Apple SUMO E3 ligase MdSIZ1 regulates cuticular wax biosynthesis by SUMOylating transcription factor MdMYB30.

A key function of SUMOylation is the coordinated modification of numerous proteins to optimize plant growth and resistance to environmental stress. Plant cuticular wax is deposited on the surface of primary plant organs to form a barrier that provides protection against changes in terrestrial environments. Many recent studies have examined cuticular wax biosynthetic pathways and regulation. However, whether SUMOylation is involved in the regulation of cuticle wax deposition at the posttranslational level remains unclear. Here, we demonstrate that a small ubiquitin-like modifier (SUMO) E3 ligase, SAP AND MIZ1 DOMAIN CONTAINING LIGASE1 (MdSIZ1), regulates wax accumulation and cuticle permeability in apple (Malus domestica Borkh), SUMO E2 CONJUGATING ENZYME 1(MdSCE1) physically interacts with MdMYB30, a transcription factor involved in the regulation of cuticle wax accumulation. MdSIZ1 mediates the SUMOylation and accumulation of MdMYB30 by inhibiting its degradation through the 26S proteasome pathway. Furthermore, MdMYB30 directly binds to the ß-KETOACYL-COA SYNTHASE 1 (MdKCS1) promoter to activate its expression and promote wax biosynthesis. These findings indicate that the MdSIZ1-MdMYB30-MdKCS1 module positively regulates cuticular wax biosynthesis in apples. Overall, the findings of our study provide insights into the regulation pathways involved in cuticular wax biosynthesis.

Substituent Engineering in Pore-Space-Partitioned Metal-Organic Frameworks for CO2 Selective Adsorption and Fixation.

Comprehensive understanding of substituent groups located on the pore surface of metal-organic frameworks (which we call substituent engineering herein) can help to promote gas adsorption and catalytic performance through ligand functionalization. In this work, pore-space-partitioned metal-organic frameworks (PSP MOFs) were selected as a platform to evaluate the effect of organic functional groups on CO2 adsorption, separation, and catalytic conversion. Twelve partitioned acs metal-organic frameworks (pacs-MOFs, named SNNU-25-Rn here) containing different functional groups were synthesized, which can be classified into electron-donor groups (-OH, -NH2, -CH3, and -OCH3) and electron-acceptor groups (-NO2, -F, -Cl, and -Br). The experimental results showed that SNNU-25-Rn with electron donors usually perform better than those with electron acceptors for the comprehensive utilization of CO2. The CO2 uptake of the 12 SNNU-25-Rn MOFs ranged from 30.9 to 183.6 cm3 g-1 at 273 K and 1 bar, depending on the organic functional groups. In particular, SNNU-25-OH showed the highest CO2 adsorption, SNNU-25-CH3 had the highest IAST of CO2/CH4 (36.1), and SNNU-25-(OH)2 showed the best catalytic activity for the CO2 cycloaddition reaction. The -OH functionalized MOFs with excellent performance may be attributed to the Lewis acid-base and hydrogen-bonding interactions between -OH groups and the CO2 molecules. This work modulated the effect of the microenvironment of MOFs on CO2 adsorption, separation, and catalysis in terms of substituents, providing valuable information for the precise design of porous MOFs with a comprehensive utilization of CO2.

What affects the accuracy and applicability of determining wastewater sludge water content via low-field nuclear magnetic resonance?

The accurate determination of waster sludge water content is crucial to sludge dewatering treatment and its disposal management. Though previous studies highlight the great advantages of low-field nuclear magnetic resonance (LF-NMR) in the determination of sludge water content, its accuracy and applicability are not well studied. Herein, this study investigated the settling of operating parameters and the properties of sludge samples on the accuracy and applicability of LF-NMR method in measuring sludge water content. The results showed that the setting of basic parameters such as standard curve, number of scanning times (NS) and sample weight affected the accuracy of sludge water content by LF-NMR. The standard calibration curve constructed by 3 g/L CuSO4, NS = 8 and the sample weight of about 5 g, were suitable for the accurate determination of sludge water content. Furthermore, the existence of magnetic substances in sludge can affect the distribution gradient of main magnetic field, and thus restricted the applicability of LF-NMR. The saturation magnetization of chemical reagents strongly correlated with the measured relative errors of sludge water content (r = 0.995, p < 0.01), the greater the saturation magnetization of the magnetic material, the greater the error of the test results. On the whole, it is necessary to fully consider the influence of process parameters and sludge properties to evaluate the accuracy and applicability of the LF-NMR method, rather than simply copying the parameters in literatures.

Enhancing data reliability in quantitative characterization of moisture distribution in sludge using DSC: Impact of sample attributes and test parameters.

Exploring moisture distribution, especially bound water content, is vital for studying and applying sludge dewatering. The differential scanning calorimetry (DSC) method has been extensively utilized for the quantitative characterization of moisture distribution in sludge. However, this method has certain limitations, such as low reproducibility of results, leading to controversial parameter values in different papers and hindering result comparison. In this study, we investigated the influence of key sample attributes on measuring sludge bound water using the DSC method.The findings demonstrated that the moisture content and mass of sludge samples substantially influenced the reproducibility and stability of DSC test results. To ensure data reliability, the moisture content of the sludge sample should be minimized and kept below 84%, with the mass not exceeding 10 mg. Compared to the influence of sludge moisture content and sample mass, the heating rate (1⁓5 °C/min) minimally affected DSC test results. This study offers a comprehensive insight into how sample attributes and test parameters affect the quantitative characterization of bound water in sludge using the DSC method. Furthermore, practical strategies are presented to enhance the method's applicability in sludge bound water characterization.

[Variation and interaction mechanism between active components in Rheum officinale and rhizosphere soil microorganisms under drought stress].

To explore the changes and the reaction mechanisms between soil microecological environment and the content of secon-dary metabolites of plants under water deficit, this study carried out a pot experiment on the 3-leaf stage seedlings of Rheum officinale to analyze their response mechanism under different drought gradients(normal water supply, mild, moderate, and severe drought). The results indicated that the content of flavonoids, phenols, terpenoids, and alkaloids in the root of R. officinale varied greatly under drought stresses. Under mild drought stress, the content of substances mentioned above was comparatively high, and the content of rutin, emodin, gallic acid, and(+)-catechin hydrate in the root significantly increased. The content of rutin, emodin, and gallic acid under severe drought stress was significantly lower than that under normal water supply. The number of species, Shannon diversity index, richness index, and Simpson index of bacteria in the rhizosphere soil were significantly higher than those in blank soil, and the number of microbial species and richness index decreased significantly with the aggravation of drought stresses. In the context of water deficit, Cyanophyta, Firmicutes, Actinobacteria, Chloroflexi, Gemmatimonadetes, Streptomyces, and Actinomyces were the dominant bacteria in the rhizosphere of R. officinale. The relative content of rutin and emodin in the root of R. officinale was positively correlated with the relative abundance of Cyanophyta and Firmicutes, and the relative content of(+)-catechin hydrate and(-)-epicatechin gallate was positively correlated with the relative abundance of Bacteroidetes and Firmicutes. In conclusion, appropriate drought stress can increase the content of secondary metabolites of R. officinale from physiological induction and the increase in the association with beneficial microbe.

The energy cost of repairing photoinactivated photosystem II: an experimental determination in cotton leaf discs.

Photosystem II (PSII), which splits water molecules at minimal excess photochemical potential, is inevitably photoinactivated during photosynthesis, resulting in compromised photosynthetic efficiency unless it is repaired. The energy cost of PSII repair is currently uncertain, despite attempts to calculate it. We experimentally determined the energy cost of repairing each photoinactivated PSII in cotton (Gossypium hirsutum) leaves, which are capable of repairing PSII in darkness. As an upper limit, 24 000 adenosine triphosphate (ATP) molecules (including any guanosine triphosphate synthesized at the expense of ATP) were required to repair one entire PSII complex. Further, over a 7-h illumination period at 526-1953 µmol photons m-2 s-1 , the ATP requirement for PSII repair was on average up to 4.6% of the ATP required for the gross carbon assimilation. Each of these two measures of ATP requirement for PSII repair is two- to three-fold greater than the respective reported calculated value. Possible additional energy sinks in the PSII repair cycle are discussed.

Pharmacological inhibition of MyD88 suppresses inflammation in tubular epithelial cells and prevents diabetic nephropathy in experimental mice.

Emerging evidence shows that chronic inflammation mediated by toll-like receptors (TLRs) contributes to diabetic nephropathy. Myeloid differentiation primary-response protein-88 (MyD88) is an essential adapter protein of all TLRs except TLR3 in innate immunity. It is unclear whether MyD88 could be a therapeutic target for diabetic nephropathy. Here, we used a new small-molecule MyD88 inhibitor, LM8, to examine the pharmacological inhibition of MyD88 in protecting kidneys from inflammatory injury in diabetes. We showed that MyD88 was significantly activated in the kidney of STZ-induced type 1 diabetic mice in tubular epithelial cells as well as in high glucose-treated rat tubular epithelial cells NRK-52E. In cultured tubular epithelial cells, we show that LM8 (2.5-10 µM) or MyD88 siRNA attenuated high-concentration glucose-induced inflammatory and fibrogenic responses through inhibition of MyD88-TLR4 interaction and downstream NF-κB activation. Treatment with LM8 (5, 10 mg/kg, i.g.) significantly reduced renal inflammation and fibrosis and preserved renal function in both type 1 and type 2 diabetic mice. These renoprotective effects were associated with reduced MyD88-TLR4 complex formation, suppressed NF-κB signaling, and prevention of inflammatory factor expression. Collectively, our results show that hyperglycemia activates MyD88 signaling cascade to induce renal inflammation, fibrosis, and dysfunction. Pharmacological inhibition of MyD88 may be a therapeutic approach to mitigate diabetic nephropathy and the inhibitor LM8 could be a potential candidate for such therapy.

Chalcone derivatives ameliorate lipopolysaccharide-induced acute lung injury and inflammation by targeting MD2.

Acute lung injury (ALI) and its severe form acute respiratory distress syndrome (ARDS) are known as the common causes of respiratory failure in critically ill patients. Myeloid differentiation 2 (MD2), a co-receptor of toll like receptor 4 (TLR4), plays an important role in LPS-induced ALI in mice. Since MD2 inhibition by pharmacological inhibitors or gene knockout significantly attenuates ALI in animal models, MD2 has become an attractive target for the treatment of ALI. In this study we identified two chalcone-derived compounds, 7w and 7x, as new MD2 inhibitors, and investigated the therapeutic effects of 7x and 7w in LPS-induced ALI mouse model. In molecular docking analysis we found that 7w and 7x, formed pi-pi stacking interactions with Phe151 residue of the MD2 protein. The direct binding was confirmed by surface plasmon resonance analysis (with KD value of 96.2 and 31.2 µM, respectively) and by bis-ANS displacement assay. 7w and 7x (2.5, 10 µM) also dose-dependently inhibited the interaction between lipopolysaccharide (LPS) and rhMD2 and LPS-MD2-TLR4 complex formation. In mouse peritoneal macrophages, 7w and 7x (1.25-10 µM) dose-dependently inhibited LPS-induced inflammatory responses, MAPKs (JNK, ERK and P38) phosphorylation as well as NF-κB activation. Finally, oral administration of 7w or 7x (10 mg ·kg-1 per day, for 7 days prior LPS challenge) in ALI mouse model significantly alleviated LPS-induced lung injury, pulmonary edema, lung permeability, inflammatory cells infiltration, inflammatory cytokines expression and MD2/TLR4 complex formation. In summary, we identify 7w and 7x as new MD2 inhibitors to inhibit inflammatory response both in vitro and in vivo, proving the therapeutic potential of 7w and 7x for ALI and inflammatory diseases.

Competitive CatSper Activators of Progesterone from Rhynchosia volubilis.

The root Rhynchosia volubilis was widely used for contraception in folk medicine, although its molecular mechanism on antifertility has not yet been revealed. In human sperm, it was reported that the cation channel of sperm, an indispensable cation channel for the fertilization process, could be regulated by various steroid-like compounds in plants. Interestingly, these nonphysiological ligands would also disturb the activation of the cation channel of sperm induced by progesterone. Therefore, this study aimed to explore whether the compounds in R. volubilis affect the physiological regulation of the cation channel of sperm. The bioguided isolation of the whole herb of R. volubilis has resulted in the novel discovery of five new prenylated isoflavonoids, rhynchones A - E (1:  - 5: ), a new natural product, 5'-O-methylphaseolinisoflavan (6: ) (1H and 13C NMR data, Supporting Information), together with twelve known compounds (7:  - 18: ). Their structures were established by extensive spectroscopic analyses and drawing a comparison with literature data, while their absolute configurations were determined by electronic circular dichroism calculations. The experiments of intracellular Ca2+ signals and patch clamping recordings showed that rhynchone A (1: ) significantly reduced cation channel of sperm activation by competing with progesterone. In conclusion, our findings indicat that rhynchone A might act as a contraceptive compound by impairing the activation of the cation channel of sperm and thus prevent fertilization.

A unified operating procedure is crucial to evaluate sludge dewaterability, taking the setup of refrigerated storage time as an example.

Although extensive efforts have been carried out to study sludge dewatering mechanism, the lack of universal operating procedures makes it never be satisfactorily explained. This study evaluated the impact of a unified operating procedure on waste activated sludge (WAS) dewaterability by taking the setup of refrigerated storage time as an example. It was found that storage time played an important role in determining WAS dewaterability and sampled WAS should be refrigerated within 2 days. The results showed that after 2-d storage, sludge filterability was deteriorated significantly while the extent of dewatering efficiency had little change. Meanwhile, increasing storage time greatly increased the release of extracellular polymeric substances (EPS) and heavy metals, decreased sludge viscosity and weakened its network strength, but had little impact on the floc size and zeta potential of the sludge samples. It can hardly reveal the mechanism of storage time on sludge dewaterability due to the non-uniformity of operating procedures in literatures, which is normally ignored. This study emphasizes a unified operating procedure is crucial to evaluate WAS dewaterability. Therefore, more efforts shall be focused on establishing the uniform operating procedure while advancing applied research in the field of sludge dewatering.

Roles of apoptotic chondrocyte-derived CXCL12 in the enhanced chondroclast recruitment following methotrexate and/or dexamethasone treatment.

Intensive use of methotrexate (MTX) and/or dexamethasone (DEX) for treating childhood malignancies is known to cause chondrocyte apoptosis and growth plate dysfunction leading to bone growth impairments. However, mechanisms remain vague and it is unclear whether MTX and DEX combination treatment could have additive effects in the growth plate defects. In this study, significant cell apoptosis was induced in mature ATDC5 chondrocytes after treatment for 48 h with 10-5 M MTX and/or 10-6 M DEX treatment. PCR array assays with treated cells plus messenger RNA and protein expression confirmation analyses identified chemokine CXCL12 having the most prominent induction in each treatment group. Conditioned medium from treated chondrocytes stimulated migration of RAW264.7 osteoclast precursor cells and formation of osteoclasts, and these stimulating effects were inhibited by the neutralizing antibody for CXCL12. Additionally, while MTX and DEX combination treatment showed some additive effects on apoptosis induction, it did not have additive or counteractive effects on CXCL12 expression and its functions in enhancing osteoclastic recruitment and formation. In young rats treated acutely with MTX, there was increased expression of CXCL12 in the tibial growth plate, and more resorbing chondroclasts were found present at the border between the hypertrophic growth plate and metaphysis bone. Thus, the present study showed an association between induced chondrocyte apoptosis and stimulated osteoclastic migration and formation following MTX and/or DEX treatment, which could be potentially or at least partially linked molecularly by CXCL12 induction. This finding may contribute to an enhanced mechanistic understanding of bone growth impairments following MTX and/or DEX therapy.

Apple SUMO E3 ligase MdSIZ1 facilitates SUMOylation of MdARF8 to regulate lateral root formation.

Post-translational modification of proteins mediated by SIZ1, a small ubiquitin-like modifier (SUMO) E3 ligase, regulates multiple biological processes in plants. However, its role in the regulation of lateral root formation remains unclear. Here, we demonstrate that the apple SUMO E3 ligase MdSIZ1 promotes lateral root formation. Using a yeast-two-hybrid (Y2H) system, the auxin response factor MdARF8 was screened out as a protein-protein interaction partner of the SUMO-conjugating E2 enzyme MdSCE1, indicating that MdARF8 may be a substrate for MdSIZ1. The interaction between MdARF8 and MdSCE1 was confirmed by pull-down, Y2H and Co-immunoprecipitation assays. MdSIZ1 enhanced the conjugating enzyme activity of MdSCE1 to form a MdSCE1-MdSIZ1-MdARF8 complex, thereby facilitating SUMO modification. We identified two arginine substitution mutations at K342 and K380 in MdARF8 that blocked MdSIZ1-mediated SUMOylation, indicating that K342 and K380 are the principal SUMOylation sites of the MdARF8 protein. Moreover, MdARF8 promoted lateral root formation in transgenic apple plants, and the phenotype of reduced lateral roots in the Arabidopsis siz1-2 mutant was restored in siz1-2/MdARF8 complementary plants. Our findings reveal an important role for sumoylation in the regulation of lateral root formation in plants.

Enhanced photosynthetic nitrogen use efficiency and increased nitrogen allocation to photosynthetic machinery under cotton domestication.

Domestication involves dramatic phenotypic and physiological diversifications due to successive selection by breeders toward high yield and quality. Although photosynthetic nitrogen use efficiency (PNUE) is a major trait for understanding leaf nitrogen economy, it is unclear whether PNUE of cotton has been improved under domestication. Here, we investigated the effect of domestication on nitrogen allocation to photosynthetic machinery and PNUE in 25 wild and 37 domesticated cotton genotypes. The results showed that domesticated genotypes had higher nitrogen content per mass (Nm), net photosynthesis under saturated light (Asat), and PNUE but similar nitrogen content per area (Na) compared with wild genotypes. As expected, in both genotypes, PNUE was positively related to Asat but negatively correlated with Na. However, the relative contribution of Asat to PNUE was greater than the contribution from Na. Domesticated genotypes had higher nitrogen allocation to light-harvesting (NL, nitrogen in light-harvesting chlorophyll-protein complex), to bioenergetics (Nb, total nitrogen of cytochrome f, ferredoxin NADP reductase, and the coupling factor), and to Rubisco (Nr) than wild genotypes; however, the two genotype groups did not differ in PNUEp, the ratio of Asat to Np (itself the sum of NL, Nb, and Nr). Our results suggest that more nitrogen allocation to photosynthetic machinery has boosted Asat under cotton domestication. Improving the efficiency of nitrogen use in photosynthetic machinery might be future aim to enhance Asat of cotton.

Roles of MicroRNAs in Osteogenesis or Adipogenesis Differentiation of Bone Marrow Stromal Progenitor Cells.

Bone marrow stromal cells (BMSCs) are multipotent cells which can differentiate into chondrocytes, osteoblasts, and fat cells. Under pathological stress, reduced bone formation in favour of fat formation in the bone marrow has been observed through a switch in the differentiation of BMSCs. The bone/fat switch causes bone growth defects and disordered bone metabolism in bone marrow, for which the mechanisms remain unclear, and treatments are lacking. Studies suggest that small non-coding RNAs (microRNAs) could participate in regulating BMSC differentiation by disrupting the post-transcription of target genes, leading to bone/fat formation changes. This review presents an emerging concept of microRNA regulation in the bone/fat formation switch in bone marrow, the evidence for which is assembled mainly from in vivo and in vitro human or animal models. Characterization of changes to microRNAs reveals novel networks that mediate signalling and factors in regulating bone/fat switch and homeostasis. Recent advances in our understanding of microRNAs in their control in BMSC differentiation have provided valuable insights into underlying mechanisms and may have significant potential in development of new therapeutics.

miR-542-3p Attenuates Bone Loss and Marrow Adiposity Following Methotrexate Treatment by Targeting sFRP-1 and Smurf2.

Intensive methotrexate (MTX) treatment for childhood malignancies decreases osteogenesis but increases adipogenesis from the bone marrow stromal cells (BMSCs), resulting in bone loss and bone marrow adiposity. However, the underlying mechanisms are unclear. While microRNAs (miRNAs) have emerged as bone homeostasis regulators and miR-542-3p was recently shown to regulate osteogenesis in a bone loss context, the role of miR-542-3p in regulating osteogenesis and adipogenesis balance is not clear. Herein, in a rat MTX treatment-induced bone loss model, miR-542-3p was found significantly downregulated during the period of bone loss and marrow adiposity. Following target prediction, network construction, and functional annotation/ enrichment analyses, luciferase assays confirmed sFRP-1 and Smurf2 as the direct targets of miR-542-3p. miRNA-542-3p overexpression suppressed sFRP-1 and Smurf2 expression post-transcriptionally. Using in vitro models, miR-542-3p treatment stimulated osteogenesis but attenuated adipogenesis following MTX treatment. Subsequent signalling analyses revealed that miR-542-3p influences Wnt/ß-catenin and TGF-ß signalling pathways in osteoblastic cells. Our findings suggest that MTX treatment-induced bone loss and marrow adiposity could be molecularly linked to miR-542-3p pathways. Our results also indicate that miR-542-3p might be a therapeutic target for preserving bone and attenuating marrow fat formation during/after MTX chemotherapy.

A unique B cell epitope-based particulate vaccine shows effective suppression of hepatitis B surface antigen in mice.

OBJECTIVE: This study aimed to develop a novel therapeutic vaccine based on a unique B cell epitope and investigate its therapeutic potential against chronic hepatitis B (CHB) in animal models. METHODS: A series of peptides and carrier proteins were evaluated in HBV-tolerant mice to obtain an optimised therapeutic molecule. The immunogenicity, therapeutic efficacy and mechanism of the candidate were investigated systematically. RESULTS: Among the HBsAg-aa119-125-containing peptides evaluated in this study, HBsAg-aa113-135 (SEQ13) exhibited the most striking therapeutic effects. A novel immunoenhanced virus-like particle carrier (CR-T3) derived from the roundleaf bat HBV core antigen (RBHBcAg) was created and used to display SEQ13, forming candidate molecule CR-T3-SEQ13. Multiple copies of SEQ13 displayed on the surface of this particulate antigen promote the induction of a potent anti-HBs antibody response in mice, rabbits and cynomolgus monkeys. Sera and purified polyclonal IgG from the immunised animals neutralised HBV infection in vitro and mediated efficient HBV/hepatitis B virus surface antigen (HBsAg) clearance in the mice. CR-T3-SEQ13-based vaccination induced long-term suppression of HBsAg and HBV DNA in HBV transgenic mice and eradicated the virus completely in hydrodynamic-based HBV carrier mice. The suppressive effects on HBsAg were strongly correlated with the anti-HBs level after vaccination, suggesting that the main mechanism of CR-T3-SEQ13 vaccination therapy was the induction of a SEQ13-specific antibody response that mediated HBV/HBsAg clearance. CONCLUSIONS: The novel particulate protein CR-T3-SEQ13 suppressed HBsAg effectively through induction of a humoural immune response in HBV-tolerant mice. This B cell epitope-based therapeutic vaccine may provide a novel immunotherapeutic agent against chronic HBV infection in humans.

Serology characteristics of SARS-CoV-2 infection after exposure and post-symptom onset.

BACKGROUND: Timely diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a prerequisite for treatment and prevention. The serology characteristics and complement diagnosis value of the antibody test to RNA test need to be demonstrated. METHOD: Serial sera of 80 patients with PCR-confirmed coronavirus disease 2019 (COVID-19) were collected at the First Affiliated Hospital of Zhejiang University, Hangzhou, China. Total antibody (Ab), IgM and IgG antibodies against SARS-CoV-2 were detected, and the antibody dynamics during the infection were described. RESULTS: The seroconversion rates for Ab, IgM and IgG were 98.8%, 93.8% and 93.8%, respectively. The first detectible serology marker was Ab, followed by IgM and IgG, with a median seroconversion time of 15, 18 and 20 days post exposure (d.p.e.) or 9, 10 and 12 days post onset (d.p.o.), respectively. The antibody levels increased rapidly beginning at 6 d.p.o. and were accompanied by a decline in viral load. For patients in the early stage of illness (0-7 d.p.o), Ab showed the highest sensitivity (64.1%) compared with IgM and IgG (33.3% for both; p<0.001). The sensitivities of Ab, IgM and IgG increased to 100%, 96.7% and 93.3%, respectively, 2 weeks later. When the same antibody type was detected, no significant difference was observed between enzyme-linked immunosorbent assays and other forms of immunoassays. CONCLUSIONS: A typical acute antibody response is induced during SARS-CoV-2 infection. Serology testing provides an important complement to RNA testing in the later stages of illness for pathogenic-specific diagnosis and helpful information to evaluate the adapted immunity status of patients.

Coptisine suppresses proliferation and inhibits metastasis in human pancreatic cancer PANC-1 cells.

The effects of coptisine against advanced stage of human pancreatic carcinoma PANC-1 cells was investigated in vitro. Coptisine (25-150 µM) treatment for 48 h caused dose-dependent cell growth inhibition by using CCK-8 assay. Additionally, coptisine was found to inhibit PANC-1 cells metastasis by the wound healing assay. Flow cytometry data indicated that coptisine (25-100 µM) exhibited dose-dependent G1 phase arrest and moderate reduction of S phase. Coptisine was also found to inhibit ERK phosphorylation and total ERK levels. Our research suggested that coptisine would be a potential therapeutic drug for the treatment of pancreatic cancer.

The R2R3 MYB transcription factor MdMYB30 modulates plant resistance against pathogens by regulating cuticular wax biosynthesis.

BACKGROUND: The MYB transcription factor family is one of the largest transcriptional factor families in plants and plays a multifaceted role in plant growth and development. However, MYB transcription factors involved in pathogen resistance in apple remain poorly understood. RESULTS: We identified a new MYB family member from apple, and named it MdMYB30. MdMYB30 was localized to the nucleus, and was highly expressed in young apple leaves. Transcription of MdMYB30 was induced by abiotic stressors, such as polyethylene glycol and abscisic acid. Scanning electron microscopy and gas chromatograph-mass spectrometry analyses demonstrated that ectopically expressing MdMYB30 in Arabidopsis changed the wax content, the number of wax crystals, and the transcription of wax-related genes. MdMYB30 bound to the MdKCS1 promoter to activate its expression and regulate wax biosynthesis. MdMYB30 also contributed to plant surface properties and increased resistance to the bacterial strain Pst DC3000. Furthermore, a virus-based transformation in apple fruits and transgenic apple calli demonstrated that MdMYB30 increased resistance to Botryosphaeria dothidea. Our findings suggest that MdMYB30 plays a vital role in the accumulation of cuticular wax and enhances disease resistance in apple. CONCLUSIONS: MdMYB30 bound to the MdKCS1 gene promoter to activate its transcription and regulate cuticular wax content and composition, which influenced the surface properties and expression of pathogenesis-related genes to resistance against pathogens. MdMYB30 appears to be a crucial element in the formation of the plant cuticle and confers apple with a tolerance to pathogens.

Apple AP2/EREBP transcription factor MdSHINE2 confers drought resistance by regulating wax biosynthesis.

MAIN CONCLUSION: This study showed that AP2/EREBP transcription factor MdSHINE2 functioned in mediating cuticular permeability, sensitivity to abscisic acid (ABA), and drought resistance by regulating wax biosynthesis. Plant cuticular wax plays crucial roles in protecting plants from environmental stresses, particularly drought stress. Many enzymes and transcription factors involved in wax biosynthesis have been identified in plant species. In this study, we identified an AP2/EREBP transcription factor, MdSHINE2 from apple, which is a homolog of AtSHINE2 in Arabidopsis. MdSHINE2 was constitutively expressed at different levels in various apple tissues, and the transcription level of MdSHINE2 was induced substantially by abiotic stress and hormone treatments. MdSHINE2-overexpressing Arabidopsis exhibited great change in cuticular wax crystal numbers and morphology and wax composition of leaves and stems. Moreover, MdSHINE2 heavily influenced cuticular permeability, sensitivity to abscisic acid, and drought resistance.