Environmental specificity of karst cave habitats evidenced by diverse symbiotic bacteria in Opiliones.

BACKGROUND: Karst caves serve as natural laboratories, providing organisms with extreme and constant conditions that promote isolation, resulting in a genetic relationship and living environment that is significantly different from those outside the cave. However, research on cave creatures, especially Opiliones, remains scarce, with most studies focused on water, soil, and cave sediments. RESULTS: The structure of symbiotic bacteria in different caves were compared, revealing significant differences. Based on the alpha and beta diversity, symbiotic bacteria abundance and diversity in the cave were similar, but the structure of symbiotic bacteria differed inside and outside the cave. Microorganisms in the cave play an important role in material cycling and energy flow, particularly in the nitrogen cycle. Although microbial diversity varies inside and outside the cave, Opiliones in Beijing caves and Hainan Island exhibited a strong similarity, indicating that the two environments share commonalities. CONCLUSIONS: The karst cave environment possesses high microbial diversity and there are noticeable differences among different caves. Different habitats lead to significant differences in the symbiotic bacteria in Opiliones inside and outside the cave, and cave microorganisms have made efforts to adapt to extreme environments. The similarity in symbiotic bacteria community structure suggests a potential similarity in host environments, providing an explanation for the appearance of Sinonychia martensi in caves in the north.

Diversity and Functionality of Bacteria Associated with Different Tissues of Spider Heteropoda venatoria Revealed through Integration of High-Throughput Sequencing and Culturomics Approaches.

Spiders host a diverse range of bacteria in their guts and other tissues, which have been found to play a significant role in their fitness. This study aimed to investigate the community diversity and functional characteristics of spider-associated bacteria in four tissues of Heteropoda venatoria using HTS of the 16S rRNA gene and culturomics technologies, as well as the functional verification of the isolated strains. The results of HTS showed that the spider-associated bacteria in different tissues belonged to 34 phyla, 72 classes, 170 orders, 277 families, and 458 genera. Bacillus was found to be the most abundant bacteria in the venom gland, silk gland, and ovary, while Stenotrophomonas, Acinetobacter, and Sphingomonas were dominant in the gut microbiota. Based on the amplicon sequencing results, 21 distinct cultivation conditions were developed using culturomics to isolate bacteria from the ovary, gut, venom gland, and silk gland. A total of 119 bacterial strains, representing 4 phyla and 25 genera, with Bacillus and Serratia as the dominant genera, were isolated. Five strains exhibited high efficiency in degrading pesticides in the in vitro experiments. Out of the 119 isolates, 28 exhibited antibacterial activity against at least one of the tested bacterial strains, including the pathogenic bacteria Staphylococcus aureus, Acinetobacter baumanii, and Enterococcus faecalis. The study also identified three strains, GL312, PL211, and PL316, which exhibited significant cytotoxicity against MGC-803. The crude extract from the fermentation broth of strain PL316 was found to effectively induce apoptosis in MGC-803 cells. Overall, this study offers a comprehensive understanding of the bacterial community structure associated with H. venatoria. It also provides valuable insights into discovering novel antitumor natural products for gastric cancer and xenobiotic-degrading bacteria of spiders.

Research on complex network modeling of building materials supply and demand and characteristics of communities.

Currently, China's building materials market is large and the supply and demand transactions are very frequent, which requires us to have a comprehensive understanding of the supply and demand transactions of building materials. Based on complex network theory, this paper constructs a complex network model of supply and demand of building materials. And the Louvain algorithm is also improved to identify and characterize the network community relations based on the characteristics of this network. This paper also applies prefabricated components as an example for empirical research and obtains the following findings: (1) From 2017 to 2022, large- and medium-sized communities in the network gradually increase while small communities gradually decrease; the internal connectivity of large communities is higher than that of small communities; and the regional network also has the structural characteristics of the network. (2) The characteristics of geographic agglomeration gradually emerge in the individual communities in the supply-demand network of prefabricated components with the passage of time. Most of these communities are bounded by provinces, and large-scale communities are distributed in the eastern and southern coastal areas. Thus, this paper visualizes the supply and demand of construction materials to provide a theoretical basis and methodological support for the supply and demand of construction materials and the development of the construction industry.

Excess Mortality for Femoral Intertrochanteric Fracture Patients Aged 50 Years and Older Treated Surgically and Conservatively in Tianjin, China: A Cohort Study.

OBJECTIVE: Intertrochanteric fracture is one type of hip fracture, which is the most serious consequence of osteoporosis. Along with the growing elderly population, intertrochanteric fracture is expected to rise increasingly. The aim of this study was to assess excess mortality after intertrochanteric fractures and to identify the predictors of long-term mortality by therapy among patients aged 50 years and older in Tianjin. METHODS: This is a retrospective cohort study on mortality for 3029 patients aged 50 years and older in Tianjin experiencing an intertrochanteric fracture between December 26, 2014 and December 31, 2018. Data were from Tianjin Hospital Hip Fracture (THHF) cohort. Follow-up period was until March 31, 2022. Mortality, excess mortality, and comorbidities were analyzed and stratified by therapy and gender. Time dependent Cox models were performed to estimate the effects of the variables. RESULTS: Absolute mortality for all the patients was 5.90% at 3 months, 12.55% at 12 months, 19.92% at 24 months and 27.28% at 36 months. Absolute mortality for surgical group was 1.57% at 3 months, 4.77% at 12 months, 8.49% at 24 months and 12.07% at 36 months, significantly lower than conservative group: 10.50% at 3 months, 20.73% at 12 months, 31.96% at 24 months and 43.04% at 36 months. We found a substantially lower mortality (hazard ratio [HR] 0.34, 95% confidence internal, [CI]: 0.23-0.52, p = 0.000) among patients undergoing surgical therapy than those undergoing conservative therapy, even when controlled for gender, age, the length of hospital stay, and all the comorbidities. Female patients (HR 0.68, 95% CI: 0.58-0.79, p = 0.000) were less likely to die than male patients after an intertrochanteric fracture. Patients treated by the two methods were both found to have excess mortality rates compared to the general population, although in different levels. The excess mortality rates for patients in the conservative therapy group were 14.46% in males and 17.93% in females, while in the surgical therapy group, 2.78% in females and 4.37% in males. The comorbidities moderate or severe renal disease (HR 2.19, 95% CI: 1.61-2.98, p = 0.000), metastatic solid tumor (HR 6.35, 95% CI: 1.56-25.85, p = 0.010), hypoproteinemia (HR 1.22, 95% CI: 1.01-1.47, p = 0.034), and older age (HR 1.89, 95% CI: 1.73-2.08, p = 0.000) were also risk factors on mortality. A worse-case analysis for the primary outcome were performed as sensitivity analysis and it was consistent with the original conclusion. CONCLUSION: Intertrochanteric factures for people aged 50 years older were found to have excess mortality compared to the general population in Tianjin city, and preventing the fractures in the hip for elderly people was imperative. After controlling tfor comorbidities and age, female gender and surgical therapy were protective factors for the death after fractures, which could provide strong evidence for patients and surgeons to make decisions.

Coffee-Associated Endophytes: Plant Growth Promotion and Crop Protection.

Endophytic microbes are a ubiquitous group of plant-associated communities that colonize the intercellular or intracellular host tissues while providing numerous beneficial effects to the plants. All the plant species are thought to be associated with endophytes, majorly constituted with bacteria and fungi. During the last two decades, there has been a considerable movement toward the study of endophytes associated with coffee plants. In this review, the main consideration is given to address the coffee-associated endophytic bacteria and fungi, particularly their action on plant growth promotion and the biocontrol of pests. In addition, we sought to identify and analyze the gaps in the available research. Additionally, the potential of endophytes to improve the quality of coffee seeds is briefly discussed. Even though there are limited studies on the subject, the potentiality of coffee endophytes in plant growth promotion through enhancing nitrogen fixation, availability of minerals, nutrient absorption, secretion of phytohormones, and other bioactive metabolites has been well recognized. Further, the antagonistic effect against various coffee pathogenic bacteria, fungi, nematodes, and also insect pests leads to the protection of the crop. Furthermore, it is recognized that endophytes enhance the sensory characteristics of coffee as a new field of study.

Propylene glycol-mixed steam enhanced extraction for an efficient and sustainable remediation of PAHs-contaminated soil.

An innovative thermal desorption method, propylene glycol (PG)-mixed steam enhanced extraction, is proposed for a highly efficient remediation of polycyclic aromatic hydrocarbons (PAHs)-contaminated soil. It is found that injecting PG-mixed steam into soil column could obtain > 99% removal efficiencies of PAHs either for the pyrene-spiked soil, or for the contaminated field soil with high-molecular-weight PAHs. PG is a safe and low-cost dihydric alcohol with a boiling point higher than water. When the PG-mixed steam penetrated the contaminated soil, the PG vapor preferentially condensed to form a hot liquid with concentrated PG (e.g., from 30 wt% PG in gas phase to 90 wt% PG in the liquid phase), which would significantly solubilize the PAHs and enhance their desorption from soils. The results also revealed that the effluents derived from the PG-mixed steam could be purified by removing the desorbed PAHs using a simple coagulation treatment, and the recovered PG solution could be reused. The plant assay using wheat seeds showed that the remediated soil had a good regreening potential. Our results demonstrate that PG-mixed steam injection is a promising thermal desorption method for an efficient and sustainable remediation of PAHs-contaminated soil.

Echolocation clicks of free-ranging Indo-Pacific finless porpoises (Neophocaena phocaenoides) in Hainan waters.

The echolocation clicks of free-ranging Indo-Pacific finless porpoises (IPFPs, Neophocaena phocaenoides) have been rarely studied in the wild. This paper aims at describing the echolocation-click characteristics of IPFPs and examining whether IPFPs adapt their sonar system to the habitats in Hainan waters, China. The echolocation clicks were recorded using a 13 elements star-shaped array of hydrophones. A total of 65 on-axis clicks were identified and analyzed. IPFPs use echolocation clicks with a source level (SL) of 158 ± 9 dB re: 1 µPa peak-peak, mean peak, and centroid frequency of 134 ± 3 kHz, -3 dB bandwidth of 14 ± 2 kHz and produce at inter-click intervals of 104 ± 51 ms. The results relative to other porpoises show that finless porpoises in Hainan waters produce clicks with moderate SLs and high peak frequency. These results could be useful in detecting the presence and estimating the density of IPFPs during passive acoustic monitoring in the study area and serve to shed light on the interpopulation variation of click characteristics of finless porpoises as well.

Spatiotemporal evolution law and output prediction of construction waste in the People's Republic of China.

Based on the relevant data of construction waste (CW) in the People's Republic of China (PRC) from 2010 to 2018, this study applied K-means clustering algorithm and grey prediction methods to systematically investigate the spatiotemporal characteristic distribution and provincial clustering of CW in the PRC, and predicted the annual output of CW in the next five years from the scientific perspective. Results showed that the annual output of CW in the PRC displayed an overall trend of "rising first and then falling" and "being high in the middle east and low in the northwest," and the areas with obvious agglomeration gradually spread from the west to the middle and eastern regions. The law of development was consistent with the goals of the Chinese government to promulgate urban agglomeration development policies, prefabricated building encouragement policies, and CW management regulations. In the next five years, the annual output of CW in the PRC will increase by a small margin. Thus, all aspects of CW resource management should be conducted in a planned and step-by-step manner.

Bispecific antibody targeting TROP2xCD3 suppresses tumor growth of triple negative breast cancer.

BACKGROUND: Triple negative breast cancer (TNBC) is a subtype of breast cancers with poor prognosis and targeted drug therapies are limited. To develop novel and efficacious therapies for TNBC, we developed a bispecific antibody F7AK3 that recognizes both trophoblast cell surface antigen 2 (TROP2) and CD3 and evaluated its antitumor activities both in vitro and in vivo. METHODS: The binding affinities of F7AK3 to the two targets, TROP2 and CD3, were evaluated by surface plasmon resonance. Binding of F7AK3 to TNBC cells and T cells were evaluated by flow cytometry. Immunofluorescent staining was performed to demonstrate the interactions between T cells with TNBC cells. The cytotoxicity of T cells against TNBC cell lines and primary tumor cells mediated by F7AK3 were determined in vitro. In vivo antitumor activity of F7AK3 was investigated in a xenograft TNBC tumor model, using immunodeficient mice that were reconstituted with human peripheral blood mononuclear cells. RESULTS: We demonstrated that F7AK3 binds specifically to human TROP2 and CD3 antigens, as well as TNBC cell lines and primary tumor cells. Human T cells can only be activated by F7AK3 in the presence of target tumor cells. F7AK3 recruits T cells to TROP2+ tumor cells in vitro and into tumor tissues in vivo. Antitumor growth activity of F7AK3 is observed in a xenograft TNBC tumor model. CONCLUSION: This study showed the antitumor potential of an anti-TROP2xCD3 bispecific antibody F7AK3 to TNBC tumor cells both in vitro and in vivo. These data demonstrate that F7AK3 has the potential to treat TNBC patients, which warrants further preclinical and clinical evaluation of the F7AK3 in advanced or metastatic TNBC patients.

Temporal variation of the underwater soundscape in Jiaotou Bay, an Indo-Pacific humpback dolphin (Sousa chinensis) habitat off Hainan Island, China.

The underwater soundscape is an important ecological element affecting numerous aquatic animals, in particular dolphins, which must identify salient cues from ambient ocean noise. In this study, temporal variations in the soundscape of Jiaotou Bay were monitored from February 2016 to January 2017, where a population of Indo-Pacific humpback dolphins (Sousa chinensis) has recently been a regular sighting. An autonomous acoustic recorder was deployed in shallow waters, and 1/3-octave band sound pressure levels (SPLs) were calculated with central frequencies ranging from 25 Hz to 40 kHz, then were grouped into 3 subdivided bands via cluster analysis. SPLs at each major band showed significant differences on a diel, fishing-related period, seasonal, and tidal phase scale. Anthropogenic noise generated by passing ships and underwater explosions were recorded in the study area. The fish and dolphin acoustic activities both exhibited diel and seasonal variations, but no tidal cycle patterns. A negative significant relationship between anthropogenic sound detection rates and dolphin detection rates were observed, and fish detection rates showed no effect on dolphin detection rates, indicating anthropogenic activity avoidance and no forced foraging in dolphins in the study area. The results provide fundamental insight into the acoustic dynamics of an important Indo-Pacific humpback dolphin habitat within a coastal area affected by a rapid increase in human activity, and demonstrate the need to protect animal habitat from anthropogenic noises.

Blood biomarkers related to osteonecrosis of femoral head by internal fixation after Garden I femoral neck fracture: a cohort study.

BACKGROUND: Internal fixation is currently considered the gold standard in treatment for femoral neck fractures in adults. However, osteonecrosis of the femoral head (ONFH) after internal fixation would occur in quite proportion of patients with femoral neck fracture, even in Garden I femoral neck fracture. The purpose of this study was to determine the association between the blood biomarkers (serum albumin, pre-albumin, total protein and total lymphocyte count) and ONFH following internal fixation of Garden I femoral neck fracture in adults. METHOD: This is a single center cohort study, in which each patient who sustained a Garden I femoral neck fracture had been treated with internal fixation, and had adequate preoperative blood examinations. The serum albumin was categorized as ≥ 40g/L or < 40g/L. The pre-albumin was categorized as ≥ 22mg/dL or < 22mg/dL. The total protein was categorized as ≥ 65g/L or < 65 g/L. The total lymphocyte count was categorized as ≥1.1× 109 /L or <1.1×109 /L. Multivariate cox proportional hazards analysis was used to assess the association between blood markers and the osteonecrosis of femoral head during the 2-years follow-up period controlling the confounders. RESULT: A total of 10 cases of ONFH were identified. Multivariate Cox regression analysis revealed that low total lymphocyte count and hypertension state were significant independent risk factors for ONFH after internal fixation for Garden I femoral head fractures. CONCLUSION: Blood biomarkers were potential predictors for ONFH after internal fixation Garden I femoral neck fractures. We suggest that routine laboratory tests might can be used to assist surgeons to identify patients at great risk of ONFH.

Modulation of p53 N-terminal transactivation domain 2 conformation ensemble and kinetics by phosphorylation.

Phosphorylation of protein is critical for various cell processes, which preferentially happens in intrinsically disordered proteins (IDPs). How phosphorylation modulates structural ensemble of disordered peptide remains largely unexplored. Here, using replica exchange molecular dynamics (REMD) and Markov state model (MSM), the conformational distribution and kinetics of p53 N-terminal transactivation domain (TAD) 2 as well as its dual-site phosphorylated form (pSer46, pThr55) were simulated. It reveals that the dual phosphorylation does not change overall size and secondary structure element fraction, while a change in the distribution of hydrogen bonds induces slightly more pre-existing bound helical conformations. MSM analysis indicates that the dual phosphorylation accelerates conformation exchange between disordered and order-like states in target-binding region. It suggests that p53 TAD2 after phosphorylation would be more apt to bind to both the human p62 pleckstrin homology (PH) domain and the yeast tfb1 PH domain through different binding mechanism, where experimentally it exhibits an extended and α-helix conformation, respectively, with increased binding strength in both complexes. Our study implies except binding interface, both conformation ensemble and kinetics should be considered for the effects of phosphorylation on IDPs. AbbreviationsIDPsintrinsically disordered proteinsREMDreplica exchange molecular dynamicsMSMMarkov state modelTADtransactivation domainPHpleckstrin homologyPRRproline-rich regionDBDDNA-binding domainTETTetramerization domainREGregulatory domainMDmolecular dynamicsPMEparticle-mesh EwaldTICAtime-lagged independent component analysisCKChapman-KolmogorovGMRQgeneralized matrix Rayleigh quotientSARWself-avoiding random walkKIDkinase-inducible domainMFPTmean first passage timeDSSPdefinition of secondary structure of proteinsRMSDroot mean square deviationRgradius of gyrationReeend to end distanceCommunicated by Ramaswamy H. Sarma.

How calcium ion binding induces the conformational transition of the calmodulin N-terminal domain-an atomic level characterization.

Allostery plays important roles in the regulation of many biological processes, such as signal transduction and transcriptional regulation. Although great advances have been achieved in understanding the allosteric mechanism through experimental and theoretical investigations, the details of the allosteric process are still not clear. Here, using the N-terminal domain of calmodulin (nCaM) as the model protein, we reported the atomic level characterization of the allosteric process induced by Ca2+ binding through extensive and unbiased molecular dynamics simulations. In two trajectories, it was found that Ca2+ first binds to EF-hand 2 and then induces the conformational transformation of nCaM from the Apo to Holo state assisted by second Ca2+ binding to EF-hand 1 completely. The binding order was consistent with a recent experimental result. The simulations also indicated that the two EF-hands changed conformations synergistically and the EF-hand 2 showed an earlier and more gradual conformational transition. Meanwhile, the allosteric process of nCaM triggered by Ca2+ binding might be completed within hundreds of nanoseconds in a two-state-like manner. This was validated by biased simulations, in which the Ca2+ ions were restrained near the binding sites. This work provides the molecular details of the conformational transition of nCaM triggered by Ca2+ binding.

Integration of T7 exonuclease-triggered amplification and cationic conjugated polymer biosensing for highly sensitive detection of microRNA.

A novel and highly sensitive method for detection of microRNA (miRNA) was developed by integration of T7 exonuclease-triggered amplification and cationic conjugated polymer (CCP) biosensing. First, a fluorescein-labeled probe was designed with the complementary sequence to the target miRNA. When target miRNA was absent in the solution, the fluorescence probe interacted with CCP through the strong electrostatic interactions, leading to the highly efficient fluorescence resonance energy transfer (FRET) from CCP to fluorescein. In the presence of target miRNA, the probe hybridized with the miRNA to form DNA/miRNA duplex hybrids. Then, T7 exonuclease digested cyclically the fluorescence probes in hybrids and triggered the enzyme amplification reaction, generating a large number of single nucleotides. Owing to the weak electrostatic interaction between CCP and the single nucleotide, the FRET from CCP to fluorescein would not take place, which effectively reduced the background and significantly enhanced the sensitivity and the dynamic range of miRNA detection. The linear range of the assay was 0.2-100 pM and the detection limit 0.08 pM was 58 times lower than that of the endonuclease-based assay. The method is simple, cost-effective, and with no need for the sophisticated instrument, and has broad application prospects for miRNA detection and early diagnosis.

Using Naive Bayes Classifier to predict osteonecrosis of the femoral head with cannulated screw fixation.

Predictive models permitting personalized prognostication for patients with cannulated screw fixation for the femoral neck fracture before operation are lacking. The objective of this study was to train, test, and cross-validate a Naive Bayes Classifier to predict the occurrence of postoperative osteonecrosis of cannulated screw fixation before the patient underwent the operation. The data for the classifier model were obtained from a ambispective cohort of 120 patients who had undergone closed reduction and cannulated screw fixation from January 2011 to June 2013. Three spatial displaced parameters of femoral neck: displacement of centre of femoral head, displacement of deepest of femoral head foveae and rotational displacement were measured from preoperative CT scans using a 3-dimensional software. The Naive Bayes Classifier was modelled with age, gender, side of fractures, mechanism of injury, preoperative traction, Pauwels angle and the three spatial parameters. After modelling, the ten-fold cross-validation method was used in this study to validate its performance. The ten-fold cross-validation method uses the whole dataset to be trained and tested by the given algorithm. Two of the three spatial parameters of femoral neck (displacement of center of femoral head and rotational displacement) were included successfully in the final Naive Bayes Classifier. The Classifier achieved good performance of the accuracy (74.4%), sensitivity (74.2%), specificity (75%), positive predictive value (92%), negative predictive value (42.9%) and AUC (0.746). We showed that the Naive Bayes Classifier have the potential utility to be used to predict the osteonecrosis of femoral head within 5 years after surgery. Although this study population was restricted to patients treated with cannulated screws fixation, Bayesian-derived models may be developed for application to patients with other surgical procedures at risk of osteonecrosis.

Cladolasma ailaoshan, a new species of the genus Cladolasma Suzuki, 1963 from China (Opiliones, Nemastomatidae, Ortholasmatinae).

The fourth species of the Asian genus Cladolasma, C. ailaoshansp. n. is described from specimens collected in Yunnan Province, China. The new species is distinct from C. parvulum Suzuki, 1963 and C. angka (Schwendinger & Gruber, 1992) in lacking enlarged, dorsally-directed tubercles on the abdominal scutum; and from C. damingshan Zhang & Zhang, 2013 in having keels around the eyes and in the position of the eyes. Differences in male genital structures between the Chinese species are small, while there are more differences with the Japanese species.

Characterization of the structural ensembles of p53 TAD2 by molecular dynamics simulations with different force fields.

Intrinsically disordered regions (IDRs) or proteins (IDPs), which play crucial biological functions in essential biological processes of life, do not have well-defined secondary or tertiary structures when isolated in solution. The highly dynamic properties and conformational heterogeneity of IDPs make them challenging to study with traditional experimental techniques. As a powerful complementary tool for experiments, all-atom molecular dynamics simulation can obtain detailed conformational information on IDPs, but the limitation of force field accuracy is a challenge for reproducing IDP conformers. Here, we compared five empirical all-atom force fields AMBER03, AMBER99SB-ILDN, CHARMM27, OPLS-AA/L and CHARMM36m in modeling the conformational ensembles of wild-type peptide TAD2(41-62) from the human p53 tumor suppressor. Our results show that for the model peptide, the newest force field CHARMM36m produces more expanded coil ensemble followed by AMBER99SB-ILDN; CHARMM27 displays a predominant propensity for a helical structure; whereas OPLS-AA/L exhibits a apparent preference for a ß-sheet structure and yields the most compact conformation. In the comparison of the simulated dimensions with theoretical prediction and the back-calculated chemical shifts with experimental measurements, AMBER99SB-ILDN gives a more consistent agreement than the other force fields. In addition, the region from residues 47 to 55, which commonly forms an amphipathic α-helix upon binding target proteins according to experimental observation, could form a helical structure with a different probability population in our simulations with different force fields. This implies that the binding process might be conducted by, or partly by "conformation selection" for this peptide. This work indicates that force field development for modeling general IDPs accurately has a long way to go, and more detailed experimental data of IDPs are also in demand.

Agrobacterium tumefaciens-mediated transformation as an efficient tool for insertional mutagenesis of Cercospora zeae-maydis.

An efficient Agrobacterium tumefaciens-mediated transformation (ATMT) approach was developed for the plant pathogenic fungus, Cercospora zeae-maydis, which is the causative agent of gray leaf spot in maize. The transformation was evaluated with five parameters to test the efficiencies of transformation. Results showed that spore germination time, co-cultivation temperature and time were the significant influencing factors in all parameters. Randomly selected transformants were confirmed and the transformants were found to be mitotically stable, with single-copy T-DNA integration in the genome. T-DNA flanking sequences were cloned by thermal asymmetric interlaced PCR. Thus, the ATMT approach is an efficient tool for insertional mutagenesis of C. zeae-maydis.

Conjugated Polymers/DNA Hybrid Materials for Protein Inactivation.

Chromophore-assisted light inactivation (CALI) is a powerful tool for analyzing protein functions due to the high degree of spatial and temporal resolution. In this work, we demonstrate a CALI approach based on conjugated polymers (CPs)/DNA hybrid material for protein inactivation. The target protein is conjugated with single-stranded DNA in advance. Single-stranded DNA can form CPs/DNA hybrid material with cationic CPs via electrostatic and hydrophobic interactions. Through the formation of CPs/DNA hybrid material, the target protein that is conjugated with DNA is brought into close proximity to CPs. Under irradiation, CPs harvest light and generate reactive oxygen species (ROS), resulting in the inactivation of the adjacent target protein. This approach can efficiently inactivate any target protein which is conjugated with DNA and has good specificity and universality, providing a new strategy for studies of protein function and adjustment of protein activity.

A simple molecular beacon with duplex-specific nuclease amplification for detection of microRNA.

MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene activity, promoting or inhibiting cell proliferation, migration and apoptosis. Abnormal expression of miRNAs is associated with many diseases. Therefore, it is essential to establish a simple, rapid and sensitive miRNA detection method. In this paper, based on a simple molecular beacon (MB) and duplex-specific nuclease (DSN), we developed a target recycling amplification method for miRNA detection. By controlling the number of stem bases to 5, the MB probe used in this method can be prevented from hydrolysis by DSN without special modification. This assay is direct and simple to quantitatively detect miRNA with high sensitivity and specificity. The MB probe design provides a new strategy for nuclease-based amplification reaction.