Arabidopsis PAP17 is a dual-localized purple acid phosphatase up-regulated during phosphate deprivation, senescence, and oxidative stress
| Autor: | Emma J L Walker, Michal Pyc, Ang-Yu Liu, Gustavo C. MacIntosh, Robert T. Mullen, William C. Plaxton, Mina Ghahremani, Kyla A. Stigter, Bryden O'Gallagher |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
0106 biological sciences
Physiology Acid Phosphatase Mutant Arabidopsis Plant Science Vacuole 01 natural sciences Horseradish peroxidase Phosphates 03 medical and health sciences Gene Expression Regulation Plant Arabidopsis thaliana Glycoproteins Secretome 030304 developmental biology chemistry.chemical_classification 0303 health sciences Reactive oxygen species biology Arabidopsis Proteins Chemistry biology.organism_classification Plant Senescence Oxidative Stress Biochemistry biology.protein Intracellular 010606 plant biology & botany Peroxidase |
| Zdroj: | Journal of Experimental Botany. 73:382-399 |
| ISSN: | 1460-2431 0022-0957 |
| DOI: | 10.1093/jxb/erab409 |
| Popis: | A 35 kDa monomeric purple acid phosphatase (APase) was purified from cell wall extracts of Pi starved (–Pi) Arabidopsis thaliana suspension cells and identified as AtPAP17 (At3g17790) by mass spectrometry and N-terminal microsequencing. AtPAP17 was de novo synthesized and dual-localized to the secretome and/or intracellular fraction of –Pi or salt-stressed plants, or senescing leaves. Transiently expressed AtPAP17–green fluorescent protein localized to lytic vacuoles of the Arabidopsis suspension cells. No significant biochemical or phenotypical changes associated with AtPAP17 loss of function were observed in an atpap17 mutant during Pi deprivation, leaf senescence, or salinity stress. Nevertheless, AtPAP17 is hypothesized to contribute to Pi metabolism owing to its marked up-regulation during Pi starvation and leaf senescence, broad APase substrate selectivity and pH activity profile, and rapid repression and turnover following Pi resupply to –Pi plants. While AtPAP17 also catalyzed the peroxidation of luminol, which was optimal at pH 9.2, it exhibited a low Vmax and affinity for hydrogen peroxide relative to horseradish peroxidase. These results, coupled with absence of a phenotype in the salt-stressed or –Pi atpap17 mutant, do not support proposals that the peroxidase activity of AtPAP17 contributes to the detoxification of reactive oxygen species during stresses that trigger AtPAP17 up-regulation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|