins that are toxic to invading fungal pathogens. They are widely distributed in plants in trace amounts but are produced in much greater concentrations following pathogen attack or stress.
Pathogenesis-related proteins are a class of proteins that accumulate in response to biotic and abiotic stresses to protect plants from damage in the apoplast and vacuole.