Senescence-associated receptor-like kinase (AtSARK) involved in salt induced senescence

Salinity is one of the main factors that negatively influence growth of crop plants and productivity of agricultural sector worldwide. As other stresses, salinity may induce premature senescence in different plant species. Plant senescence is a complex process that is regulated by various genetic mechanisms at several levels. Previously, it was observed that senescence-associated receptor-like kinase (SARK) positively regulates natural leaf senescence in Soybean and Arabidopsis plant, however its involvement in stress induced senescence has not been shown. Here, the wild type (WT) of Arabidopsis thaliana model plant and homozygous Atsark mutant were investigated under salinity stress. The phenotypic analysis of senescence symptoms, Reactive Oxygen Species (ROS) level, Ascorbate Peroxidase (APER) and Catalase (CAT) activity were evaluated after salinity stress. Atsark mutant showed less damage and delayed senescence symptom compared to WT. WT showed higher disbalance in ROS level and lower enhancement of APER and CAT activity compared to Atsark mutant. Thus, the AtSARK seems to be involved in induction of premature senescence induced by salinity stress.
Keywords: Arabidopsis; induced senescence; Senescence-associated receptor-like kinase; salinity; ROS; catalase (CAT); ascorbic peroxidase (APER).