ABSTRACT
Auxin regulates plant growth and development through downstream signaling pathways, including the best-known SCFTIR1/AFB-Aux/IAA-ARF pathway and several other less characterized "noncanonical" pathways. Recently, one SCFTIR1/AFB-independent noncanonical pathway, mediated by Transmembrane Kinase 1 (TMK1), was discovered through the analyses of its functions in Arabidopsis apical hook development. Asymmetric accumulation of auxin on the concave side of the apical hook triggers DAR1-catalyzed release of the C-terminal of TMK1, which migrates into the nucleus, where it phosphorylates and stabilizes IAA32/34 to inhibit cell elongation, which is essential for full apical hook formation. However, the molecular factors mediating IAA32/34 degradation have not been identified. Here, we show that proteins in the CYTOKININ INDUCED ROOT WAVING 1 (CKRW1)/WAVY GROWTH 3 (WAV3) subfamily act as E3 ubiquitin ligases to target IAA32/34 for ubiquitination and degradation, which is inhibited by TMK1c-mediated phosphorylation. This antagonistic interaction between TMK1c and CKRW1/WAV3 subfamily E3 ubiquitin ligases regulates IAA32/34 levels to control differential cell elongation along opposite sides of the apical hook.
Subject(s)
Arabidopsis Proteins , Arabidopsis , F-Box Proteins , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Arabidopsis/metabolism , Indoleacetic Acids/metabolism , Signal Transduction , Ubiquitins/metabolism , Gene Expression Regulation, Plant , F-Box Proteins/genetics , F-Box Proteins/metabolismABSTRACT
@#Abstract: Objective To investigate the dynamic changes and clinical significance of specific antibodies in patients with coronavirus disease 2019 (COVID-19). Methods A retrospective study was conducted to collect 141 adult COVID-19 survivors who were followed up in the Eighth Hospital affiliated to Guangzhou Medical University from February 6, 2020, to March 24, 2021. The patients were divided into severe group (severe and critical) and non-severe group (light and ordinary) according to the diagnosis at discharge. The antibody changes of the two groups were compared and analyzed at 1 week, 2 weeks, 1 month, 3 months, 6 months and 1 year after discharge. Results After discharge from hospital, the positive rate of IgG in the severe group was 95.00% after 1 week and 100.00% in the following year, in the positive rate of IgG in the non-severe group was 59.50% after 1 week, 90.08% in 6 months and 76.03% in one year. The level of serum IgG in the severe group was significantly higher than that in non-severe group (Z=-2.441, P=0.015). One-year follow-up: the serum IgG in the severe group was significantly higher than that in the non-severe group (Z=-3.410, P=0.001). The serum IgM level of the severe group after one year follow-up was lower than that of the six months follow-up, the difference was statistically significant (Z=-2.259, P=0.024). The serum IgG and IgM level of the non-severe group after one year follow-up was lower than that of the six months follow-up, the difference was statistically significant (Z=-7.37, P<0.01; Z=3.850, P<0.01). Conclusion The level of serum protective antibody in COVID-19 patients remained high within 6 months after discharge, and remained stable within 1 year after discharge. The antibody titers in the severe group were significantly higher than those in the non-severe group and lasted for at least one year. COVID-19 survivors receive 1 year of natural immune protection, and patients with critical conditions receive immunity for longer periods of time.