The Schizophrenia-Related Protein Dysbindin-1A Is Degraded and Facilitates NF-Kappa B Activity in the Nucleus

<div><p>Dystrobrevin-binding protein 1 (<i>DTNBP1</i>), a gene encoding dysbindin-1, has been identified as a susceptibility gene for schizophrenia. Functioning with partners in synapses or the cytoplasm, this gene regulates neurite outgrowth and neurotransmitter release. Loss of dysbindin-1 affects schizophrenia pathology. Dysbindin-1 is also found in the nucleus, however, the characteristics of dysbindin in the nucleus are not fully understood. Here, we found that dysbindin-1A is degraded in the nucleus via the ubiquitin-proteasome system and that amino acids 2-41 at the N-terminus are required for this process. By interacting with p65, dysbindin-1A promotes the transcriptional activity of NF-kappa B in the nucleus and positively regulates MMP-9 expression. Taken together, the data obtained in this study demonstrate that dysbindin-1A protein levels are highly regulated in the nucleus and that dysbindin-1A regulates transcription factor NF-kappa B activity to promote the expression of MMP-9 and TNF-α.</p></div

Dysbindin-1A is degraded in the nucleus.

<p>(A) HEK293 cells that had been transfected with dysbindin-1A-EGFP were pre-treated with leptomycin B 20 ng/ml or equal volumes of ethanol for 1 hour, respectively. The cells were then treated with CHX for the indicated time, and cell extracts were subjected to immunoblot analysis. (B) The band intensity of dysbindin-1A-EGFP relative to GAPDH is shown. The values shown represent the means ± S.E. of three independent experiments. *, <i>P</i><0.05; **, <i>P</i><0.01; one-way ANOVA. (C) Subcellular localization of dysbindin-1A-EGFP and its variants that harbor a nuclear localization signal and/or a nuclear export signal mutant. HEK293 cells were transfected with the indicated plasmids, and the nuclei were stained with DAPI; The bar represents 10 μm. (D) The half-life of dysbindin-1A-NLS or the NES mutant was shorter than that of wild type dysbindin-1A. Dysbindin-1A-EGFP, dysbindin-1A-NLS-EGFP and dysbindin-1A-NES mutant-NLS-EGFP were transfected into HEK293 cells for 24 hours; the cells were then treated with CHX (100 μg/ml) for the indicated time. (E) The data from three independent experiments of (D) were quantified. The values shown represent means ± S.E. (F) The HEK293 cells were pre-treated with leptomycin B 20 ng/ml or equal volumes of ethanol for 1 hour, respectively. The cells were then treated with CHX for the indicated time, and cell extracts were subjected to immunoblot analysis. (G) The quantified analysis from three independent experiments of (F). The values shown represent the means ± S.E. *, <i>P</i><0.05; one-way ANOVA.</p

The N-terminal 2–41 amino acids of dysbindin-1A are important for its nuclear degradation.

<p>(A) The N-terminal sequence of dysbindin-1A (amino acids 1–42). The sequence was scored using Ubpred and BDM-PUB, and potential ubiquitination sites are colored red. (B) The potential dysbindin-1A ubiquitination site, lysine 21, was mutated to arginine. The ubiquitination of K21R and WT forms of dysbindin-1A was examined. (C) Dysbindin-1A-EGFP, EGFP-dysbindin (residues 1–189) or EGFP-dysbindin-1A residue 2–41 deletion mutant were co-transfected with HA-Ub into HEK293 cells, respectively. After culturing for 24 hours, 10 μM MG132 was added, and the cells were then cultured for an additional 12 hours. After lysis, the proteins were immunoprecipitated using an anti-GFP antibody and immunoblotted with an HA antibody. (D) The EGFP-dysbindin-1A residue 2–41 deletion mutant was more stable in the nucleus. HEK293 cells expressing dysbindin-1A-EGFP or EGFP-dysbindin-1A residue 2–41 deletion mutant were treated with leptomycin B (20 ng/ml) for 1 hour. The cells were then treated with CHX for the indicated time. Finally, cell extracts were subjected to immunoblot analysis. (E) The band intensity of the dysbindin-1A-EGFP and EGFP-dysbindin-1A residue 2–41 deletion mutant is shown, relative to GAPDH. The values shown represent the means ± S.E. of three independent experiments. *, <i>P</i><0.05; one-way ANOVA. (F) The localization of EGFP-dysbindin-1A del 2–41 under treatment of Ethanol or LMB. The nuclei were stained with DAPI; The bar represents 10 μm.</p

EGFP-NLS-dysbindin-1A del 2–41 is stable in nucleus.

<p>(A) The degradation of EGFP-dysbindin-1A del 2–41 or EGFP-NLS-dysbindin-1A del 2–41. (B) The quantitative analysis of (A). The values shown represent the means ± S.E. of three independent experiments. (C) The C-terminus of dysbindin-1A was not ubiquitinated in nucleus. The deletion mutants of dysbindin were transfected into cells. The ubiquitination of deletion mutants were examined.</p

Dysbindin-1A interacts with Rel A (p65) and promotes NF-kappa B activity.

<p>(A) A dual luciferase reporter assay shows that dysbindin-1A promotes NF-kappa B transcriptional activity. (B) Dysbindin-1A knockdown does not influence the protein levels of p65 in N2a cells. N2a cells were transfected with si-dys1# or si-dys2#. The resulting cell lysates were subjected to immunoblot analysis using antibodies to dysbindin-1A or p65. (C) p65 interacts with Flag-dysbindin-1A. In HEK293 cells that were co-transfected with Flag-dysbindin-1A and EGFP-p65, EGFP or EGFP-p65 was immunoprecipitated using an anti-GFP antibody. The immunoprecipitants were subjected to immunoblot analysis with the indicated antibodies. (D) Dysbindin-1A interacts with p65 in a GST-pulldown assay. (E) Endogenous dysbindin-1A interacts with endogenous p65 in SH-SY5Y cells. (F) EGFP-p65 interacts with Flag-dysbindin-1A in nucleus. The cytoplasm fraction or nuclear fraction of HEK293 cells transfected with EGFP/EGFP-p65 and Flag-dysbindin-1A were immunoprecipitated using an anti-GFP antibody. The immunoprecipitants were subjected to immunoblot analysis with the indicated antibodies. <i>IB</i>, immunoblot; <i>IP</i>, immunoprecipitation.</p

Dysbindin-1A is degraded via the ubiquitin-proteasome pathway in the nucleus.

<p>(A) Nuclear dysbindin-1A was degraded via the ubiquitin-proteasome pathway. Twenty-four hours after transfection with dysbindin-1A-EGFP, dysbindin-1A-NLS-EGFP and dysbindin-1A-NES mutant-NLS-EGFP, cells were treated with DMSO or MG132 (10 μM) for 12 hours, respectively. (B and C) Dysbindin-1A-NLS-EGFP and dysbindin-1A-NES mutant-NLS-EGFP were transfected into HEK293 cells for 24 hours. The cells were then treated with MG132 (10 μM) for 12 hours. Cell lysates were immunoprecipitated with GFP antibody and immunoblotted with ubiquitin antibody.</p

Insight of the State for Deliberately Introduced A‑Site Defect in Nanofibrous LaFeO₃ for Boosting Artificial Photosynthesis of CH₃OH

Perovskite-type LaFeO3 is regarded as a potentially efficient visible-light photocatalyst owing to its narrow bandgap energy and unique photovoltaic properties. However, the insufficient active sites and the unsatisfactory utilization of photogenerated carriers severely restrict the realistic application of pure LaFeO3. Herein, we fabricated a series of LaxFeO3−δ nanofibers (x = 1.0, 0.95, 0.9, 0.85, 0.8) with an A-site defect via sol–gel combined with the electrospinning technique. Wherein, the nonstoichiometric La0.9FeO3−δ possessed the highest CH3OH yield of 5.30 μmol·g–1·h–1 with good chemical stability. A series of advanced characterizations were applied to investigate the physicochemical properties and charge-carrier behaviors of the samples. The results illustrated that the one-dimensional (1D) nanostructures combined with the appropriate concentration of vacancy defects on the surface contributed to the radial migration of photogenerated carriers, inhibited the recombination of carriers, and provided more CO2 adsorption-activation sites. Furthermore, density functional theory (DFT) calculations were employed to reveal the influence mechanism of vacancy defects on LaFeO3. This work provides a strategy to enhance the performance of photocatalytic CO2 reduction by modulating the induced oxygen vacancies caused by the A-site defect in perovskite oxides

DataSheet_1_Identification of southern corn rust resistance QTNs in Chinese summer maize germplasm via multi-locus GWAS and post-GWAS analysis.zip

Southern corn rust (SCR) caused by Puccinia polysora Underw is a major disease leading to severe yield losses in China Summer Corn Belt. Using six multi-locus GWAS methods, we identified a set of SCR resistance QTNs from a diversity panel of 140 inbred lines collected from China Summer Corn Belt. Thirteen QTNs on chromosomes 1, 2, 4, 5, 6, and 8 were grouped into three types of allele effects and their associations with SCR phenotypes were verified by post-GWAS case-control sampling, allele/haplotype effect analysis. Relative resistance (RRR) and relative susceptibility (RRs) catering to its inbred carrier were estimated from single QTN and QTN-QTN combos and epistatitic effects were estimated for QTN-QTN combos. By transcriptomic annotation, a set of candidate genes were predicted to be involved in transcriptional regulation (S5_145, Zm00001d01613, transcription factor GTE4), phosphorylation (S8_123, Zm00001d010672, Pgk2- phosphoglycerate kinase 2), and temperature stress response (S6_164a/S6_164b, Zm00001d038806, hsp101, and S5_211, Zm00001d017978, cellulase25). The breeding implications of the above findings were discussed. </p

Giant second harmonic generation in supertwisted WS2 spirals grown in step edge particle induced non-Euclidean surfaces

In moir\'e crystals resulting from the stacking of twisted two-dimensional (2D) layered materials, a subtle adjustment in the twist angle surprisingly gives rise to a wide range of correlated optical and electrical properties. Herein, we report the synthesis of supertwisted WS2 spirals and the observation of giant second harmonic generation (SHG) in these spirals. Supertwisted WS2 spirals featuring different twist angles are synthesized on a Euclidean or step-edge particle-induced non-Euclidean surface using a carefully designed water-assisted chemical vapor deposition. We observed an oscillatory dependence of SHG intensity on layer number, attributed to atomically phase-matched nonlinear dipoles within layers of supertwisted spiral crystals where inversion symmetry is restored. Through an investigation into the twist angle evolution of SHG intensity, we discovered that the stacking model between layers plays a crucial role in determining the nonlinearity, and the SHG signals in supertwisted spirals exhibit enhancements by a factor of 2 to 136 when compared with the SHG of the single-layer structure. These findings provide an efficient method for the rational growth of 2D twisted structures and the implementation of twist angle adjustable endowing them great potential for exploring strong coupling correlation physics and applications in the field of twistronics