ABSTRACT
Purpose
To utilize a novel type of polymer-drug conjugate micelle to enhance the delivery of low-potency curcumin.
Methods
Multiple curcumin molecules were conjugated to poly(lactic acid) ...(PLA) via tris(hydroxymethyl)aminomethane (Tris) linker producing the hydrophobic drug-binding block; methoxy-poly(ethylene glycol) (mPEG) was employed as the hydrophilic block. Micelles were characterized by size, loading capacity, stability, and critical micelle concentration (CMC). Human hepatocellular carcinoma (HepG2) cells were employed to assess cytotoxicity and intracellular targeting ability of micelles.
Results
mPEG-PLA-Tris-Cur micelles were within nanorange (<100 nm). CMC of such micelles (2.3 ± 0.4 μg/mL) was 10 times lower than mPEG-PLA micelles (27.4 ± 0.8 μg/mL). Curcumin loading in mPEG-PLA-Tris-Cur micelles reached 18.5 ± 1.3% (w/w), compared to traditional mPEG-PLA micelles at 3.6 ± 0.4% (w/w). IC
50
of mPEG-PLA-Tris-Cur micelles (~22 μg/mL at curcumin-equivalent dose) was similar to unmodified curcumin. Placebo and drug-encapsulated conjugate micelles could be efficiently internalized to cytoplasmic compartment of HepG2 cells.
Conclusions
Micelle-forming polymer-drug conjugates containing multiple drug molecules were an efficient means to increase loading and intracellular delivery of low-potency curcumin.
As in other eukaryotes, protein kinases play major regulatory roles in filamentous fungi. Although the genomes of many plant pathogenic fungi have been sequenced, systematic characterization of their ...kinomes has not been reported. The wheat scab fungus Fusarium graminearum has 116 protein kinases (PK) genes. Although twenty of them appeared to be essential, we generated deletion mutants for the other 96 PK genes, including 12 orthologs of essential genes in yeast. All of the PK mutants were assayed for changes in 17 phenotypes, including growth, conidiation, pathogenesis, stress responses, and sexual reproduction. Overall, deletion of 64 PK genes resulted in at least one of the phenotypes examined, including three mutants blocked in conidiation and five mutants with increased tolerance to hyperosmotic stress. In total, 42 PK mutants were significantly reduced in virulence or non-pathogenic, including mutants deleted of key components of the cAMP signaling and three MAPK pathways. A number of these PK genes, including Fg03146 and Fg04770 that are unique to filamentous fungi, are dispensable for hyphal growth and likely encode novel fungal virulence factors. Ascospores play a critical role in the initiation of wheat scab. Twenty-six PK mutants were blocked in perithecia formation or aborted in ascosporogenesis. Additional 19 mutants were defective in ascospore release or morphology. Interestingly, F. graminearum contains two aurora kinase genes with distinct functions, which has not been reported in fungi. In addition, we used the interlog approach to predict the PK-PK and PK-protein interaction networks of F. graminearum. Several predicted interactions were verified with yeast two-hybrid or co-immunoprecipitation assays. To our knowledge, this is the first functional characterization of the kinome in plant pathogenic fungi. Protein kinase genes important for various aspects of growth, developmental, and infection processes in F. graminearum were identified in this study.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The WRKY proteins constitute a large family of transcription factors that have been known to play a wide range of regulatory roles in multiple biological processes. Over the past few years, many ...reports have focused on analysis of evolution and biological function of WRKY genes at the whole genome level in different plant species. However, little information is known about WRKY genes in melon (Cucumis melo L.). In the present study, a total of 56 putative WRKY genes were identified in melon, which were randomly distributed on their respective chromosomes. A multiple sequence alignment and phylogenetic analysis using melon, cucumber and watermelon predicted WRKY domains indicated that melon WRKY proteins could be classified into three main groups (I-III). Our analysis indicated that no recent duplication events of WRKY genes were detected in melon, and strong purifying selection was observed among the 85 orthologous pairs of Cucurbitaceae species. Expression profiles of CmWRKY derived from RNA-seq data and quantitative RT-PCR (qRT-PCR) analyses showed distinct expression patterns in various tissues, and the expression of 16 CmWRKY were altered following powdery mildew infection in melon. Besides, we also found that a total of 24 WRKY genes were co-expressed with 11 VQ family genes in melon. Our comparative genomic analysis provides a foundation for future functional dissection and understanding the evolution of WRKY genes in cucurbitaceae species, and will promote powdery mildew resistance study in melon.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To determine that differential bone remodeling mechanism (especially Wnt signaling) in hindlimb unloaded rats and hibernating Daurian ground squirrels, the bone microstructure, mechanical properties, ...and expression levels of bone remodeling related proteins and key proteins of Wnt/β-catenin signaling were analyzed in this study. The thickness of cortical and trabecular bone was decreased in femur of hindlimb unloaded rats, while it was maintained in femur of hibernating ground squirrels. Interestingly, the ultimate bending energy and ultimate normalized displacement were reduced and the bending rigidity was increased in tibia of hibernating ground squirrels. Besides, the protein level of Runx2 was decreased in femur and tibia of unloaded rats, while it was maintained in tibia and even increased in femur of hibernating ground squirrels. The protein levels of RANKL and MMP-9 were increased in femur and tibia in unloaded rats, while they were maintained in both femur and tibia of hibernating ground squirrels. The protein level of GSK-3β was increased in femur and tibia of unloaded rats, while it was maintained in both femur and tibia of hibernating ground squirrels. The phospho-β-catenin expression was increased in both femur and tibia of unloaded rats, while it was only decreased in femur, but maintained in tibia of hibernating ground squirrels. In conclusion, the femur and tibia in hindlimb unloaded rats showed obvious bone loss, while they mitigated disuse-induced bone loss in hibernating ground squirrels, involving differential protein expression of key molecules in bone remodeling. In comparison with hindlimb unloaded rats, promoting osteoblast differentiation through activating canonical GSK-3β/β-catenin signaling involving Runx2 might be an adaptation to natural disuse in femur of hibernating Daurian ground squirrels. However, there was no statistical change in the protein levels of bone formation related proteins, GSK-3β and phospho-β-catenin in tibia of hibernating Daurian ground squirrels.
This study compared the effects on bone metabolism and morphology of pathological obesity induced by excessive fat intake in a non-hibernator (mice) versus healthy obesity due to pre-hibernation ...fattening in a hibernator (ground squirrels). Kunming mice were fed a high-fat diet to provide a model of pathological obesity (OB group). Daurian ground squirrels fattened naturally in their pre-hibernation season (PRE group) were used as a healthy obesity model. Micro-computed tomography (micro-CT) and three-point bending tests were used to determine the microstructure and mechanical properties of bone. Western blots were used to analyze protein expression levels related to bone metabolism (Runt-related transcription factor 2 (RunX2), osteocalcin (OCN), alkaline phosphatase (ALP), osteoprotegerin (OPG), receptor activator of nuclear factor-κB ligand (RANKL), cathepsin K, matrix metallopeptidase 9 (MMP9), patched protein homolog 1 (Ptch1), phosphorylated β-catenin (P-β-catenin), and glycogen synthase kinase-3β (GSK-3β)). Compared with controls, there was no obvious bone loss in the OB mice, and the stiffness of the femur was increased significantly. Compared with summer active squirrels, bone formation was enhanced but the mechanical properties did not change in the PRE group squirrels. In OB mice, western blots showed significantly increased expression levels of all proteins except RunX2, OPG, and Ptch1. PRE ground squirrels showed significantly increased expression of most proteins except OCN and Ptch1, which decreased significantly, and P-β-catenin and OPG, which did not change. In conclusion, for non-hibernating mice, moderate obesity had a certain protective effect on bones, demonstrating two-way regulation, increasing both bone loss and bone formation. For pre-hibernating ground squirrels, the healthy obesity acquired before hibernation had a positive effect on the microstructure of bones, and also enhanced the expression levels of proteins related to bone formation, bone resorption, and Wnt signaling.
Background: Both pathological conditions and hibernation can affect the barrier function of small intestine mucosa. However, the effect of hibernation on the barrier function of colonic mucosa ...remains unclear. Methods: We investigated morphological changes in colonic mucosa, the concentrations of specific proteins and molecules, and the enzymatic activity of diamine oxidase (DAO), in serum and colonic tissue; the expression of tight junction proteins and mucin, and the changes in inflammatory, farnesoid X receptor (FXR)–small heterodimer partner (SHP), and apoptosis-related molecules that could play a role in gut permeability changes in Daurian ground squirrels in summer active (SA), late torpor (LT), and interbout arousal (IBA) periods. Results: The results show that hibernation reduced the thickness of the colonic mucosa and the depth of the crypt, decreased the number of goblet cells (GCs), and damaged the structure of some microvilli. The concentrations of proteins and molecules, and the enzymatic activity of DAO, were all increased in the serum and colon, and the localization of tight junction proteins and mucin in the colonic mucosa were altered (compensatory response). Although the ground squirrels ate during the interbout arousal period, the changes remained similar to the response to torpor. Inflammation, apoptosis–anti-apoptosis, and FXR–SHP signaling may be involved in the possible changes in intestinal gut permeability during the torpor–arousal cycle in Daurian ground squirrels. In addition, periodic interbout arousal may play an inflammation-correcting role during the long hibernation season of Daurian ground squirrels.
We focused on pathological obesity induced by excessive fat intake (nutritional obesity) in non-hibernator and healthy obesity due to pre-hibernation (PRE) fat storage in hibernator to study the ...effects of different types of obesity on skeletal muscle protein metabolism and cell regeneration. Kunming mice were fed with high-fat diet for 3 months to construct a pathological obesity model. Daurian ground squirrels fattened naturally before hibernation were used as a healthy obesity model. Body weight, adipose tissue wet weight, gastrocnemius muscle wet weight, muscle fiber cross-sectional area (CSA) and fiber type distribution were measured. The protein expression levels related to protein degradation (MuRF-1, atrogin-1, calpain1, calpain2, calpastatin, desmin, troponin T, Beclin-1, LC3-II), protein synthesis (P-Akt, P-mTORC1, P-S6K1, P-4E-BP1) and cell regeneration (MyoD, myogenin, myostatin) were detected by Western blot. As a result, the body weight and adipose tissue wet weight were both significantly increased in high fat obese (OB) mice and pre-hibernation fat (PRE) ground squirrels. The muscle wet weight, ratio of muscle wet weight to body weight, and muscle fiber CSA were significantly decreased, while the percentage of MHC I fiber isoform was significantly increased in gastrocnemius muscle of OB mice compared with the control (CON) group. The protein expression levels of P-Akt, P-mTORC1, P-4E-BP1 and myogenin were significantly decreased, while those of calpain1, calpain2, MuRF-1 and myostatin were significantly increased in the OB mice. In the ground squirrels, the muscle wet weight, muscle fiber CSA and percentage of MHC I fiber isoform all showed no change in the gastrocnemius muscle in the PRE group compared with the summer active (SA) group. The protein expression levels of P-Akt, P-mTORC1, P-S6K1 and MyoD were significantly increased, while those of Beclin-1 and LC3-II were significantly decreased in the PRE ground squirrels. This study demonstrated that the decrease in protein expression levels in the Akt/ mTOR pathway (P-Akt, P-mTORC1 and P-4E-BP1) and cell regeneration (myogenin) and the increase in protein expression levels of the calpain pathway (calpain1 and calpain2) and ubiquitin-proteasome pathway (MuRF-1) were involved in the mechanism of muscle atrophy in gastrocnemius muscle of the pathologically obese Kunming mice induced by high-fat diet. In contrast, the increased protein expression levels of the Akt/mTOR pathway (P-Akt, P-mTORC1 and P-S6K1) and cell regeneration (MyoD), and the decreased protein expression levels of the autophagy lysosomal pathway (Beclin-1 and LC3-II) were involved in the mechanism of anti-atrophy in gastrocnemius muscle of the healthy obese ground squirrels fattened before hibernation.
A recombinant strain (BS168-ΔbdhA) that increased co-production of MK-7 and NK was constructed by knocking out the 2,3-butanediol dehydrogenase gene (bdhA) of Bacillus subtilis 168 to reduce the ...carbon spillover. The results showed that the 2,3- butanediol content in the recombinant strain was reduced by 64% to 2.76 g/L. The recombinant strain had an MK-7 production of 30.6 mg/L and an NK activity of 6.5 FU/mL. RNA-Seq analysis showed that: bdhA knockdown blocked the carbon flux of 2,3-butanediol and promoted glycerol uptake, and the carbon flux flowed more to the MK-7 and NK synthesis pathways. The negative regulator of NK, codY, was down-regulated by 2.19-fold. secA, which is responsible for the energy supply of transmembrane proteins, was down-regulated by 0.37-fold, the Tat secretion pathway was up-regulated by 2.8-fold and 0.5-fold for tatAD and tatC, respectively. This study revealed the mechanism of co-production of MK-7 and NK in recombinant strains for the first time and revealed potential molecular targets to promote the co-production of MK-7 and NK, which will provide a new strategy for metabolic engineering to increase the production of MK-7 and NK.
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•First use of metabolically engineered commons nattokinase and NK.•bdhA knockdown promotes redistribution of carbon flow towards MK-7 and NK synthesis.•bdhA knockdown promotes extracellular secretion of MK-7 and NK.
Ginger (
Rosc.) is a herbal plant, widely grown in China for its medicinal and culinary purposes. In July 2020, a new rhizome rot disease was observed on ginger in Laiwu, Shandong Province, China. ...The disease symptoms were observed on both above-ground and underground plant parts. The above ground stems and leaves becoming withered and yellow, and water-soaked symptoms were observed on the collar region. The diseased rhizomes were poorly developed with brown lesion and eventually they would rot, without offensive odors. Disease incidence was estimated at approximately 5% across the survey area. To isolate the pathogen, tissues from 30 rhizomes were cut from the border between diseased and healthy tissue, surface sterilized in 75% alcohol for 15 s, soaked in 0.1% mercuric chloride for 1 min, washed with sterile distilled water three times, and plated on potato dextrose agar (PDA) at 25°C for 2-3 days. Twenty nine fungal isolates with similar morphological characteristics were obtained and pure cultures were obtained using single spore isolation. The colony of AQJ-1, a representative isolate, on PDA was cottony, fluffy, white, and beige coloration on the reverse side at first, and subsequently many black sporangia were produced. The sporangia were black, sub-globose, and 45.2-181.7 μm (n = 50) in diameter. The sporangiospores were unequal, globose or sub-globose, about 3.2-8.7 × 4.6-12.3μm (n = 50) in diameter. For the molecular characterization, genomic DNA was extracted by modified CTAB method (Niu et al., 2008). Internal transcribed spacer (ITS) region and translation elongation factor 1-alpha (EF-1α) gene were amplified using the primer pairs ITS1/ITS4 (White et al., 1990) and MEF10/MEF4 (Abe et al., 2007), respectively. The ITS and EF-1α sequences of isolate AQJ-1 were submitted to GenBank (MN606288 and MN735220, respectively). The BLASTn analysis of the sequences showed 99%-100% similarity to the sequences of
strain CBS 120.12 (MH854609, AB281529, respectively). Therefore, based on morphological and molecular characteristics, isolate AQJ-1 was identified as R. oryzae. For pathogenicity tests, thirty ginger seedlings (Laiwu Big Ginger) were grown for 30 days in plastic pots and removed from the pots and the rhizomes washed in running tap water. The rhizomes of fifteen ginger seedlings were attached to a 7 mm agar disk from a plate containing 2-day-old mycelium, and the other fifteen seedlings were attached to agar disk without mycelium as control. Then the inoculated and control seedlings were planted in pots and were kept in separate chambers in a greenhouse at 25±2 °C. After 14 days, the same symptoms of rhizome rot were observed in all inoculated plants as previously described, and no symptoms were observed on the control plants. The pathogen was re-isolated from symptomatic tissues, and was identified as R. oryzae, which full-filled the Koch's postulates. To our knowledge, this is the first report of
causing rhizome rot on ginger in China. This disease may pose a potential threat to ginger production in China.
Summary
The versatile functions of SR (serine/arginine‐rich) proteins in pre‐mRNA splicing and processing are modulated by reversible phosphorylation. Previous studies showed that FgPrp4, the only ...protein kinase among spliceosome components, is important for intron splicing and the FgSrp1 SR protein is phosphorylated at five conserved sites in Fusarium graminearum. In this study, we showed that the Fgsrp1 deletion mutant rarely produced conidia and caused only limited symptoms on wheat heads and corn silks. Deletion of FgSRP1 also reduced ascospore ejection and deoxynivalenol (DON) production. Interestingly, FgSRP1 had two transcript isoforms due to alternative splicing and both of them were required for its normal functions in growth and DON biosynthesis. FgSrp1 localized to the nucleus and interacted with FgPrp4 in vivo. Deletion of all four conserved phosphorylation sites but not individual ones affected the FgSRP1 function, suggesting their overlapping functions. RNA‐seq analysis showed that the expression of over thousands of genes and splicing efficiency in over 140 introns were affected. Taken together, FgSRP1 is important for conidiation, and pathogenesis and alternative splicing is important for its normal functions. The FgSrp1 SR protein is likely important for pre‐mRNA processing or splicing of various genes in different developmental and infection processes.
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