Fig 2: Overexpression of miR-330-5p inhibited GLT-1 expression and BIT in vivo. A The expression of miR-330-5p in hippocampal CA1 subfield in rats after CIPC (n = 4). B Western blot illustrates the effect of miR-330-5p on the expression of GLT-1 protein after CIPC (n = 4). C, D Representative thionin staining photomicrographs show the effect of miR-330-5p on neuronal survival (C) (scale bar is 200 µm in (a) and 20 µm in (b–f)) and neuron density (D) at 7 days in CA1 hippocampus after global brain ischemia in rats (n = 5). E, F TUNEL staining photomicrographs (E) (scale bar = 20 µm) and the percent of positive cells (F) show the effect of miR-330-5p on neuronal apoptosis at 7 days after global brain ischemia in hippocampal CA1 subfield (n = 5). G The effect of miR-330-5p on the expressions of caspase-3 (n = 7) and Bax/Bcl-2 (n = 4) in rats during the induction of BIT by western blot. Data are presented as the mean ± SD. *P < 0.05, **P < 0.01

Fig 3: The hematoxylin and eosin (H&E) staining and the immunohistochemical (IHC) staining of phospho-ERK and cleaved caspase-3 in the tumor apoptotic area after different treatments (bar = 100 µm).

Fig 4: Proposed model for the regulation of innate immunity by DDX21 cleavage during virus infection. The double-edged-sword role of DDX21 in the regulation of innate immunity upon virus infection is depicted. At the early stage of infection, foreign RNA is recognized by DDX1 and recruits DDX21 and DHX36 to form a complex to mediate downstream antiviral innate immunity. At the late stage of infection, to avoid an excessive immune response, the host promotes DDX21 cleavage via caspase-3/6. Cleaved DDX21 tends to translocate from the nucleus to the cytoplasm. DDX21 cleavage reduces the interaction between upstream DDX1 and downstream TRIF and therefore suppresses signal transduction for a late counterregulatory effect to temper immune responses.

Fig 5: Preventing S-nitrosylation of ERK1 promotes ERK phosphorylation and cell survival, and suppresses apoptosis. Following transfection of U251 glioma cells with ERK1-Flag or ERK1 mutant form (ERKC183A), cells were treated with 500 µM GSNO for 24 h. (A and B) p-ERK1/2 was detected by western blotting and was semi-quantified. p-ERK1/2 levels were compared with ß-actin levels, and results were normalized to vector group. (C) Cell Counting kit-8 assay was performed to examine the viability of U251 glioma cells. Cell survival percentage was normalized to the vector group. (D and E) Caspase-3 protein expression was detected by western blotting and semi-quantified. Cleaved caspase-3 levels were compared with ß-actin levels, and results were normalized to the vector group. The lower panel of cleaved caspase-3 blot in part D was obtained after a longer exposure time compared with the upper panel. (F) Flow cytometric detection of apoptosis of U251 glioma cells. The percentage of apoptotic cells was quantified and compared. *P<0.05, **P<0.01 and ***P<0.001. IB, immunoblotting; ERK, extracellular signal-regulated kinase; fITC, fluorescein isothiocyanate; GSNO, S-nitrosoglutathione; p-ERK1/2, phosphorylated ERK1/2; PI, propidium iodide; WT, wild-type.