Drought response revealed by chromatin organization variation and transcriptional regulation in cotton.

BACKGROUND: Cotton is a major world cash crop and an important source of natural fiber, oil, and protein. Drought stress is becoming a restrictive factor affecting cotton production. To facilitate the development of drought-tolerant cotton varieties, it is necessary to study the molecular mechanism of drought stress response by exploring key drought-resistant genes and related regulatory factors. RESULTS: In this study, two cotton varieties, ZY007 (drought-sensitive) and ZY168 (drought-tolerant), showing obvious phenotypic differences under drought stress, were selected. A total of 25,898 drought-induced genes were identified, exhibiting significant enrichment in pathways related to plant stress responses. Under drought induction, At subgenome expression bias was observed at the whole-genome level, which may be due to stronger inhibition of Dt subgenome expression. A gene co-expression module that was significantly associated with drought resistance was identified. About 90% of topologically associating domain (TAD) boundaries were stable, and 6613 TAD variation events were identified between the two varieties under drought. We identified 92 genes in ZY007 and 98 in ZY168 related to chromatin 3D structural variation and induced by drought stress. These genes are closely linked to the cotton response to drought stress through canonical hormone-responsive pathways, modulation of kinase and phosphatase activities, facilitation of calcium ion transport, and other related molecular mechanisms. CONCLUSIONS: These results lay a foundation for elucidating the molecular mechanism of the cotton drought response and provide important regulatory locus and gene resources for the future molecular breeding of drought-resistant cotton varieties.

N6-methyladenosine RNA modification regulates cotton drought response in a Ca2+ and ABA-dependent manner.

N6 -methyladenosine (m6 A) is the most prevalent internal modification present in mRNAs, and is considered to participate in a range of developmental and biological processes. Drought response is highly regulated at the genomic, transcriptional and post-transcriptional levels. However, the biological function and regulatory mechanism of m6 A modification in the drought stress response is still poorly understood. We generated a transcriptome-wide m6 A map using drought-resistant and drought-sensitive varieties of cotton under different water deficient conditions to uncover patterns of m6 A methylation in cotton response to drought stress. The results reveal that m6 A represents a common modification and exhibit dramatic changes in distribution during drought stress. More 5'UTR m6 A was deposited in the drought-resistant variety and was associated with a positive effect on drought resistance by regulating mRNA abundance. Interestingly, we observed that increased m6 A abundance was associated with increased mRNA abundance under drought, contributing to drought resistance, and vice versa. The demethylase GhALKBH10B was found to decrease m6 A levels, facilitating the mRNA decay of ABA signal-related genes (GhZEP, GhNCED4 and GhPP2CA) and Ca2+ signal-related genes (GhECA1, GhCNGC4, GhANN1 and GhCML13), and mutation of GhALKBH10B enhanced drought resistance at seedling stage in cotton. Virus-induced gene silencing (VIGS) of two Ca2+ -related genes, GhECA1 and GhCNGC4, reduced drought resistance with the decreased m6 A enrichment on silenced genes in cotton. Collectively, we reveal a novel mechanism of post-transcriptional modification involved in affecting drought response in cotton, by mediating m6 A methylation on targeted transcripts in the ABA and Ca2+ signalling transduction pathways.

Identification and Functional Analysis of bZIP Genes in Cotton Response to Drought Stress.

The basic leucine zipper (bZIP) transcription factors, which harbor a conserved bZIP domain composed of two regions, a DNA-binding basic region and a Leu Zipper region, operate as important switches of transcription networks in eukaryotes. However, this gene family has not been systematically characterized in cotton (Gossypium hirsutum). Here, we identified 197 bZIP family members in cotton. The chromosome distribution pattern indicates that the GhbZIP genes have undergone 53 genome-wide segmental and 7 tandem duplication events which contribute to the expansion of the cotton bZIP family. Phylogenetic analysis showed that cotton GhbZIP proteins cluster into 13 subfamilies, and homologous protein pairs showed similar characteristics. Inspection of the DNA-binding basic region and leucine repeat heptads within the bZIP domains indicated different DNA-binding site specificities as well as dimerization properties among different groups. Comprehensive expression analysis indicated the most highly and differentially expressed genes in root and leaf that might play significant roles in cotton response to drought stress. GhABF3D was identified as a highly and differentially expressed bZIP family gene in cotton leaf and root under drought stress treatments that likely controls drought stress responses in cotton. These data provide useful information for further functional analysis of the GhbZIP gene family and its potential application in crop improvement.

Phenomics-based GWAS analysis reveals the genetic architecture for drought resistance in cotton.

Drought resistance (DR) is a complex trait that is regulated by a variety of genes. Without comprehensive profiling of DR-related traits, the knowledge of the genetic architecture for DR in cotton remains limited. Thus, there is a need to bridge the gap between genomics and phenomics. In this study, an automatic phenotyping platform (APP) was systematically applied to examine 119 image-based digital traits (i-traits) during drought stress at the seedling stage, across a natural population of 200 representative upland cotton accessions. Some novel i-traits, as well as some traditional i-traits, were used to evaluate the DR in cotton. The phenomics data allowed us to identify 390 genetic loci by genome-wide association study (GWAS) using 56 morphological and 63 texture i-traits. DR-related genes, including GhRD2, GhNAC4, GhHAT22 and GhDREB2, were identified as candidate genes by some digital traits. Further analysis of candidate genes showed that Gh_A04G0377 and Gh_A04G0378 functioned as negative regulators for cotton drought response. Based on the combined digital phenotyping, GWAS analysis and transcriptome data, we conclude that the phenomics dataset provides an excellent resource to characterize key genetic loci with an unprecedented resolution which can inform future genome-based breeding for improved DR in cotton.

Combined GWAS and eQTL analysis uncovers a genetic regulatory network orchestrating the initiation of secondary cell wall development in cotton.

The cotton fibre serves as a valuable experimental system to study cell wall synthesis in plants, but our understanding of the genetic regulation of this process during fibre development remains limited. We performed a genome-wide association study (GWAS) and identified 28 genetic loci associated with fibre quality in allotetraploid cotton. To investigate the regulatory roles of these loci, we sequenced fibre transcriptomes of 251 cotton accessions and identified 15 330 expression quantitative trait loci (eQTL). Analysis of local eQTL and GWAS data prioritised 13 likely causal genes for differential fibre quality in a transcriptome-wide association study (TWAS). Characterisation of distal eQTL revealed unequal genetic regulation patterns between two subgenomes, highlighted by an eQTL hotspot (Hot216) that established a genome-wide genetic network regulating the expression of 962 genes. The primary regulatory role of Hot216, and specifically the gene encoding a KIP-related protein, was found to be the transcriptional regulation of genes responsible for cell wall synthesis, which contributes to fibre length by modulating the developmental transition from rapid cell elongation to secondary cell wall synthesis. This study uncovered the genetic regulation of fibre-cell development and revealed the molecular basis of the temporal modulation of secondary cell wall synthesis during plant cell elongation.

GhL1L1 affects cell fate specification by regulating GhPIN1-mediated auxin distribution.

Auxin is as an efficient initiator and regulator of cell fate during somatic embryogenesis (SE), but the molecular mechanisms and regulating networks of this process are not well understood. In this report, we analysed SE process induced by Leafy cotyledon1-like 1 (GhL1L1), a NF-YB subfamily gene specifically expressed in embryonic tissues in cotton. We also identified the target gene of GhL1L1, and its role in auxin distribution and cell fate specification during embryonic development was analysed. Overexpression of GhL1L1 accelerated embryonic cell formation, associated with an increased concentration of IAA in embryogenic calluses (ECs) and in the shoot apical meristem, corresponding to altered expression of the auxin transport gene GhPIN1. By contrast, GhL1L1-deficient explants showed retarded embryonic cell formation, and the concentration of IAA was decreased in GhL1L1-deficient ECs. Disruption of auxin distribution accelerated the specification of embryonic cell fate together with regulation of GhPIN1. Furthermore, we showed that PHOSPHATASE 2AA2 (GhPP2AA2) was activated by GhL1L1 through targeting the G-box of its promoter, hence regulating the activity of GhPIN1 protein. Our results indicate that GhL1L1 functions as a key regulator in auxin distribution to regulate cell fate specification in cotton and contribute to the understanding of the complex process of SE in plant species.

Crosstalk between cytokinin and ethylene signaling pathways regulates leaf abscission in cotton in response to chemical defoliants.

Abscission is a process that allows plants to shed tissues or organs via cell separation, and occurs throughout the life cycle. Removal of leaves through the use of chemical defoliants is very important for mechanical harvesting of cotton (Gossypium hirsutum). However, our knowledge of the molecular mechanisms of the defoliation response involved is limited. In this study, RNA-seq was conducted in order to profile the differentially expressed genes (DEGs) between cultivars X50 (sensitive to chemical defoliants) and X33 (relatively insensitive) at different time points after treatment with thidiazuron and ethephon (TE). A total of 2434 DEGs were identified between the two cultivars across the different time-points. Functional categories according to GO and KEGG analyses revealed that plant hormone signal transduction and zeatin biosynthesis were involved in the response to TE. Cytokinin oxidase/dehydrogenase (CKX) genes and ethylene-related genes were up-regulated following TE treatment, and were associated with increased level of ethylene, especially in cultivar X50. Down-regulation of GhCKX3 resulted in delayed defoliation and a reduced ethylene response. The results show that crosstalk between cytokinin and ethylene regulates cotton defoliation, and provide new insights into the molecular mechanisms underlying the mode of action of defoliants in cotton.

Implants coating strategies for antibacterial treatment in fracture and defect models: A systematic review of animal studies.

Objective: Fracture-related infection (FRI) remains a major concern in orthopaedic trauma. Functionalizing implants with antibacterial coatings are a promising strategy in mitigating FRI. Numerous implant coatings have been reported but the preventive and therapeutic effects vary. This systematic review aimed to provide a comprehensive overview of current implant coating strategies to prevent and treat FRI in animal fracture and bone defect models. Methods: A literature search was performed in three databases: PubMed, Web of Science and Embase, with predetermined keywords and criteria up to 28 February 2023. Preclinical studies on implant coatings in animal fracture or defect models that assessed antibacterial and bone healing effects were included. Results: A total of 14 studies were included in this systematic review, seven of which used fracture models and seven used defect models. Passive coatings with bacteria adhesion resistance were investigated in two studies. Active coatings with bactericidal effects were investigated in 12 studies, four of which used metal ions including Ag+ and Cu2+; five studies used antibiotics including chlorhexidine, tigecycline, vancomycin, and gentamicin sulfate; and the other three studies used natural antibacterial materials including chitosan, antimicrobial peptides, and lysostaphin. Overall, these implant coatings exhibited promising efficacy in antibacterial effects and bone formation. Conclusion: Antibacterial coating strategies reduced bacterial infections in animal models and favored bone healing in vivo. Future studies of implant coatings should focus on optimal biocompatibility, antibacterial effects against multi-drug resistant bacteria and polymicrobial infections, and osseointegration and osteogenesis promotion especially in osteoporotic bone by constructing multi-functional coatings for FRI therapy. The translational potential of this paper: The clinical treatment of FRI is complex and challenging. This review summarizes novel orthopaedic implant coating strategies applied to FRI in preclinical studies, and offers a perspective on the future development of orthopaedic implant coatings, which can potentially contribute to alternative strategies in clinical practice.

In Situ Synthesis of an Immune-Checkpoint Blocker from Engineered Bacteria Elicits a Potent Antitumor Response.

Immune-checkpoint blockade (ICB) reinvigorates T cells from exhaustion and potentiates T-cell responses to tumors. However, most patients do not respond to ICB therapy, and only a limited response can be achieved in a "cold" tumor with few infiltrated lymphocytes. Synthetic biology can be used to engineer bacteria as controllable bioreactors to synthesize biotherapeutics in situ. We engineered attenuated Salmonella VNP20009 with synthetic gene circuits to produce PD-1 and Tim-3 scFv to block immunosuppressive receptors on exhausted T cells to reinvigorate their antitumor response. Secreted PD-1 and Tim-3 scFv bound PD-1+ Tim-3+ T cells through their targeting receptors in vitro and potentiated the T-cell secretion of IFN-γ. Engineered bacteria colonized the hypoxic core of the tumor and synthesized PD-1 and Tim-3 scFv in situ, reviving CD4+ T cells and CD8+ T cells to execute an antitumor response. The bacteria also triggered a strong innate immune response, which stimulated the expansion of IFN-γ+ CD4+ T cells within the tumors to induce direct and indirect antitumor immunity.

Comprehensive non-coding RNA analysis reveals specific lncRNA/circRNA-miRNA-mRNA regulatory networks in the cotton response to drought stress.

Root and leaf are essential organs of plants in sensing and responding to drought stress. However, comparative knowledge of non-coding RNAs (ncRNAs) of root and leaf tissues in the regulation of drought response in cotton is limited. Here, we used deep sequencing data of leaf and root tissues of drought-resistant and drought-sensitive cotton varieties for identifying miRNAs, lncRNAs and circRNAs. A total of 1531 differentially expressed (DE) ncRNAs was identified, including 77 DE miRNAs, 1393 DE lncRNAs and 61 DE circRNAs. The tissue-specific and variety-specific competing endogenous RNA (ceRNA) networks of DE lncRNA-miRNA-mRNA response to drought were constructed. Furthermore, the novel drought-responsive lncRNA 1 (DRL1), specifically and differentially expressed in root, was verified to positively affect phenotypes of cotton seedlings under drought stress, competitively binding to miR477b with GhNAC1 and GhSCL3. In addition, we also constructed another ceRNA network consisting of 18 DE circRNAs, 26 DE miRNAs and 368 DE mRNAs. Fourteen circRNA were characterized, and a novel molecular regulatory system of circ125- miR7484b/miR7450b was proposed under drought stress. Our findings revealed the specificity of ncRNA expression in tissue- and variety-specific patterns involved in the response to drought stress, and uncovered novel regulatory pathways and potentially effective molecules in genetic improvement for crop drought resistance.

Engineered Cell Membrane Vesicles Expressing CD40 Alleviate System Lupus Nephritis by Intervening B Cell Activation.

Immune intervention of B cell activation to blockade the production of autoantibodies provokes intense interest in the field of systemic lupus erythematosus (SLE) therapy development. Although the survival rate for SLE is improved, many patients die untimely. Engineered cell membrane vesicles manifest remarkable capacity of targeted drug delivery and immunomodulation of immune cells such as B cells. Herein, this work engineered cellular nanovesicles (NVs) presenting CD40 (CD40 NVs) that can blunt B cells and thus alleviate SLE. CD40 NVs disrupt the CD40/CD40 ligand (CD40L) costimulatory signal axis through the blockade of CD40L on CD4+ T cells. Therefore, the CD40 NVs restrain the generation of the germinal center structure and production of antibodies from B cells. Furthermore, immunosuppressive drug mycophenolate mofetil (MMF) is also encapsulated in the vesicles (MMF-CD40 NVs), which is employed to deplete immunocytes including B cells, T cells, and dendritic cells. Together, CD40 NVs are promising formulations for relieving autoimmunity and lupus nephritis in MRL/lpr mice.

Effectiveness of the combination of workshops and flipped classroom model to improve tube fixation training for nursing students.

BACKGROUND: Tube indwelling is a key procedure in modern medicine. Careful tube setup is necessary to prevent unplanned extubation. The training for tube fixation is time- and resource-consuming, and optimal modes of training are currently being sought. Previous studies have compared workshops and flipped classroom models separately using conventional teaching strategies, but no study has examined a combination of both teaching models in nursing training. AIM: To compare the effectiveness of workshops vs workshops combined with the flipped classroom model for improving tube fixation training for nursing students. METHODS: This was a prospective cohort study. In this study, 149 nurses who joined our hospital in 2019 underwent training using workshops combined with the flipped classroom model (experimental group), while 159 nurses who joined the hospital in 2018 received only workshop-based training (control group). The combination of workshops with the flipped classroom training model was divided into two modules: pre-class and in-class training. The participation of nurses in the training activities, on-site assessment of training, nurses' evaluation of their training, and related indicators of tube quality management were evaluated. RESULTS: The average age of nurses in the control group was 22.94 ± 0.94 years and that of nurses in the experimental group was 25.42 ± 3.23 years (P < 0.01). The qualified rate of after-class assessments for the experimental and control groups was 100.00% (average score: 94.01 ± 2.78 points) and 91.82% (average score: 84.24 ± 2.94 points), respectively (P < 0.01). Most nurses in the experimental group completely agreed that the combined training was helpful to cultivate clinical thinking and independent learning ability and to master knowledge of tube fixation. In addition, the training content within the pre-class teaching video, pre-class tube atlas, pre-class main instructor guidance, in-class demonstration, and in-class practice was very informative. The experimental group had higher evaluation scores than the control group (4.88 ± 0.38 vs 4.67 ± 0.64; P < 0.01). Comparison of tube quality management before and after training in 2018 to 2019 revealed that the unplanned ureteral tube removal rate dropped from 0.25‰ to 0.06‰, the unplanned chest tube removal rate dropped from 1.07‰ to 0.78‰, and the unplanned gastric tube removal rate dropped from 0.36‰ to 0.17‰. The incidence rate of pressure ulcers caused by the tube decreased from 0.78‰ to 0.45‰. CONCLUSION: The combination of workshop and flipped classroom training is effective in improving tube fixation training of nurses, cultivating nurses' active learning abilities and clinical thinking, and improving the safety of the procedure.

Adapting the depression component of WHO Mental Health Gap Intervention Guide (mhGAP-IG.v2) for primary care in Shenzhen, China: a DELPHI study.

BACKGROUND: Primary care doctors in Shenzhen, China are increasingly expected to identify and prevent depressive disorder; however, they have received limited mental health training and community healthcare centres (CHC) do not provide standardised protocols for the diagnosis and care of depressive disorder. The World Health Organization's mental health gap intervention guide, version 2 (mhGAP-IG.v2) is a decision support tool for non-specialists for the assessment, management and follow-up of mental, neurological and substance use disorders (including depressive disorder). Given that mhGAP-IG.v2 is a generic tool, it requires adaptation to take account of cultural differences in depression presentation and unique characteristics of China's emergent mental health system. METHODS: A two-round, web-based, Delphi survey was conducted. A panel of primary care doctors from Shenzhen, were invited to score their level of agreement with 199 statements (arranged across 10 domains) proposing changes to the content and structure of mhGAP-IG.v2 for use in Shenzhen. Consensus was predefined as 80% panelists providing a rating of either "somewhat agree/definitely agree", or "definitely disagree/somewhat disagree" on a five-point scale for agreement. RESULTS: 79% of statements received consensus with a mean score of 4.26 (i.e. "somewhat agree"). Agreed adaptations for mhGAP-IG.v2 included:- an assessment approach which considers a broader spectrum of depression symptoms and reflects the life course of disease; incorporating guidance for screening tool usage; clarifying physicians' roles and including referral pathways for intersectorial care with strong family involvement; aligning drug treatment with national formularies; stronger emphasis of suicide prevention throughout all sections of the guide; contextualizing health education; reflecting a person-centred approach to care. Panelists chose to maintain diagnostic and treatment advice for bipolar patients experiencing a depressive episode as in the current guide. CONCLUSIONS: An adapted mhGAP-IG.v2 for depression recognises China's cultural and contextual needs for assessment guidance; unique primary healthcare system organization, priorities and treatment availability; and diverse psychosocial educational needs. An adapted mhGAP-IG.v2 could both inform the future training programs for primary care in Shenzhen and also offer an additional mental health resource for non-specialists in other countries.

Cirrhosis of Wilson's disease: High and low cutoff using acoustic radiation force impulse (ARFI) -Comparison and combination with serum fibrosis index.

BACKGROUND: Acoustic Radiation Force Impulse (ARFI), Fibrosis-4(FIB-4) and Aspartate transaminase to platelet ratio index (APRI) are valuable non-invasive methods to evaluate fibrosis in hepatitis virus. Yet, they are rarely used in Wilson's disease. OBJECTIVE: Evaluate the diagnostic efficacy of ARFI, FIB-4, APRI, combined detection in cirrhosis with WD, and speculate the optimal high, low cutoff. METHODS: This retrospective study was authorized by hospital ethics Committee (number:2021MCZQ02). 102 patients with WD completed ARFI and laboratory examination on the same day. The intraclass correlation coeffcient (ICC) of ARFI among three sonographers was 0.896 (95%CI:0.859-0.925, p = 0.000). The stage of liver involvement was classified into 5 categories according to clinical manifestations, laboratory examination, and liver morphologic characteristics: I, normal; II, biochemical abnormal only; III, abnormal liver morphologic features without sighs of cirrhosis; IV, clinical and imaging sighs of compensateded cirrhosis (Child-Pugh A); V, decompensated cirrhosis (Child-Pugh B and C). This stage system served as the reference standard. The diagnostic efficacy was analyzed by Logistic regression, ROC curve. The optimal low cut-off with high sensitivity (SE) and low negative likelihood ratio (NLR) and high cut-off with high specificity (SP) and positive likelihood ratio (PLR) were derived. RESULTS: The diagnostic value of ARFI (0.85, 95%CI:0.77-0.92, p = 0.000) in distiguishing cirrhosis with WD was higher than FIB-4 (0.59, 95%CI: 0.47-0.70, p = 0.127), APRI (0.70, 95%CI: 0.59-0.81, p = 0.000). The low, high cut-off of ARFI for excluding, diagnosing cirrhosis with WD was 1.47 m/s(SE: 98%, NLR:0.09), 2.11 m/s(SP:98%, PLR:27.4), 37 (36%) patients could be spared a liver biopsy. When ARFI was 1.47∼2.11 m/s, liver biopsy was recommended. After combined with ARFI, the AUROC of FIB-4, APRI were increased respectively (p < 0.001), there were not different between ARFI and combined detection(p >  0.05). CONCLUSION: ARFI could replace some unnecessary liver biopsy according to high diagnostic efficacy for identifying cirrhosis of WD. The combined detection can also be used as an important model to predict cirrhosis in WD.

Genetic engineering cellular vesicles expressing CD64 as checkpoint antibody carrier for cancer immunotherapy.

Immune checkpoint blockade therapies, especially those targeting the programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) have achieved impressive clinical responses in multiple types of cancers. To optimize the therapeutic effect of the checkpoint antibodies, many strategies including targeting delivery, controlled release, and cellular synthesis have been developed. However, within these strategies, antibodies were attached to drug carriers by chemical bonding, which may affect the steric configuration and function of the antibodies. Herein, we prepared cluster of differentiation 64 (CD64), a natural catcher of the fragment crystalline (Fc) of monomeric immunoglobulin G (IgG), and over-expressed it on the cell membrane nanovesicles (NVs) as PD-L1 antibody delivery vehicle (CD64-NVs-aPD-L1), which was employed to disrupt the PD-1/PD-L1 immunosuppressive signal axis for boosting T cell dependent tumor elimination. Meanwhile, chemical immunomodulatory drug cyclophosphamide (CP) was also encapsulated in the vesicle (CD64-NVs-aPD-L1-CP), to simultaneously restrain the regulatory T cells (Tregs) and invigorate Ki67+CD8+ T cells, then further enhance their anti-tumor ability. Methods: The cell membrane NVs overexpressing CD64 were incubated with PD-L1 antibody and chemotherapeutic agent CP to prepare CD64-NVs-aPD-L1-CP. Results: The CD64-NVs-aPD-L1-CP could simultaneously interrupt the immunosuppressive effect of PD-L1 and decrease the inhibition of Tregs, leading to tumor growth suppression and survival time extension. Conclusion: CD64-NVs are charismatic carriers to achieve both checkpoint blockade and immunomodulatory drugs for combined cancer immunotherapy.

Erratum.

Overexpression of the tumor necrosis factor receptor-associated factor 4 (TRAF4) has been detected in many cancer types and is considered to foster tumor progression. However, the role of TRAF4 in hepatocellular carcinoma (HCC) remains elusive. In this study, we found that TRAF4 was highly expressed in HCC cell lines and HCC tissues compared with normal liver cell lines and adjacent noncancerous tissues. TRAF4 overexpression in HCC tissues was correlated with tumor quantity and vascular invasion. In vitro studies showed that TRAF4 was associated with HCC cell migration and invasion. An in vivo study verified that TRAF4 overexpression facilitated metastasis in nude mice. In addition, overexpressed TRAF4 promoted the phosphorylation of Akt and induced Slug overexpression, leading to downregulated E-cadherin and upregulated vimentin, while silencing TRAF4 moderated the phosphorylation of Akt and repressed the expression of Slug, which resulted in upregulated E-cadherin and downregulated vimentin. These effects were inversed after pretreatment of the PI3K/Akt inhibitor LY294002 or overexpression of constitutively active Akt1. Our study demonstrated that TRAF4 was involved in promoting HCC cell migration and invasion. The process was induced by the EMT through activation of the PI3K/Akt signaling pathway.

Contribution of tissue transglutaminase to the severity of hepatic fibrosis resulting from Schistosoma japonicum infection through the regulation of IL-33/ST2 expression.

BACKGROUND: Tissue transglutaminase (tTG)-regulating IL-13 plays an important role in the pathogenesis of liver fibrosis resulting from Schistosoma japonicum (Sj) infection. IL-33 and its receptor ST2 are involved in Th2-biased immune responses through the release of IL-5 and IL-13 and subsequent hepatic granuloma pathology induced by Sj infection. However, the relationship between tTG, IL-33/ST2, and liver fibrosis during Schistosoma infection has not been established. RESULTS: This study investigated the link between tTG and IL-33/ST2 in the induction of liver fibrogenesis during Sj infection in mice. The extent of liver fibrosis coincided with an increase in tTG and IL-33/ST2 expression in the liver of infected mice between five to eight weeks, with a peak of correlation at six weeks after Sj infection. The inhibition of tTG activity through cystamine administration or gene knockout alleviated the level of TLR4, NF-κB pathway molecules, IL-33/ST2, and the severity of liver fibrosis resulting from Sj infection. CONCLUSIONS: These results indicate that during Sj infection tTG may control liver fibrosis at least partially through TLR4, NF-κB pathway activation and then IL-33/ST2. tTG, IL-33 or ST2 might be promising drug targets against liver fibrosis induced by Sj infection.

Reference genome sequences of two cultivated allotetraploid cottons, Gossypium hirsutum and Gossypium barbadense.

Allotetraploid cotton species (Gossypium hirsutum and Gossypium barbadense) have long been cultivated worldwide for natural renewable textile fibers. The draft genome sequences of both species are available but they are highly fragmented and incomplete1-4. Here we report reference-grade genome assemblies and annotations for G. hirsutum accession Texas Marker-1 (TM-1) and G. barbadense accession 3-79 by integrating single-molecule real-time sequencing, BioNano optical mapping and high-throughput chromosome conformation capture techniques. Compared with previous assembled draft genomes1,3, these genome sequences show considerable improvements in contiguity and completeness for regions with high content of repeats such as centromeres. Comparative genomics analyses identify extensive structural variations that probably occurred after polyploidization, highlighted by large paracentric/pericentric inversions in 14 chromosomes. We constructed an introgression line population to introduce favorable chromosome segments from G. barbadense to G. hirsutum, allowing us to identify 13 quantitative trait loci associated with superior fiber quality. These resources will accelerate evolutionary and functional genomic studies in cotton and inform future breeding programs for fiber improvement.

[Factors influencing the content of residual tert-butyl alcohol in cyclodextrin complex prepared by lyophilization cosolvent system].

In order to minimize the residual tert-butyl alcohol (TBA) level in cyclodextrin complex prepared by freeze drying TBA/water cosolvent system, the formulation and lyophilization procedure that may influence the residual TBA was studied. Residual TBA in freeze dried cyclodextrin complex was determined by gas chromatography. The significant formulation and processing factors that influence residual TBA were identified by adjusting the initial TBA concentration in cosolvent, selecting cyclodextrin type (beta-cyclodextrin or hydroxypropyl beta-cyclodextrin), changing sample volume in flasket, altering freezing mode (fast freezing or slow freezing) and modifying the duration of secondary drying. The results show that the amorphous cyclodextrin material (hydroxypropyl beta-cyclodextrin), initial low TBA concentration in cosolvent and fast freezing would lead to high TBA residue in cyclodextrin complex, annealing was effective in reducing the residual TBA. The duration of secondary drying had no distinct effect on residual TBA. It is concluded that in order to reduce residual TBA in cyclodextrin complex prepared by lyophilization monophase solution, the initial TBA concentration in cosolvent should be higher than the crystal formation concentration, the appropriate cyclodextrin type and freeze drying processing should be choosen.

TRAF4 Regulates Migration, Invasion, and Epithelial-Mesenchymal Transition via PI3K/AKT Signaling in Hepatocellular Carcinoma.

Overexpression of the tumor necrosis factor receptor-associated factor 4 (TRAF4) has been detected in many cancer types and is considered to foster tumor progression. However, the role of TRAF4 in hepatocellular carcinoma (HCC) remains elusive. In this study, we found that TRAF4 was highly expressed in HCC cell lines and HCC tissues compared with normal liver cell lines and adjacent noncancerous tissues. TRAF4 overexpression in HCC tissues was correlated with tumor quantity and vascular invasion. In vitro studies showed that TRAF4 was associated with HCC cell migration and invasion. An in vivo study verified that TRAF4 overexpression facilitated metastasis in nude mice. In addition, overexpressed TRAF4 promoted the phosphorylation of Akt and induced Slug overexpression, leading to downregulated E-cadherin and upregulated vimentin, while silencing TRAF4 moderated the phosphorylation of Akt and repressed the expression of Slug, which resulted in upregulated E-cadherin and downregulated vimentin. These effects were inversed after pretreatment of the PI3K/Akt inhibitor LY294002 or overexpression of constitutively active Akt1. Our study demonstrated that TRAF4 was involved in promoting HCC cell migration and invasion. The process was induced by the EMT through activation of the PI3K/Akt signaling pathway.