biostudies-literatureAl-Hajaya YWellcome Trust1096-1108https://www.ebi.ac.uk/biostudies/studies/S-EPMC9305541biostudies-literatureUnknown45(4)Catalase is a well-known component of the cellular antioxidant network, but there have been conflicting conclusions reached regarding the nature of its peroxisome targeting signal. It has also been reported that catalase can be hijacked to the nucleus by effector proteins of plant pathogens. Using a physiologically relevant system where native untagged catalase variants are expressed in a cat2-1 mutant background, the C terminal most 18 amino acids could be deleted without affecting activity, peroxisomal targeting or ability to complement multiple phenotypes of the cat2-1 mutant. In contrast, converting the native C terminal tripeptide PSI to the canonical PTS1 sequence ARL resulted in lower catalase specific activity. Localisation experiments using split superfolder green fluorescent protPlant, cell & environmentNuclear and peroxisomal targeting of catalase.PMC9305541WT104918MAAl-Hajaya YKarpinska BFoyer CHBaker AfalseNuclear and peroxisomal targeting of catalase.Catalase is a well-known component of the cellular antioxidant network, but there have been conflicting conclusions reached regarding the nature of its peroxisome targeting signal. It has also been reported that catalase can be hijacked to the nucleus by effector proteins of plant pathogens. Using a physiologically relevant system where native untagged catalase variants are expressed in a cat2-1 mutant background, the C terminal most 18 amino acids could be deleted without affecting activity, peroxisomal targeting or ability to complement multiple phenotypes of the cat2-1 mutant. In contrast, converting the native C terminal tripeptide PSI to the canonical PTS1 sequence ARL resulted in lower catalase specific activity. Localisation experiments using split superfolder green fluorescent prot2022-01-01T00:00:00Z2022 Apr2026-05-09T18:20:49.839Z2022-08-06T14:53:06.438ZS-EPMC93055413504015810.1111/pce.14262