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The auxin/indoleacetic acid (Aux/IAA) family plays a central role in regulating gene expression during auxin signal transduction. Nonetheless, there is limited knowledge regarding this gene family in sugarcane. In this study, 92 members of the IAA family were identified in Saccharum spontaneum, distributed on 32 chromosomes, and classified into three clusters based on phylogeny and motif compositions. Segmental duplication and recombination events contributed largely to the expansion of this superfamily. Additionally, cis-acting elements in the promoters of SsIAAs involved in plant hormone regulation and stress responsiveness were predicted. Transcriptomics data revealed that most SsIAA expressions were significantly higher in stems and basal parts of leaves, and at nighttime, suggesting that these genes might be involved in sugar transport. QRT-PCR assays confirmed that cold and salt stress significantly induced four and five SsIAAs, respectively. GFP-subcellular localization showed that SsIAA23 and SsIAA12a were localized in the nucleus, consistent with the results of bioinformatics analysis. In conclusion, to a certain extent, the functional redundancy of family members caused by the expansion of the sugarcane IAA gene family is related to stress resistance and regeneration of sugarcane as a perennial crop. This study reveals the gene evolution and function of the SsIAA gene family in sugarcane, laying the foundation for further research on its mode of action. [ABSTRACT FROM AUTHOR]

Oxygen vacancy (V O ) has been recognized to possess an effect to promote the charge separation and transfer (CST) in various n-type semiconductor based photoelectrodes. But how external stimulus will change this V O effect has not been investigated. In this work, external polarization is applied to investigate the effect of V O on the CST process of a typical ferroelectric BiFeO 3 photoelectrode. It is found that negative poling treatment can significantly boost V O effect, while positive poling treatment will deteriorate the CST capability in BiFeO 3 photoelectrodes. This poling history determined V O effect is rooted in the V O induced defect dipoles, wherein their alignment produces a depolarization electric field to modulate the CST driving force. This finding highlights the significance of poling history in functionalizing the V O in a photoelectrode., (© 2024 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

Aging is a critical risk factor for unfavorable clinical outcomes among COVID-19 patients and may impact vaccine efficacy. However, whether the senescence of T cells is associated with severe COVID-19 outcome in elderly individuals is unclear. Using flow cytometry, we analyzed the frequency of senescent T cells (Tsens) in peripheral blood from 100 hospitalized elderly COVID-19 patients and compared differences between those with mild/moderate and severe/critical illness. We also assessed correlations between the percentage of Tsens and the quantity and quality of spike-specific antibodies by ELISA, neutralizing antibody test kit, and ELISPOT assay respectively, the cytokine production profile of COVID-19 reactive T cells, and plasma soluble factors by cytometric bead array (CBA). Our study found a significantly elevated level of CD4 + Tsens in patients with severe/critical disease compared to those with mild/moderate illness. Patients with a higher level of CD4 + Tsens (>19.78%) showed a decreased survival rate compared to those with a lower level (≤19.78%). This is more pronounced among patients with breakthrough infections. The percentage of CD4 + Tsens was negatively correlated with spike-specific antibody titers, neutralization ability, and COVID-19 reactive IL-2 + CD4 + T cells. In addition, spike-specific antibody levels were positively correlated with IL-2 producing T cells and plasma IL-2 amount. Mechanistically, with defective CD40L, T cells from patients with CD4 + Tsens >19.78% were unable to support B cell proliferation and differentiation. Our data demonstrate that the percentage of CD4 + Tsens in peripheral blood may serve as a reliable biomarker for the prognosis of severe COVID-19 patients, especially in breakthrough infections. Therefore, restoring the immune response of CD4 + Tsens may be key to preventing severe illness and improving vaccine efficacy in older adults.