OsPLS4 Is Involved in Cuticular Wax Biosynthesis and Affects Leaf Senescence in Rice

Abstract

Leaf senescence is one of the most common factors that affects the growth and yield of rice. Although numerous genes affecting leaf senescence have been identified, few involved in cuticular wax synthesis have been described for rice premature leaf senescence. Here, we cloned and characterized Premature Leaf Senescence 4 (PLS4) in rice (Oryza sativa), which encodes a putative 3-oxoacyl-reductase in the fatty acid biosynthetic pathway. Subcellular localization of OsPLS4 was observed in the chloroplast. A single nucleotide substitution in OsPLS4 reduced leaf cuticular wax, and the expression levels of most wax biosynthesis-associated genes were downregulated. TEM showed chloroplast development were defective in the pls4 mutant. Further investigation revealed that the chlorophyll (Chl) content was reduced in the pls4 mutant compared with the WT and that the photosynthesis rate was lower, which caused ROS dramatic accumulation at the heading stage. These results confirmed premature leaf senescence in pls4 plants. Cold treatment indicated that the mutant was more sensitive than the WT was to cold stress. Together, all the above results indicate that the OsPLS4 mutation affects cuticular wax biosynthesis and chloroplast development in rice, causing reduced cuticular wax and premature leaf senescence.

White Oak (Quercus Fabri Hance) Regenerated Stump Sprouts Show Few Symptom of Senescence During 40 Years’growth in the Natural Forest

“…Here, several antioxidative enzymes showed lowed activities in elder sprouts, but peroxidation products had not accumulated (Figure 1 and 2), that meant the 35-year age gap showed slightly in uence on antioxidative abilities both at the transcriptional and physiological levels, 40 years old regenerated sprouts still kept capacity to eliminate peroxidation products. This trend is different from senescent plant organs: antioxidative enzymes activities and ROS increased during Tulipa gesneriana petal senescence (Wang et al 2020); ROS increased but antioxidative enzymes activities decreased during rice leaf senescence (Zhou et al 2020).…”

White oak (Quercus fabri Hance) regenerated stump sprouts show few senescence symptoms during 40 years’ growth in a natural forest

“…This trend was different from in senescent plant organs. During Tulipa gesneriana petal senescence, antioxidative enzyme activity and ROS levels increase (Wang et al 2020), while, ROS levels increased but antioxidative enzyme activity levels decreased during rice leaf senescence (Zhou et al 2020).…”

White oak (Quercus fabri Hance) regenerated stump sprouts show few senescence symptoms during 40 years of growth in a natural forest

“…This trend was different from senescent plant organs. During Tulipa gesneriana petal senescence, antioxidative enzyme activity and ROS levels increase (Wang et al 2020), while, ROS levels increased but antioxidative enzyme activity levels decreased during rice leaf senescence (Zhou et al 2020).…”