Engineering natural microbiomes toward enhanced bioremediation by microbiome modeling.

Engineering natural microbiomes for biotechnological applications remains challenging, as metabolic interactions within microbiomes are largely unknown, and practical principles and tools for microbiome engineering are still lacking. Here, we present a combinatory top-down and bottom-up framework to engineer natural microbiomes for the construction of function-enhanced synthetic microbiomes. We show that application of herbicide and herbicide-degrader inoculation drives a convergent succession of different natural microbiomes toward functional microbiomes (e.g., enhanced bioremediation of herbicide-contaminated soils). We develop a metabolic modeling pipeline, SuperCC, that can be used to document metabolic interactions within microbiomes and to simulate the performances of different microbiomes. Using SuperCC, we construct bioremediation-enhanced synthetic microbiomes based on 18 keystone species identified from natural microbiomes. Our results highlight the importance of metabolic interactions in shaping microbiome functions and provide practical guidance for engineering natural microbiomes.

Tertiary lymphoid structural heterogeneity determines tumour immunity and prospects for clinical application.

Tertiary lymphoid structures (TLS) are clusters of immune cells that resemble and function similarly to secondary lymphoid organs (SLOs). While TLS is generally associated with an anti-tumour immune response in most cancer types, it has also been observed to act as a pro-tumour immune response. The heterogeneity of TLS function is largely determined by the composition of tumour-infiltrating lymphocytes (TILs) and the balance of cell subsets within the tumour-associated TLS (TA-TLS). TA-TLS of varying maturity, density, and location may have opposing effects on tumour immunity. Higher maturity and/or higher density TLS are often associated with favorable clinical outcomes and immunotherapeutic response, mainly due to crosstalk between different proportions of immune cell subpopulations in TA-TLS. Therefore, TLS can be used as a marker to predict the efficacy of immunotherapy in immune checkpoint blockade (ICB). Developing efficient imaging and induction methods to study TA-TLS is crucial for enhancing anti-tumour immunity. The integration of imaging techniques with biological materials, including nanoprobes and hydrogels, alongside artificial intelligence (AI), enables non-invasive in vivo visualization of TLS. In this review, we explore the dynamic interactions among T and B cell subpopulations of varying phenotypes that contribute to the structural and functional diversity of TLS, examining both existing and emerging techniques for TLS imaging and induction, focusing on cancer immunotherapies and biomaterials. We also highlight novel therapeutic approaches of TLS that are being explored with the aim of increasing ICB treatment efficacy and predicting prognosis.

Screening of Spinal Muscular Atrophy Carriers and Prenatal Diagnosis in Pregnant Women in Yancheng, China.

Spinal muscular atrophy (SMA) is a neuromuscular disorder with an autosomal recessive inheritance pattern. Patients with severe symptoms may suffer respiratory failure, leading to death. The homozygous deletion of exon 7 in the SMN1 gene accounts for nearly 95% of all cases. Population carrier screening for SMA and prenatal diagnosis by amniocentesis for high-risk couples can assist in identifying the risk of fetal disease. We provided the SMA carrier screening process to 55,447 pregnant women in Yancheng from October 2020 to December 2022. Among them, 8185 participated in this process, with a participation rate of around 14.76% (95% CI 14.47-15.06%). Quantitative real-time polymerase chain reaction (qPCR) was used to detect deletions of SMN1 exons 7 and 8 (E7, E8) in screened pregnant women. 127 were identified as carriers (111 cases of E7 and E8 heterozygous deletions, 15 cases of E7 heterozygous deletions, and 1 case of E7 heterozygous deletions and E8 homozygous deletions), resulting in a carrying rate of around 1.55% (95% CI 1.30-1.84%). After genetic counseling, 114 spouses of pregnant women who tested positive underwent SMA carrier screening; three of them were screened as SMA carriers. Multiplexed ligation-dependent probe amplification (MLPA) was used for the prenatal diagnosis of the fetuses of high-risk couples. Two of them exhibited two copies of SMN1 exon 7 (normal), and the pregnancy was continued; one exhibited no copies of SMN1 exon 7 and exon 8 (SMA patient), and the pregnancy was terminated. Analyzing SMN1 mutations in Yancheng and provide clinical evidence for SMA genetic counseling and birth defect prevention. Interventional prenatal diagnosis for high-risk families can promote informed reproductive selection and prepare for the fetus's early treatment.

Deep-Learning-Based Nanomechanical Vibration for Rapid and Label-Free Assay of Epithelial Mesenchymal Transition.

Cancer is a profound danger to our life and health. The classification and related studies of epithelial and mesenchymal phenotypes of cancer cells are key scientific questions in cancer research. Here, we investigated cancer cell colonies from a mechanical perspective and developed an assay for classifying epithelial/mesenchymal cancer cell colonies using the biomechanical fingerprint in the form of "nanovibration" in combination with deep learning. The classification method requires only 1 s of vibration data and has a classification accuracy of nearly 92.5%. The method has also been validated for the screening of anticancer drugs. Compared with traditional methods, the method has the advantages of being nondestructive, label-free, and highly sensitive. Furthermore, we proposed a perspective that subcellular structure influences the amplitude and spectrum of nanovibrations and demonstrated it using experiments and numerical simulation. These findings allow internal changes in the cell colony to be manifested by nanovibrations. This work provides a perspective and an ancillary method for cancer cell phenotype diagnosis and promotes the study of biomechanical mechanisms of cancer progression.

Comparison of ciprofol-alfentanil and propofol-alfentanil sedation during bidirectional endoscopy: A prospective, double-blind, randomised, controlled trial.

BACKGROUND: Although propofol is widely used for gastrointestinal endoscopic sedation, cardiopulmonary adverse events remain common. Ciprofol is a new intravenous anaesthetic agent demonstrating respiratory and hemodynamic stability. AIMS: This study aimed to clarify the benefits of ciprofol combined with alfentanil in bidirectional endoscopy (esophagogastroduodenoscopy followed by colonoscopy) to reduce adverse events and improve post-endoscopic recovery. METHODS: A total of 185 patients scheduled to undergo bidirectional endoscopy were randomly divided into two groups: ciprofol combined with alfentanil or propofol combined with alfentanil. All patients received 7 µg/kg alfentanil intravenously before the study drugs were administered. The propofol group received a bolus of 1.2 mg/kg (0.12 ml/kg) propofol intravenously, whereas the ciprofol group received a bolus of 0.3 mg/kg (0.12 ml/kg) ciprofol intravenously. The primary outcome was the proportion of patients with cardiopulmonary adverse events (i.e., any one of the airway obstruction, apnoea, hypotension, hypertension, bradycardia, tachycardia or arrhythmias). RESULTS: Compared with propofol, ciprofol reduced cardiopulmonary adverse events by 43.51 % (34.4% vs. 60.9 %, P <0.001), mitigated respiratory adverse events by 54.74 % (17.2% vs. 38.0 %, P = 0.002) overall and by 59.05 % (12.9% vs. 31.5 %, P = 0.002) during the induction period. CONCLUSIONS: Ciprofol can significantly decrease respiratory depression events and provides a better sedative efficacy than propofol with higher recovery quality and satisfaction.

Recombinant human adenovirus p53 combined with transcatheter arterial chemoembolization for liver cancer: A meta-analysis.

OBJECTIVES: To compare the clinical curative effects, survival and complications of recombinant human adenovirus-p53 (rAd-p53) combined with transcatheter arterial chemoembolization (TACE) versus TACE for the treatment of liver cancer. METHODS: We searched all the eligible studies of rAd-p53 plus TACE versus control group had only TACE in the treatment of liver cancer, which were retrieved from CNKI, Wanfang database, CBM, VIP, PubMed, EMBase, The Chrance of Library, Web of Science from its inception to august 2022. RESULTS: A total of 17 studies were included, which involved 1045 patients. The results of the meta analysis indicated that the the rAd-p53combined with TACE markedly improved the patients' complete remission(OR = 2.19, 95% CI:1.13-4.22, P = 0.02), partial remission (OR = 2.22, 95% CI:1.67-2.94, P<0.00001), objective tumor response rate (OR = 2.58, 95% CI:1.95-3.41, P<0.00001) and disease control rate(OR = 2.39, 95% CI:1.65-3.47, P<0.00001) compared with TACE alone. And our results showed that rAd-p53combined with TACE had better survival benefit [6-month OS (OR = 3.41, 95% CI: 1.62-7.14, p = 0.001); 1-year OS (OR = 1.95, 95% CI: 1.28-2.96, p = 0.002)] and better quality of life(MD = 5.84, 95% CI:2.09-9.60, P = 0.002). In addition, the immunity of the patients was enhanced by the combination therapy, as demonstrated by the increase in the ratio of CD4+ to CD4+/CD8+. In adverse effects, except for fever in the TACE combined with rAd-p53 group, which was higher than that in the TACE group(OR = 2.62, 95% CI:2.02-3.49, P<0.00001), all other adverse effects were lower in the TACE combined with rAd-p53 group than in the TACE group. CONCLUSION: RAd-p53 combined with TACE for liver cancer showed significant advantages in terms of clinical efficacy, survival rate, and safety compared to the TACE alone, and effectively improved patient quality of life and immune function. SYSTEMATIC REVIEW REGISTRATION: https://inplasy.com/inplasy-2022-9-0127/.

Efficacy, safety, and Pharmacoeconomics of Three Common Strategies for Pediatric Alopecia Areata Patients: A Retrospective Cohort Study.

Objective: To evaluate and explore the efficacy, safety, and pharmacoeconomics of three common strategies for pediatric alopecia areata. Methods: Chinese pediatric alopecia areata patients meeting the criteria were included and divided into three groups based on the received treatments. The efficacy, adverse events and pharmacoeconomics of these treatments were retrospectively analyzed. Results: Twenty-four pediatric AA patients were recruited in this study. 100% (12/12) of patients from the traditional group achieved SALT100. In the tofacitinib group, 40.0% (2/5) of patients achieved SALT50. 20.0% (1/5) of patients achieved SALT75 and 40.0% (2/5) of patients achieved SALT100. In the MN group, 42.86% (3/7) of patients were non-responders. 14.28 (1/7) of patients achieved SALT75 and 42.86% (3/7) of patients achieved SALT100. The adverse effects (AEs) were mild in all three groups, and none of the patients discontinued the treatments due to the AEs. Comparing the other two groups, the MN treatment would be more time-intensive and more expensive. Conclusion: For newly diagnosed or naive pediatric patients, the traditional treatment was the first-line approach. For long-duration, severe and refractory patients, tofacitinib and microneedling can be alternative options.

Treatment of dissecting cellulitis of the scalp with erbium: YAG laser: a case series.

Dissecting cellulitis of the scalp (DCS) is a rare recurrent inflammatory disease of unknown etiology. Ideal treatment of DCS remains unclear. We treated DCS with 2940-nm erbium Yttrium-aluminum-garnet (YAG) laser in 12 patients and assessed the efficacy by Physicians Global Assessment (PGA), number of inflammatory nodules, abscesses, and area of alopecia. After a mean treating session of 2.2 months, 10 patients reached PGA 0 (initial PGA 1) or 1 (initial PGA ≥2). At the end of treatment, there was 84%, 100%, and 74% regression in nodules, abscesses, and alopecia area, respectively. No severe adverse effect was observed. 2940-nm erbium: YAG laser may be an effective and safe way to treat DCS resistant to other therapies.

[Tracking Riverine Nitrate Sources and Transformations in the Yiluo River Basin by Nitrogen and Oxygen Isotopes].

The impacts of natural processes and anthropogenic input on riverine nitrate (NO-3) could be identified by NO-3 concentrations and nitrogen and oxygen isotope ratios (δ15N-NO-3 and δ18O-NO-3); however, the effects of variable land use on riverine NO-3 sources and transformations remain unclear. In particular, the human impacts on riverine NO-3 in mountain areas are still unknown. The Yihe River and Luohe River were used to elucidate this question due to their spatially heterogeneous land use. Hydrochemical compositions, water isotope ratios (δD-H2O and δ18O-H2O), and δ15N-NO-3 and δ18O-NO-3 values were utilized to constrain the NO-3 sources and transformations affected by different land use types. The results indicated that ① the mean nitrate concentrations in the Yihe River and Luohe River waters were 6.57 and 9.29 mg·L-1, the mean values of δ15N-NO-3 were 9.6‰ and 10.4‰, and the average δ18O-NO-3 values were -2.2‰ and -2.7‰, respectively. Based on the analysis of δ15N-NO-3 and δ18O-NO-3 values, the NO-3 in the Yihe and Luohe Rivers were derived from multiple sources, and nitrogen removal existed in the Luohe River, but the biological removal in the Yihe River was weak. ② The contributions of different nitrate sources were calculated using a Bayesian isotope mixing model (BIMM) based on δ15N-NO-3 and δ18O-NO-3 values of river water in the mainstream and tributaries with spatial locations. The results revealed that sewage and manure had major impacts on riverine nitrate in the upper reaches of both the Luohe River and Yihe River, where forest vegetation was widely distributed. However, the contributions from soil organic nitrogen and chemical fertilizer were higher in the upper reaches than in downstream ones. The contributions of sewage and manure still increased in the downstream reaches. Our results confirmed the primary impacts of point sources, e.g., sewage and manure, on riverine nitrate in the studied area, and the contributions of nonpoint sources, e.g., chemical fertilizer, had not increased as the agricultural activities elevated the downstream. Therefore, more attention should be paid to point source pollution treatment, and the high-quality development of ecological civilization in the Yellow River Basin should be maintained.

Identification of a Novel Mutation of Extracellular Matrix Protein 1 Gene in a Chinese Family with Lipoid Proteinosis.

Lipoid proteinosis (LP) is a rare autosomal recessive disorder caused by mutations in extracellular matrix protein 1 (ECM1), a glycoprotein expressed in skin. Whole-exome sequencing (WES) was used to investigate two Chinese siblings with suggestive clinical features of LP. They shared one known (c.960G>A) and one novel (c.1081G>T) pathogenic variant in ECM1 gene, inherited from their unaffected parents. The novel mutation (c.1081G>T) led to a termination codon at position 361 and caused nonsense-mediated mRNA decay and lost the function. Our finding expands the genetic etiology spectrum of LP.

[The value of chromosomal microarray analysis and fluorescence in situ hybridization for the prenatal diagnosis of chromosomal mosaicisms].

OBJECTIVE: To assess the value of chromosomal microarray analysis (CMA) and fluorescence in situ hybridization (FISH) for the prenatal diagnosis of chromosomal mosaicisms. METHODS: A total of 775 pregnant women who had visited the Prenatal Diagnosis Center of Yancheng Maternal and Child Health Care Hospital from January 2018 to December 2020 were selected as study subjects. Chromosome karyotyping analysis and CMA were carried out for all women, and FISH was used to validate the suspected mosaicism cases. RESULTS: Among the 775 amniotic fluid samples, karyotyping has identified 13 mosaicism cases, which yielded a detection rate of 1.55%. Respectively, there were 4, 3, 4 and 2 cases for sex chromosome number mosaicisms, abnormal sex chromosome structure mosaicisms, abnormal autosomal number mosaicisms and abnormal autosomal structure mosaicisms. CMA has only detected only 6 of the 13 cases. Among 3 cases verified by FISH, 2 cases were consistent with the karyotyping and CMA results, and clearly showed low proportion mosaicism, and 1 case was consistent with the result of karyotyping but with a normal result by CMA. Eight pregnant women had chosen to terminate the pregnancy (5 with sex chromosome mosaicisms and 3 with autosomal mosaicisms). CONCLUSION: For fetuses suspected for chromosomal mosaicisms, CMA, FISH and G-banding karyotyping should be combined to determine the type and proportion of mosaicisms more precisely in order to provide more information for genetic counseling.

Expression of BmDHFR is up-regulated to trigger an increase in the BH4/BH2 ratio when the de novo synthesis of BH4 is blocked in silkworm, Bombyx mori.

Tetrahydrobiopterin (BH4) is a vital coenzyme for several enzymes involved in diverse enzymatic reactions in animals. BH4 deficiency can lead to metabolic and neurological disorders due to dysfunction in its metabolism. Sepiapterin reductase (SPR) and dihydrofolate reductase (DHFR) are crucial enzymes in the BH4 de novo synthesis pathway and salvage pathway, respectively. Dihydrobiopterin (BH2) is an oxidized product of BH4 metabolism. The ratio of BH4/BH2 is a key indicator of the stability of BH4 levels. The de novo pathway of BH4 synthesis is well-defined; however, little is known about the mechanisms of the salvage pathway in insects. Herein, we used the natural BmSPR mutant silkworm (lem) as a resource material. Our results reveal that the BmDHFR expression and the BH4/BH2 ratio were remarkably higher in lem as compared to the wild-type silkworm. In BmN cells, knockdown of BmSpr showed increased BmDHFR expression, while the BH4/BH2 ratio decreased after BmDhfr knockdown by RNAi. Furthermore, simultaneous RNAi of BmSpr and BmDhfr showed a further decrease in the BH4/BH2 ratio. These manifest that the expression of BmDHFR is up-regulated to trigger an increase in the BH4/BH2 ratio when the de novo synthesis of BH4 is blocked in silkworm. Additionally, the knockdown of BmSpr in wild-type silkworms also showed an increased BmDHFR level and BH4/BH2 ratio. Taken together, when the silkworm BH4 de novo synthesis pathway is blocked, the salvage pathway is activated, and BmDHFR plays an important role in maintaining the metabolic balance of silkworm BH4. This study enriches our understanding of the molecular mechanism of the BH4 salvage pathway and lays a good foundation for further studies on BH4 using the silkworm as a model insect.

Effects of Cigarette Smoke Exposure on the Gut Microbiota and Liver Transcriptome in Mice Reveal Gut-Liver Interactions.

Cigarette smoke exposure has a harmful impact on health and increases the risk of disease. However, studies on cigarette-smoke-induced adverse effects from the perspective of the gut-liver axis are lacking. In this study, we evaluated the adverse effects of cigarette smoke exposure on mice through physiological, biochemical, and histopathological analyses and explored cigarette-smoke-induced gut microbiota imbalance and changes in liver gene expression through a multiomics analysis. We demonstrated that cigarette smoke exposure caused abnormal physiological indices (including reduced body weight, blood lipids, and food intake) in mice, which also triggered liver injury and induced disorders of the gut microbiota and liver transcriptome (especially lipid metabolism). A significant correlation between intestinal bacterial abundance and the expression of lipid-metabolism-related genes was detected, suggesting the coordinated regulation of lipid metabolism by gut microbiota and liver metabolism. Specifically, Salmonella (harmful bacterium) was negatively and positively correlated with up- (such as Acsl3 and Me1) and downregulated genes (such as Angptl4, Cyp4a12a, and Plin5) involved in lipid metabolism, while Ligilactobacillus (beneficial bacterium) showed opposite trends with these genes. Our results clarified the key role of gut microbiota in liver damage and metabolism and improved the understanding of gut-liver interactions caused by cigarette smoke exposure.

Exploring the Mystery of the Tetrahydrobiopterin Synthetic Defect Lethal Mutant leml from Birth to Death in the Silkworm Bombyx mori.

Tetrahydrobiopterin (BH4) is a vital coenzyme for several enzymes involved in diverse enzymatic reactions in animals, and BH4 deficiency can lead to metabolic and neurological disorders due to dysfunction in its metabolism. In the silkworm natural homozygous mutant leml, the key enzyme sepiapterin reductase (BmSPR) in the de novo synthesis pathway of BH4 is inactivated, resulting in severe deficiency of BH4 synthesis. However, it is not known why the leml larvae can survive to the second-instar stage and which pathways lead to their death when BH4 is deficient. Here, we quantified BH4 and found that the fertilized eggs contained large amounts of BH4 transferred from the mother to the offspring, maintaining its normal development in the embryo and the first instar. Subsequently, we investigated the multiple pathways in which BH4 is involved as a cofactor. The results showed that BH4 deficiency in silkworms blocked the melanin synthesis pathway, caused an insufficient degree of epidermal sclerosis, disordered tyrosine metabolism, and damaged mitochondria. On the other hand, BH4 deficiency led to the uncoupling of nitric oxide synthase (BmNOS), a reduced NO production, and a significantly reduced fat in fat body catalyzation by phospholipase A2, resulting in an impaired immune system. Meanwhile, the uncoupling of BmNOS increased the O2- content, damaged the DNA, and caused the apoptosis of the body cells. Taken together, BH4 is critical for the life and death of leml mutants. This study lays a foundation for the further exploration of lepidopteran insects and provides an important basis for the treatment of human BH4 deficiency-related diseases.

Interspecies Metabolic Interactions in a Synergistic Consortium Drive Efficient Degradation of the Herbicide Bromoxynil Octanoate.

Microbial communities play vital roles in biogeochemical cycles, allowing biodegradation of a wide range of pollutants. Although many studies have shown the importance of interspecies interactions on activities of communities, fully elucidating the complex interactions in microbial communities is still challenging. Here, we isolated a consortium containing two bacterial strains (Acinetobacter sp. AG3 and Bacillus sp. R45), which could mineralize bromoxynil octanoate (BO) with higher efficiency than either strain individually. The BO degradation pathway by the synergistic consortium was elucidated, and interspecies interactions in the consortium were explored using genome-scale metabolic models (GSMMs). Modeling showed that growth and degradation enhancements were driven by metabolic interactions, such as syntrophic exchanges of small metabolites in the consortium. Besides, nutritional enhancers were predicted to improve BO degradation, which were tested experimentally. Overall, our results will enhance our understanding of microbial mineralization of BO by consortia and promote the application of microbial communities for bioremediation.

Efficacy and safety of retention enema with traditional Chinese medicine for ulcerative colitis: A meta-analysis of randomized controlled trials.

OBJECTIVE: To assess the efficacy and safety of retention enema with traditional Chinese medicine (TCM) for ulcerative colitis (UC) through a meta-analysis of published studies. METHODS: Literatures were retrieved from five electronic databases. Quality evaluation and meta-analysis were respectively conducted using the Cochrane collaboration and RevMan5.3. Overall quality of evidence was evaluated using GRADE system. Effect sizes were pooled using random effect models. RESULTS: Seventeen RCTs were included. Compared with routine pharmacotherapies (RPs), TCM enema exhibited a statistically significant difference in clinical efficacy and reduction of the recurrence rate. The results of qualitative description for other endpoints, such as improvements in anabrosis, ulcer, diarrhea, and hematochezia, suggested that TCM enema had better efficacy than RPs. Furthermore, the incidence of side effects in TCM was lower than that in RPs. CONCLUSION: This meta-analysis confirmed the efficacy and safety of TCM enema for improving UC symptoms. However, further well-designed researches are needed.

Responsive Photonic Crystal Microcapsules of Block Copolymers with Enhanced Monochromaticity.

Self-assembly of block copolymers (BCPs) has been developed as a promising approach for constructing photonic crystal (PC) microspheres for dynamic optical modulation. However, high curvature in the center of microspheres usually distorts the periodic core structure, leading to an inconsistency of photonic bandgap and poor monochromaticity of structural color. Herein, we report a simple yet robust strategy for fabricating responsive PC microcapsules of polystyrene-b-poly(2-vinylpyridine) through self-emulsification strategy. Interestingly, the microcapsules exhibit bright structural color with significantly enhanced monochromaticity, compared to their solid counterpart, since the microcapsules have no irregular cores. The structural colors of the PC microcapsules not only exhibit a variability through binary mixing of BCPs but also show a responsiveness to pH value. As a colored microcarrier, the PC microcapsules show a potential for visualizing the pH-dependent release behavior of encapsulated hydrophilic cargos on account of pH-responsive structural color.

Effect of hot water treatment on chilling injury and lignification of cold-stored fresh areca nut (Areca catechu L.).

Fresh areca nut is widely favored by consumers in South and Southeast Asia. However, postharvest areca nut perished quickly and was vulnerable to chilling injury (CI) and lignification during traditional cold storage. In order to alleviate this situation, hot water treatment was applied to investigate its effect on CI and lignification of fresh areca nut during cold storage at 13 °C. Areca nuts were submersed in hot water at 45 °C (HW45) and 50 °C (HW50) for short-term 5 min compared to fruit submersed in water at 20 °C (CT), then stored at 13 °C with 90% humidity for 60 days. CI, malondialdehyde (MDA), electrolyte leakage (EL), lignin and total phenolic content, related enzymes including phenylalanine ammonia-lyase (PAL), cinnamyl alcohol dehydrogenase (CAD) and peroxidase activity (POD) were examined. Results indicated that two HW treatments both induced chilling tolerance and delayed lignification of areca nut to varying degrees during cold storage compared with the CT. Among which, HW45 treated-areca nuts had the lowest CI, MDA content and EL while maintaining the highest total phenolic content. Moreover, no significant effects were found between HW45 and HW50 on tissue lignification, but they both effectively blocked lignin accumulation by inhibiting PAL, CAD and POD activities compared with the CT. The present study provided a safe physical method to mitigate CI and delay tissue lignification in cold-stored areca nut.

Functional characterization and regulatory mechanism of wheat CPK34 kinase in response to drought stress.

BACKGROUND: Drought is one of the most adverse environmental factors limiting crop productions and it is important to identify key genetic determinants for food safety. Calcium-dependent protein kinases (CPKs) are known to be involved in plant growth, development, and environmental stresses. However, biological functions and regulatory mechanisms of many plant CPKs have not been explored. In our previous study, abundance of the wheat CPK34 (TaCPK34) protein was remarkably upregulated in wheat plants suffering from drought stress, inferring that it could be involved in this stress. Therefore, here we further detected its function and mechanism in response to drought stress. RESULTS: Transcripts of the TaCPK34 gene were significantly induced after PEG-stimulated water deficiency (20% PEG6000) or 100 µM abscisic acid (ABA) treatments. The TaCPK34 gene was transiently silenced in wheat genome by using barley stripe mosaic virus-induced silencing (BSMV-VIGS) method. After 14 days of drought stress, the transiently TaCPK34-silenced wheat seedlings showed more sensitivity compared with control, and the plant biomasses and relative water contents significantly decreased, whereas soluble sugar and MDA contents increased. The iTRAQ-based quantitative proteomics was employed to measure the protein expression profiles in leaves of the transiently TaCPK34-silenced wheat plants after drought stress. There were 6103 proteins identified, of these, 51 proteins exhibited significantly altered abundance, they were involved in diverse function. And sequence analysis on the promoters of genes, which encoded the above identified proteins, indicated that some promoters harbored some ABA-responsive elements. We determined the interactions between TaCPK34 and three identified proteins by using bimolecular fluorescent complementation (BiFC) method and our data indicated that TaCPK34directly interacted with the glutathione S-transferase 1 and prx113, respectively. CONCLUSIONS: Our study suggested that the TaCPK34 gene played positive roles in wheat response to drought stress through directly or indirectly regulating the expression of ABA-dependent manner genes, which were encoding identified proteins from iTRAQ-based quantitative proteomics. And it could be used as one potential gene to develop crop cultivars with improved drought tolerance.