AAO2 impairment improves aldehyde detoxification by AAO3 in Arabidopsis leaves exposed to UVC or Rose Bengal

Zhadyrassyn Nurbekova, Sudhakar Srivastava, Zai Du Nja, Veronika Turečková, Miroslav Strand, Rustem T. Omarov, Moshe Sagi

2023

Full text Open access: Green Metadata (CSL-JSON)
DOI 10.1101/2023.09.22.559040
Data confidence 70 medium
How this score is calculated

It is built from checkable properties of the record itself: whether the article has a DOI, how many independent sources confirmed its data, whether the required fields are filled in, and how recent the latest confirmation is. Disagreement between sources and a missing identifier lower it. A value of 80 or above means the record was published without further checking; 60 to 79 means it is published at reduced confidence, with a manual check advisable. A record verified by an editor by hand is never pushed below 90 by a recalculation. This scores our data about the article, not the article itself.

Abstract

Abstract Among the three active aldehyde oxidases in Arabidopsis thaliana leaves (AAO1-3), AAO3, which catalyzes the oxidation of abscisic-aldehyde to abscisic-acid, was shown recently to function as a reactive aldehyde detoxifier. Notably, aao2KO mutants exhibited less senescence symptoms and lower aldehyde accumulation, such as acrolein, benzaldehyde, and HNE than in wild-type leaves exposed to UV-C or Rose-Bengal. The effect of the absence of AAO2 expression on aldehyde detoxification by AAO3 and/or AAO1 was studied by comparing the response of wild-type plants to the response of aao1Single mutant, aao2KO mutants and single mutants of aao3Ss . Notably, aao3Ss exhibited similar aldehyde accumulation and chlorophyll content to aao2KO treated with UV-C or Rose-Bengal. In contrast, wild-type and aao1S exhibited higher aldehyde accumulation that resulted in lower remaining chlorophyll than in aao 2KO leaves, indicating that the absence of active AAO2 enhanced AAO3 detoxification activity in aao2KO mutants. In support of this notion, employing abscisic-aldehyde as a specific substrate marker for AAO3 activity revealed enhanced AAO3 activity in aao2KO and aao3Ss leaves compared to wild-type treated with UV-C or Rose Bengal. The similar abscisic acid level accumulated in leaves of unstressed or stressed genotypes indicates that aldehyde detoxification by AAO3 is the cause for better stress resistance in aao2KO mutants. Employing the sulfuration process (known to activate aldehyde oxidases) in wild-type, aao2KO , and molybdenum-cofactor sulfurase ( aba3-1 ) mutant plants revealed that the active AAO2 in WT employs sulfuration processes essential for AAO3 activity level, resulting in the lower AAO3 activity in WT than AAO3 activity in aao2KO .