Hollow manganese dioxide-chitosan hydrogel for the treatment of atopic dermatitis through inflammation-suppression and ROS scavenging.

Atopic dermatitis (AD) is a chronic inflammatory disease associated with immune dysfunction. High levels of reactive oxygen species (ROS) can lead to oxidative stress, release of pro-inflammatory cytokines, and T-cell differentiation, thereby promoting the onset and worsening of AD. In this study, we innovatively used quaternary ammonium chitosan (QCS) and tannic acid (TA) as raw materials to design and prepare a therapeutic hydrogel(H-MnO2-Gel) loaded with hollow manganese dioxide nanoparticles (H-MnO2 NPs). In this system, the hydrogel is mainly cross-linked by dynamic ion and hydrogen bonding between QCS and TA, resulting in excellent moisture retention properties. Moreover, due to the inherent antioxidant properties of QCS/TA, as well as the outstanding H2O2 scavenging ability of H-MnO2 NPs, the hydrogel exhibits significant ROS scavenging capability. In vitro experiments have shown that H-MnO2-Gel exhibits good cellular biocompatibility. Importantly, in an AD-induced mouse model, H-MnO2-Gel significantly enhanced therapeutic effects by reducing epidermal thickness, mast cell number, and IgE antibodies. These findings suggest that H-MnO2-Gel, by effectively clearing ROS and regulating the inflammatory microenvironment, provides a promising approach for the treatment of AD.

Genomic estimates of mutation and substitution rates contradict the evolutionary speed hypothesis of the latitudinal diversity gradient.

The latitudinal diversity gradient (LDG) refers to a decrease in biodiversity from the equator to the poles. The evolutionary speed hypothesis, backed by the metabolic theory of ecology, asserts that nucleotide mutation and substitution rates per site per year are higher and thereby speciation rates are higher at higher temperatures, generating the LDG. However, prior empirical investigations of the relationship between the temperature and mutation or substitution rate were based on a few genes and the results were mixed. We here revisit this relationship using genomic data. No significant correlation between the temperature and mutation rate is found in 13 prokaryotes or in 107 eukaryotes. An analysis of 234 diverse trios of bacterial taxa indicates that the synonymous substitution rate is not significantly associated with the growth temperature. The same data, however, reveal a significant negative association between the nonsynonymous substitution rate and temperature, which is explainable by a larger fraction of detrimental nonsynonymous mutations at higher temperatures due to a stronger demand for protein stability. We conclude that the evolutionary speed hypothesis of the LDG is unsupported by genomic data and advise that future mechanistic studies of the LDG should focus on other hypotheses.

Identification of Biomarkers Associated with Heart Failure Caused by Idiopathic Dilated Cardiomyopathy Using WGCNA and Machine Learning Algorithms.

Background: The genetic factors and pathogenesis of idiopathic dilated cardiomyopathy-induced heart failure (IDCM-HF) have not been understood thoroughly; there is a lack of specific diagnostic markers and treatment methods for the disease. Hence, we aimed to identify the mechanisms of action at the molecular level and potential molecular markers for this disease. Methods: Gene expression profiles of IDCM-HF and non-heart failure (NF) specimens were acquired from the database of Gene Expression Omnibus (GEO). We then identified the differentially expressed genes (DEGs) and analyzed their functions and related pathways by using "Metascape". Weighted gene co-expression network analysis (WGCNA) was utilized to search for key module genes. Candidate genes were identified by intersecting the key module genes identified via WGCNA with DEGs and further screened via the support vector machine-recursive feature elimination (SVM-RFE) method and the least absolute shrinkage and selection operator (LASSO) algorithm. At last, the biomarkers were validated and evaluated the diagnostic efficacy by the area under curve (AUC) value and further confirmed the differential expression in the IDCM-HF and NF groups using an external database. Results: We detected 490 genes exhibiting differential expression between IDCM-HF and NF specimens from the GSE57338 dataset, with most of them being concentrated in the extracellular matrix (ECM) of cells related to biological processes and pathways. After screening, 13 candidate genes were identified. Aquaporin 3 (AQP3) and cytochrome P450 2J2 (CYP2J2) showed high diagnostic efficacy in the GSE57338 and GSE6406 datasets, respectively. In comparison to the NF group, AQP3 was significantly down-regulated in the IDCM-HF group, while CYP2J2 was significantly up-regulated. Conclusion: As far as we know, this is the first study that combines WGCNA and machine learning algorithms to screen for potential biomarkers of IDCM-HF. Our findings suggest that AQP3 and CYP2J2 could be used as novel diagnostic markers and treatment targets of IDCM-HF.

Iodine values, peroxide values and acid values of Bohai algae oil compared with other oils during the cooking.

Objective: Bohai algae oil contains polyunsaturated fatty acids, such as EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), which are the very important polyunsaturated fatty acids for the human body. In Traditional Chinese Cooking, all cooking methods cannot do without oils. However, the heat of cooking may always lead to formation of large amounts of decomposition products that affect the sensory, nutritional and functional quality of the oils to be unhealthy and the products being cooked, especially the food or edible oil rich in polyunsaturated fatty acids. Therefore, the objective of this study was to research the effect and change of heating on the quality characteristics of Bohai algae oil comparison with soybean oil and olive oil. Method: Quality characteristics such as the iodine values (IVs), peroxide values (POVs) and acid values (AVs) of Bohai algae oil, soybean oil and olive oil were measured, cooking conditions as factors of the study. Result: The POVs percentage changes of Bohai algae oil were larger than the IVs and AVs percentage changes. Bohai algae oil was better heated in a microwave oven at microwave P-20 within 3min, microwave P-60 and P-H1 within 2min, or in induction cooker at 1500w within 1min, or on electric stove (direct heated) within 2min. Conclusion: Bohai algae oil was suitable used for low-temperature and short-time cooking or for salad. This study has important significance for promoting the commercial value and extensive application of Bohai algae oil in daily cooking. It plays a theoretical significance role in Bohai algae oil's better processing and traditional chinese cooking. It can improve product quality to further expand the food processing research scope of Bohai algae oil and increase the richness, diversity and universality of edible methods of Bohai algae oil.

Cinobufacini suppresses malignant behaviors of endometrial cancer by regulating NF-κB pathway.

Cinobufagin has inhibitory effects on various tumors, but there are few studies on gynecological tumors. This study explored the function and molecular mechanism of cinobufagin in endometrial cancer (EC). Different concentrations of cinobufagin treated EC cells (Ishikawa and HEC-1). Clone formation, methyl thiazolyl tetrazolium (MTT), flow cytometry, and transwell assays were used to detect malignant behaviors. A Western blot assay was performed to detect protein expression. Cinobufacini was sensitive to the inhibition of EC cell proliferation in a time- and concentration-dependent manner. Meanwhile, EC cell apoptosis was induced by cinobufacini. In addition, cinobufacini impaired the invasive and migratory abilities of EC cells. More importantly, cinobufacini blocked the nuclear factor kappa beta (NF-κB) pathway in EC by inhibiting p-IkBα and p-p65 expression. Cinobufacini suppresses malignant behaviors of EC by blocking the NF-κB pathway.

MiR-140 is involved in T-2 toxin-induced matrix degradation of articular cartilage.

T-2 toxin is one of the most toxic mycotoxins contaminating various grains. It is considered an environmental risk factor for Kashin-Beck disease (KBD), an endemic degenerative osteochondrosis. Currently, the underlying molecular mechanisms of articular cartilage damage caused by T-2 toxin have not been elucidated. Studies have shown that miR-140 is essential for cartilage formation, and extracellular matrix (EMC) synthesis and degradation. The objective of this study was to investigate the mechanism of miR-140 involvement in T-2 toxin-induced articular cartilage damage. Two treatment groups, each containing wild-type mice and miR-140 knockout mice were administered with T-2 toxin (200 ng/g BW/day) or a normal diet for 1 month, 3 months, and 6 months. Results showed that T-2 toxin caused articular cartilage and growth plate damage in mice. The expression of miR-140 decreased in articular cartilage of wild-type mice treated with T-2 toxin, and miR-140 deficiency aggravated T-2 toxin-induced knee cartilage damage. T-2 toxin-caused the reduction of miR-140 expression was consistent with collagen type II (COL2A1), aggrecan (ACAN), and SRY-box containing gene 9 (SOX9) and opposite to matrix metalloproteinase 13 (MMP13), a disintegrin and metalloproteinase with thrombospondin motif 5 (ADAMTS-5), and v-ral simian leukemia viral oncogene homolog A (RALA). In addition, we collected finger joints cartilage and knee joints cartilage from KBD patients and controls for paraffin embedding and sectioning. Results found that the expression of miR-140 in the articular cartilage of the KBD group was lower than that of the control group. The expression of COL2A1, ACAN, and SOX9 decreased, whereas ADAMTS-5, MMP13, and RALA increased in the articular cartilage of the KBD group. These results revealed that miR-140 might be involved in T-2 toxin-induced degradation of the ECM of articular cartilage. Moreover, the occurrence of KBD might be related to the decreased expression of miR-140 in articular cartilage.

Protection of the human gene research literature from contract cheating organizations known as research paper mills.

Human gene research generates new biology insights with translational potential, yet few studies have considered the health of the human gene literature. The accessibility of human genes for targeted research, combined with unreasonable publication pressures and recent developments in scholarly publishing, may have created a market for low-quality or fraudulent human gene research articles, including articles produced by contract cheating organizations known as paper mills. This review summarises the evidence that paper mills contribute to the human gene research literature at scale and outlines why targeted gene research may be particularly vulnerable to systematic research fraud. To raise awareness of targeted gene research from paper mills, we highlight features of problematic manuscripts and publications that can be detected by gene researchers and/or journal staff. As improved awareness and detection could drive the further evolution of paper mill-supported publications, we also propose changes to academic publishing to more effectively deter and correct problematic publications at scale. In summary, the threat of paper mill-supported gene research highlights the need for all researchers to approach the literature with a more critical mindset, and demand publications that are underpinned by plausible research justifications, rigorous experiments and fully transparent reporting.

Preferred synonymous codons are translated more accurately: Proteomic evidence, among-species variation, and mechanistic basis.

A commonly stated cause of unequal uses of synonymous codons is their differential translational accuracies. A key prediction of this long-standing translational accuracy hypothesis (TAH) of codon usage bias is higher translational accuracies of more frequently used synonymous codons, which, however, has had no direct evidence beyond case studies. Analyzing proteomic data from Escherichia coli, we present direct, global evidence for this prediction. The experimentally measured codon-specific translational accuracies validate a sequence-based proxy; this proxy provides support for the TAH from the vast majority of over 1000 taxa surveyed in all domains of life. We find that the relative translational accuracies of synonymous codons vary substantially among taxa and are strongly correlated with the amounts of cognate transfer RNAs (tRNAs) relative to those of near-cognate tRNAs. These and other observations suggest a model in which selections for translational efficiency and accuracy drive codon usage bias and its coevolution with the tRNA pool.

An IFI6-based hydrogel promotes the healing of radiation-induced skin injury through regulation of the HSF1 activity.

Radiation-induced skin injury (RISI) is a common complication of radiotherapy. Interferon-alpha inducible protein 6 (IFI6) significantly reduces the radiation sensitivity of HaCaT cells. Sodium alginate (SA) has substantial moisturizing properties. Graphene oxide (GO) is a suitable substrate with physical antibacterial properties. Therefore, we designed materials to modify IFI6 using the biogule of polydopamine (PDA) connected to GO/SA. The structure, size, morphology, and elemental compositions of IFI6-PDA@GO/SA were analyzed. Cytological studies suggested that IFI6-PDA@GO/SA is non-toxic to HaCaT cells, with antibacterial properties. It promotes migration and vascularization and inhibits apoptosis. These cells express IFI6 after irradiation. The mouse model suggested that IFI6-PDA@GO/SA promotes wound healing and reduces reactive oxygen species expression. IFI6-PDA@GO/SA accelerates RISI healing, possibly by initiating the SSBP1/HSF1 signaling pathway. In addition, IFI6-PDA@GO/SA improves the immune microenvironment. This study constitutes the first use of IFI6 as a RISI wound-healing material.

Comparison of Clinical Outcomes Between Ticagrelor and Clopidogrel in Acute Coronary Syndrome: A Comprehensive Meta-Analysis.

BACKGROUND: Ticagrelor is currently recommended for patients with the acute coronary syndrome (ACS). However, recent studies have yielded controversial results. OBJECTIVE: To compare the clinical outcomes between ticagrelor and clopidogrel in patients with ACS. METHODS: Three electronic databases were queried until April 25, 2021. We defined major adverse cardiovascular events (MACEs) as the primary efficacy endpoint. The secondary efficacy endpoints included stroke, stent thrombosis, cardiovascular death, all-cause death, and myocardial infarction. The safety endpoints were (major and minor) bleeding. Odds ratios (ORs) and 95% CIs were calculated to represent the estimated effect sizes. RESULTS: A total of 270,937 patients with ACS from 10 clinical trials and 18 observational studies were included. No significant difference was detected in MACE (OR 0.81, 95% CI 0.60-1.08, p = 0.15, I 2 = 64.83%). However, ticagrelor introduced a higher risk of bleeding (1.46, 1.17-1.83, 0.00, 61.66%) and minor bleeding (1.71, 1.33-2.21, 0.00, 4.65%) in clinical trials. The results of secondary efficacy endpoints differed in the clinical trials and observational studies. Subgroup analysis demonstrated that ticagrelor showed better therapeutic effects in patients who underwent the percutaneous coronary intervention (PCI) (0.38, 0.23-0.63, 0.00, 0) than those intended for PCI (1.03, 0.76-1.38, 0.87, 64.26%). Meanwhile, ticagrelor showed different therapeutic effects on patients with ACS of different ethnicities and different countries. CONCLUSION: This meta-analysis demonstrated that ticagrelor is not superior to clopidogrel in MACE but is associated with a higher risk of bleeding in patients with ACS. Different PCI strategies, ethnicities, and countries may be the factors that contribute to different therapeutic effects of ticagrelor. SYSTEMATIC REVIEW REGISTRATION: This study is registered with PROSPERO (CRD42021251212).

Rampant False Detection of Adaptive Phenotypic Optimization by ParTI-Based Pareto Front Inference.

Organisms face tradeoffs in performing multiple tasks. Identifying the optimal phenotypes maximizing the organismal fitness (or Pareto front) and inferring the relevant tasks allow testing phenotypic adaptations and help delineate evolutionary constraints, tradeoffs, and critical fitness components, so are of broad interest. It has been proposed that Pareto fronts can be identified from high-dimensional phenotypic data, including molecular phenotypes such as gene expression levels, by fitting polytopes (lines, triangles, tetrahedrons, and so on), and a program named ParTI was recently introduced for this purpose. ParTI has identified Pareto fronts and inferred phenotypes best for individual tasks (or archetypes) from numerous data sets such as the beak morphologies of Darwin's finches and mRNA concentrations in human tumors, implying evolutionary optimizations of the involved traits. Nevertheless, the reliabilities of these findings are unknown. Using real and simulated data that lack evolutionary optimization, we here report extremely high false-positive rates of ParTI. The errors arise from phylogenetic relationships or population structures of the organisms analyzed and the flexibility of data analysis in ParTI that is equivalent to p-hacking. Because these problems are virtually universal, our findings cast doubt on almost all ParTI-based results and suggest that reliably identifying Pareto fronts and archetypes from high-dimensional phenotypic data are currently generally difficult.

Allele-specific single-cell RNA sequencing reveals different architectures of intrinsic and extrinsic gene expression noises.

Gene expression noise refers to the variation of the expression level of a gene among isogenic cells in the same environment, and has two sources: extrinsic noise arising from the disparity of the cell state and intrinsic noise arising from the stochastic process of gene expression in the same cell state. Due to the low throughput of the existing method for measuring the two noise components, the architectures of intrinsic and extrinsic expression noises remain elusive. Using allele-specific single-cell RNA sequencing, we here estimate the two noise components of 3975 genes in mouse fibroblast cells. Our analyses verify predicted influences of several factors such as the TATA-box and microRNA targeting on intrinsic or extrinsic noises and reveal gene function-associated noise trends implicating the action of natural selection. These findings unravel differential regulations, optimizations, and biological consequences of intrinsic and extrinsic noises and can aid the construction of desired synthetic circuits.

NACHT, LRR, and PYD domains-containing Protein 3 and LL-37: prognostic value of new biomarkers in community-acquired pneumonia. / Proteína 3 contendo um domínio NACHT, porção C-terminal rica em repetições de leucina e de domínio pirina e LL-37: valor prognóstico de novos biomarcadores em pneumonia adquirida na comunidade.

OBJECTIVE: This study aimed to determine the serum levels of NACHT, Leucine-rich repeat (LRR), and Pyrin (PYD) domains-containing Protein 3 (NLRP3) and cathelicidin LL-37, and investigate their prognostic significance in community-acquired pneumonia (CAP). METHODS: The sample of this prospective study was composed of 76 consecutive patients with CAP. Demographic data and clinical characteristics were collected. Serum levels of NLRP3 and LL-37 were determined by ELISA. Spearman's analysis was used to evaluate the correlation between NLRP3 and LL-37. Association of NLRP3 and LL-37 with 30-day survival and mortality rates was assessed using the Kaplan-Meier curve and logistic regression analysis. RESULTS: Serum NLRP3 significantly increased whereas serum LL-37 significantly decreased in patients with severe CAP. Significant correlation was observed between serum NLRP3 and LL-37 in CAP patients. Patients with higher levels of NLRP3 and lower levels of LL-37 showed lower 30-day survival rate and higher mortality compared with those with lower NLRP3 and higher LL-37 levels. CONCLUSION: Severe CAP patients tend to present higher serum NLRP3 and lower serum LL-37, which might serve as potential biomarkers for CAP prognosis.

OBJETIVO: Este estudo teve como objetivo determinar os níveis séricos de proteína 3 contendo um domínio NACHT, porção C-terminal rica em repetições de leucina e de domínio pirina (NLRP3) e catelicidina LL-37, bem como investigar sua importância prognóstica em pneumonia adquirida na comunidade (PAC). MÉTODOS: Este estudo prospectivo incluiu 76 pacientes com PAC. Foram obtidos dados demográficos e características clínicas. Os níveis séricos de NLRP3 e LL-37 foram determinados por meio do teste ELISA. A correlação entre NLRP3 e LL-37 foi estimada por intermédio da análise de Spearman. A associação entre NLRP3 e LL-37 com 30 dias de taxa de sobrevida e de mortalidade foi avaliada pela curva de Kaplan-Meier e análise de regressão logística. RESULTADOS: Os níveis séricos de NLRP3 estavam elevados, enquanto os níveis de LL-37 apresentaram redução significativa em pacientes com PAC grave. Observou-se correlação significativa entre os níveis séricos de NLRP3 e LL-37 em pacientes com PAC. Pacientes com níveis elevados de NLRP3 e níveis reduzidos de LL-37 exibiram maior taxa de sobrevida em 30 dias e de mortalidade quando comparados com aqueles com níveis inferiores de NLRP3 e LL-37. CONCLUSÕES: Pacientes com PAC grave tendem a apresentar níveis séricos elevados de NLRP3 e níveis reduzidos de LL-37, o que pode ser utilizado como um potencial biomarcador prognóstico.

Chromosome-wide co-fluctuation of stochastic gene expression in mammalian cells.

Gene expression is subject to stochastic noise, but to what extent and by which means such stochastic variations are coordinated among different genes are unclear. We hypothesize that neighboring genes on the same chromosome co-fluctuate in expression because of their common chromatin dynamics, and verify it at the genomic scale using allele-specific single-cell RNA-sequencing data of mouse cells. Unexpectedly, the co-fluctuation extends to genes that are over 60 million bases apart. We provide evidence that this long-range effect arises in part from chromatin co-accessibilities of linked loci attributable to three-dimensional proximity, which is much closer intra-chromosomally than inter-chromosomally. We further show that genes encoding components of the same protein complex tend to be chromosomally linked, likely resulting from natural selection for intracellular among-component dosage balance. These findings have implications for both the evolution of genome organization and optimal design of synthetic genomes in the face of gene expression noise.

Proteína 3 contendo um domínio NACHT, porção C-terminal rica em repetições de leucina e de domínio pirina e LL-37: valor prognóstico de novos biomarcadores em pneumonia adquirida na comunidade / NACHT, LRR, and PYD domains-containing Protein 3 and LL-37: prognostic value of new biomarkers in community-acquired pneumonia

RESUMO Objetivo Este estudo teve como objetivo determinar os níveis séricos de proteína 3 contendo um domínio NACHT, porção C-terminal rica em repetições de leucina e de domínio pirina (NLRP3) e catelicidina LL-37, bem como investigar sua importância prognóstica em pneumonia adquirida na comunidade (PAC). Métodos Este estudo prospectivo incluiu 76 pacientes com PAC. Foram obtidos dados demográficos e características clínicas. Os níveis séricos de NLRP3 e LL-37 foram determinados por meio do teste ELISA. A correlação entre NLRP3 e LL-37 foi estimada por intermédio da análise de Spearman. A associação entre NLRP3 e LL-37 com 30 dias de taxa de sobrevida e de mortalidade foi avaliada pela curva de Kaplan-Meier e análise de regressão logística. Resultados Os níveis séricos de NLRP3 estavam elevados, enquanto os níveis de LL-37 apresentaram redução significativa em pacientes com PAC grave. Observou-se correlação significativa entre os níveis séricos de NLRP3 e LL-37 em pacientes com PAC. Pacientes com níveis elevados de NLRP3 e níveis reduzidos de LL-37 exibiram maior taxa de sobrevida em 30 dias e de mortalidade quando comparados com aqueles com níveis inferiores de NLRP3 e LL-37. Conclusões Pacientes com PAC grave tendem a apresentar níveis séricos elevados de NLRP3 e níveis reduzidos de LL-37, o que pode ser utilizado como um potencial biomarcador prognóstico.

ABSTRACT Objective This study aimed to determine the serum levels of NACHT, Leucine-rich repeat (LRR), and Pyrin (PYD) domains-containing Protein 3 (NLRP3) and cathelicidin LL-37, and investigate their prognostic significance in community-acquired pneumonia (CAP). Methods The sample of this prospective study was composed of 76 consecutive patients with CAP. Demographic data and clinical characteristics were collected. Serum levels of NLRP3 and LL-37 were determined by ELISA. Spearman's analysis was used to evaluate the correlation between NLRP3 and LL-37. Association of NLRP3 and LL-37 with 30-day survival and mortality rates was assessed using the Kaplan-Meier curve and logistic regression analysis. Results Serum NLRP3 significantly increased whereas serum LL-37 significantly decreased in patients with severe CAP. Significant correlation was observed between serum NLRP3 and LL-37 in CAP patients. Patients with higher levels of NLRP3 and lower levels of LL-37 showed lower 30-day survival rate and higher mortality compared with those with lower NLRP3 and higher LL-37 levels. Conclusion Severe CAP patients tend to present higher serum NLRP3 and lower serum LL-37, which might serve as potential biomarkers for CAP prognosis.

Inhibition of PirB Activity by TAT-PEP Improves Mouse Motor Ability and Cognitive Behavior.

Paired immunoglobulin-like receptor B (PirB), a functional receptor for myelin-associated inhibitory proteins, plays an important role in axon regeneration in injured brains. However, its role in normal brain function with age has not been previously investigated. Therefore in this study, we examined the expression level of PirB in the cerebral cortex, hippocampus and cerebellum of mice at 1 month, 3 months and 18 months of age. The results showed that the expression of PirB increased with age. We further demonstrated that overexpression of PirB inhibited neurite outgrowth in PC12 cells, and this inhibitory activity of PirB could be reversed by TAT-PEP, which is a recombinant soluble PirB ectodomain fused with TAT domain for blood-brain barrier penetration. In vivo study, intraperitoneal administration of TAT-PEP was capable of enhancing motor capacity and spatial learning and memory in mice, which appeared to be mediated through regulation of brain-derived neurotrophic factor (BDNF) secretion. Our study suggests that PirB is associated with aging and TAT-PEP may be a promising therapeutic agent for modulation of age-related motor and cognitive dysfunctions.

Cell-penetrable mouse forkhead box protein 3 alleviates experimental arthritis in mice by up-regulating regulatory T cells.

Regulatory T cells (T(regs)) have potential applications in clinical disease therapy, such as autoimmune diseases and transplant rejection. However, their numbers are limited. Forkhead box protein 3 (FoxP3) is a key transcription factor that controls T(reg) development and function. Here, we generated a cell-permeable fusion protein, protein transduction domain (PTD)-conjugated mouse FoxP3 protein (PTD-mFoxP3), and evaluated whether PTD-mFoxp3 can alleviate rheumatoid arthritis (RA) in the collagen-induced arthritis (CIA) mouse model. As expected, PTD-mFoxP3 was transduced into cells effectively, and inhibited T cell activation and attenuated the cell proliferation. It decreased interleukin (IL) 2 and interferon (IFN)-γ expression, and increased IL-10 expression in activated CD4(+)CD25(-) T cells. PTD-mFoxP3-transduced CD4(+)CD25(-) T cells attenuated proliferation of activated CD4(+)CD25(-) T cells. In addition, PTD-mFoxP3 blocked the Th17 differentiation programme in vitro and down-regulated IL-17 production from T cells by modulating induction and levels of retinoid-related orphan receptor gamma t (RORγt). Intra-articular delivery of PTD-mFoxP3 delayed disease incidence remarkably and alleviated autoimmune symptoms of CIA mice. Moreover, protective effects of PTD-mFoxP3 were associated with regulating the balance of T helper type 17 (Th17) and T(regs). These results suggest that PTD-mFoxP3 may be a candidate for RA therapy.

An RNA-binding complex involved in ribosome biogenesis contains a protein with homology to tRNA CCA-adding enzyme.

A multitude of proteins and small nucleolar RNAs transiently associate with eukaryotic ribosomal RNAs to direct their modification and processing and the assembly of ribosomal proteins. Utp22 and Rrp7, two interacting proteins with no recognizable domain, are components of the 90S preribosome or the small subunit processome that conducts early processing of 18S rRNA. Here, we determine the cocrystal structure of Utp22 and Rrp7 complex at 1.97 Å resolution and the NMR structure of a C-terminal fragment of Rrp7, which is not visible in the crystal structure. The structure reveals that Utp22 surprisingly resembles a dimeric class I tRNA CCA-adding enzyme yet with degenerate active sites, raising an interesting evolutionary connection between tRNA and rRNA processing machineries. Rrp7 binds extensively to Utp22 using a deviant RNA recognition motif and an extended linker. Functional sites on the two proteins were identified by structure-based mutagenesis in yeast. We show that Rrp7 contains a flexible RNA-binding C-terminal tail that is essential for association with preribosomes. RNA-protein crosslinking shows that Rrp7 binds at the central domain of 18S rRNA and shares a neighborhood with two processing H/ACA snoRNAs snR30 and snR10. Depletion of snR30 prevents the stable assembly of Rrp7 into preribosomes. Our results provide insight into the evolutionary origin and functional context of Utp22 and Rrp7.

Structural and functional analysis of Utp23, a yeast ribosome synthesis factor with degenerate PIN domain.

During synthesis of yeast ribosome, a large complex, called the 90S pre-ribosome or the small subunit processome, is assembled on the nascent precursor rRNA and mediates early processing of 18S rRNA. The Utp23 protein and snR30 H/ACA snoRNA are two conserved components of 90S pre-ribosomes. Utp23 contains a degenerate PIN nuclease domain followed by a long C-terminal tail and associates specifically with snR30. Here, we report the crystal structure of the Utp23 PIN domain at 2.5-Å resolution. The structure reveals a conserved core fold of PIN domain with degenerate active site residues, a unique CCHC Zn-finger motif, and two terminal extension elements. Functional sites of Utp23 have been examined with conservation analysis, mutagenesis, and in vivo and in vitro assays. Mutations in each of three cysteine ligands of zinc, although not the histidine ligand, were lethal or strongly inhibitory to yeast growth, indicating that the Zn-finger motif is required for Utp23 structure or function. The N-terminal helix extension harbors many highly conserved basic residues that mostly are critical for growth and in vitro RNA-binding activity of Utp23. Deletion of the C-terminal tail, which contains a short functionally important sequence motif, disrupted the interaction of Utp23 with snR30 and perturbed the pre-ribosomal association of Utp23. Our data establish a structural framework for dissecting Utp23 function in the assembly and dynamics of 90S pre-ribosomes.