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SUPPRESSOR OF MAX2-LIKE 6, 7, and 8 (SMXL6,7,8) function as repressors and transcription factors of the strigolactone (SL) signaling pathway, playing an important role in the development and stress tolerance in Arabidopsis thaliana. However, the molecular mechanism by which SMXL6,7,8 negatively regulate drought tolerance and ABA response remains largely unexplored. In the present study, the interacting protein and downstream target genes of SMXL6,7,8 were investigated. Our results showed that the substrate receptor for the CUL4-based E3 ligase DDB1-BINDING WD-REPEAT DOMAIN (DWD) HYPERSENSITIVE TO ABA DEFICIENT 1 (ABA1) (DWA1) physically interacted with SMXL6,7,8. The degradation of SMXL6,7,8 proteins were partially dependent on DWA1. Disruption of SMXL6,7,8 resulted in increased drought tolerance and could restore the drought-sensitive phenotype of the dwa1 mutant. In addition, SMXL6,7,8 could directly bind to the promoter of SUCROSE NONFERMENTING 1 (SNF1)-RELATED PROTEIN KINASE 2.3 (SnRK2.3) to repress its transcription. The mutations in SnRK2.2/2.3 significantly suppressed the hypersensitivity of smxl6/7/8 to ABA-mediated inhibition of seed germination. Conclusively, SMXL6,7,8 interact with DWA1 to negatively regulate drought tolerance and target ABA-response genes. These data provide insights into drought tolerance and ABA response in Arabidopsis via the SMXL6,7,8-mediated SL signaling pathway.

Hydrogen sulfide (H2S), once recognized only as a poisonous gas, is now considered the third endogenous gaseous transmitter, along with nitric oxide (NO) and carbon monoxide (CO). Multiple lines of emerging evidence suggest that H2S plays positive roles in plant growth and development when at appropriate concentrations, including seed germination, root development, photosynthesis, stomatal movement, and organ abscission under both normal and stress conditions. H2S influences these processes by altering gene expression and enzyme activities, as well as regulating the contents of some secondary metabolites. In its regulatory roles, H2S always interacts with either plant hormones, other gasotransmitters, or ionic signals, such as abscisic acid (ABA), ethylene, auxin, CO, NO, and Ca2+. Remarkably, H2S also contributes to the post-translational modification of proteins to affect protein activities, structures, and sub-cellular localization. Here, we review the functions of H2S at different stages of plant development, focusing on the S-sulfhydration of proteins mediated by H2S and the crosstalk between H2S and other signaling molecules.

Background: Emergency and intensive care unit nurses are the main workforce fighting against COVID-19. Their professional identity may affect whether they can actively participate and be competent in care tasks during the pandemic., Objective: To examine the level of and changes in professional identity of Chinese emergency and intensive care unit nurses as the COVID-19 pandemic builds., Methods: A cross-sectional survey composed of the Professional Identity Scale for Nurses plus 2 open-ended questions was administered to Chinese emergency and intensive care unit nurses through an online questionnaire., Results: Emergency and intensive care unit nurses had a medium level of professional identity. Participants' total and item mean scores in 5 professional identity dimensions were higher than the professional identity norm established by Liu (P < .001). The greatest mean item score difference was in the dimension of professional identity evaluation (3.57 vs 2.88, P < .001). When asked about their feelings witnessing the COVID-19 situation and their feelings about participating in frontline work, 68.9% and 83.9%, respectively, reported positive changes in their professional identity., Conclusions: The professional identity of emergency and intensive care unit nurses greatly improved during the early stages of the COVID-19 pandemic. This finding may be attributed to more public attention and recognition of nurses' value, nurses' professional fulfillment, and nurses' feelings of being supported, motivated, respected, and valued., (© 2021 American Association of Critical-Care Nurses.)