A Stress-Associated Protein, , From Provides Tolerance to Salt Stress.

The growth and production of poplars are usually affected by unfavorable environmental conditions such as soil salinization. Thus, enhancing salt tolerance of poplars will promote their better adaptation to environmental stresses and improve their biomass production. Stress-associated proteins (SAPs) are a novel class of A20/AN1 zinc finger proteins that have been shown to confer plants' tolerance to multiple abiotic stresses. However, the precise functions of genes in poplars are still largely unknown. Here, the expression profiles of in response to salt stress revealed that with two AN1 domains was up-regulated dramatically during salt treatment. The β-glucuronidase (GUS) staining showed that was accumulated dominantly in leaf and root, and the GUS signal was increased under salt condition. The transgenic plants overexpressing exhibited higher seed germination and better growth than wild-type (WT) plants under salt stress, demonstrating that overexpression of increased salt tolerance. Higher activities of antioxidant enzymes were found in -overexpressing plants than in WT plants under salt stress. Transcriptome analysis revealed that some stress-related genes, including , , , , , and , were induced by salt in transgenic plants. Moreover, the pathways of flavonoid biosynthesis and metabolic processes, regulation of response to stress, response to ethylene, dioxygenase activity, glucosyltransferase activity, monooxygenase activity, and oxidoreductase activity were specially enriched in transgenic plants under salt condition. Taken together, our results demonstrate that enhances salt tolerance through up-regulating the expression of stress-related genes and mediating multiple biological pathways.