New insights into the rapid germination process of lentil and cowpea seeds: High thiamine and folate, and low α-galactoside content

During germination sensu-stricto in pulses, an increase in the content of thiamine (B1) and folate (B9) vitamins is expected, along with a reduction in α-galactoside levels. The aim of our study was to optimize germination to increase the nutritional quality of lentils and cowpeas. An experimental design was carried out at 12 h and 24 h of imbibition to analyze the effects of temperature, light, and water content on thiamine, folate, and α-galactoside content. Germination increased thiamine content by 152% in lentils, while in cowpeas, the increase was only 10%. Folate content in cowpea increased by 33%, while α-galactoside content decreased by 99% in cowpeas and by 48% in lentils. Germination sensu-stricto can be safely implemented by any food company worldwide as it is simple and involves less sanitary risk than sprouting. This opens up opportunities for enhancing food nutrient content and new ways of processing pulses.

Enhancement of pyranoanthocyanin formation in blueberry wine with non-Saccharomyces yeasts

The development of blueberry wine provides an alternative method for maintaining the nutritional value and extending the shelf life of blueberries. However, anthocyanin loss and off-flavor compound generation during fermentation impair blueberry wine color and quality. Hydroxycinnamate decarboxylase from yeast can catalyze the conversion of hydroxycinnamic acids to vinylphenols, which later may condense with anthocyanins to form more stable vinylphenolic pyranoanthocyanins. In this study, 10 non-Saccharomyces yeasts from Daqu that showed hydroxycinnamate decarboxylase activity were screened. Among the 10 strains, Wickerhamomyces anomalus Y5 showed the highest consumption (34.59%) of the total tested phenolic acids and almost no H2S production. Furthermore, Y5 seemed to produce four vinylphenol pyranoanthocyanins (cyanidin-3-O-galactoside/glucoside-4-vinylcatechol, cyanidin-3-O-galactoside/glucoside-4-vinylsyringol, malvidin-4-vinylguaiacol, and malvidin-4-vinylcatechol) during blueberry wine fermentation, which may improve the color stability of blueberry wine. These findings provide new insights for improving the quality of blueberry wine using non-Saccharomyces yeasts.

A Biomimetic Synthetic Strategy Can Provide Keratan Sulfate I and II Oligosaccharides with Diverse Fucosylation and Sulfation Patterns

Keratan sulfate (KS) is a proteoglycan that is widely expressed in the extracellular matrix of various tissue types, where it performs multiple biological functions. KS is the least understood proteoglycan, which in part is due to a lack of panels of well-defined KS oligosaccharides that are needed for structure-binding studies, as analytical standards, to examine substrate specificities of keratinases, and for drug development. Here, we report a biomimetic approach that makes it possible to install, in a regioselective manner, sulfates and fucosides on oligo-N-acetyllactosamine (LacNAc) chains to provide any structural element of KS by using specific enzyme modules. It is based on the observation that α1,3-fucosides, α2,6-sialosides and C-6 sulfation of galactose (Gal6S) are mutually exclusive and cannot occur on the same LacNAc moiety. As a result, the pattern of sulfation on galactosides can be controlled by installing α1,3-fucosides or α2,6-sialosides to temporarily block certain LacNAc moieties from sulfation by keratan sulfate galactose 6-sulfotransferase (CHST1). The patterns of α1,3-fucosylation and α2,6-sialylation can be controlled by exploiting the mutual exclusivity of these modifications, which in turn controls the sites of sulfation by CHST1. Late-stage treatment with a fucosidase or sialidase to remove blocking fucosides or sialosides provides selectively sulfated KS oligosaccharides. These treatments also unmasked specific galactosides for further modification by CHST1. To showcase the potential of the enzymatic strategy, we have prepared a range of poly-LacNAc derivatives having different patterns of fucosylation and sulfation and several N-glycans decorated by specific arrangements of sulfates.

CCCTC-binding factor: the specific transcription factor of β-galactoside α-2,6-sialyltransferase 1 that upregulates the sialylation of anti-citrullinated protein antibodies in rheumatoid arthritis

OBJECTIVE

Sialylation of the crystallizable fragment (Fc) of ACPAs, which is catalysed by β-galactoside α-2,6-sialyltransferase 1 (ST6GAL1) could attenuate inflammation of RA. In this study, we screened the transcription factor of ST6GAL1 and elucidated the mechanism of transcriptionally upregulating sialylation of ACPAs in B cells to explore its role in the progression of RA.

METHODS

Transcription factors interacting with the P2 promoter of ST6GAL1 were screened by DNA pull-down and liquid chromatography with tandem mass spectrometry (LC-MS/MS), and verified by chromatin immunoprecipitation (ChIP), dual luciferase reporter assay and electrophoretic mobility shift assay (EMSA). The function of the CCCTC-binding factor (CTCF) on the expression of ST6GAL1 and the inflammatory effect of ACPAs were verified by knocking down and overexpressing CTCF in B cells. The CIA model was constructed from B cell-specific CTCF knockout mice to explore the effect of CTCF on arthritis progression.

RESULTS

We observed that the levels of ST6GAL1 and ACPAs sialylation decreased in the serum of RA patients and were negatively correlated with DAS28 scores. Subsequently, CTCF was screened and verified as the transcription factor interacting with the P2 promoter of ST6GAL1, which enhances the sialylation of ACPAs, thus weakening the inflammatory activity of ACPAs. Furthermore, the above results were also verified in the CIA model constructed from B cell-specific CTCF knockout mice.

CONCLUSION

CCCTC-binding factor is the specific transcription factor of β-galactoside α-2,6-sialyltransferase 1 in B cells that upregulates the sialylation of ACPAs in RA and attenuates the disease progression.

Identification of antiviral phytochemicals from cranberry as potential inhibitors of SARS-CoV-2 main protease (Mpro)

Cranberry phytochemicals are known to possess antiviral activities. In the current study, we explored the therapeutic potential of cranberry against SARS-CoV-2 by targeting its main protease (Mpro) enzyme. Firstly, phytochemicals of cranberry origin were identified from three independent databases. Subsequently, virtual screening, using molecular docking and molecular dynamics simulation approaches, led to the identification of three lead phytochemicals namely, cyanidin 3-O-galactoside, β-carotene and epicatechin. Furthermore, in vitro enzymatic assays revealed that cyanidin 3-O-galactoside had the highest inhibitory potential with IC50 of 9.98 μM compared to the other two phytochemicals. Cyanidin 3-O-galactoside belongs to the class of anthocyanins. Anthocyanins extracted from frozen cranberry also exhibited the highest inhibitory potential with IC50 of 23.58 μg/ml compared to the extracts of carotenoids and flavanols, the class for β-carotene and epicatechin, respectively. Finally, we confirm the presence of the phytochemicals in the cranberry extracts using targeted LC-MS/MS analysis. Our results, therefore, indicate that the identified cranberry-derived bioactive compounds as well as cranberry could be used for therapeutic interventions against SARS-CoV-2.

Sex-dependent expression of galectin-1, a cardioprotective β-galactoside-binding lectin, in human calcific aortic stenosis

We aimed to analyze sex-related differences in galectin-1 (Gal-1), a β-galactoside-binding lectin, in aortic stenosis (AS) and its association with the inflammatory and fibrocalcific progression of AS. Gal-1 was determined in serum and aortic valves (AVs) from control and AS donors by western blot and immunohistochemistry. Differences were validated by ELISA and qPCR in AS samples. In vitro experiments were conducted in primary cultured valve interstitial cells (VICs). Serum Gal-1 was not different neither between control and AS nor between men and women. There was no association between circulating and valvular Gal-1 levels. The expression of Gal-1 in stenotic AVs was higher in men than women, even after adjusting for confounding factors, and was associated with inflammation, oxidative stress, extracellular matrix remodeling, fibrosis, and osteogenesis. Gal-1 (LGALS1) mRNA was enhanced within fibrocalcific areas of stenotic AVs, especially in men. Secretion of Gal-1 was up-regulated over a time course of 2, 4, and 8 days in men's calcifying VICs, only peaking at day 4 in women's VICs. In vitro, Gal-1 was associated with similar mechanisms to those in our clinical cohort. β-estradiol significantly up-regulated the activity of an LGALS1 promoter vector and the secretion of Gal-1, only in women's VICs. Supplementation with rGal-1 prevented the effects elicited by calcific challenge including the metabolic shift to glycolysis. In conclusion, Gal-1 is up-regulated in stenotic AVs and VICs from men in association with inflammation, oxidative stress, matrix remodeling, and osteogenesis. Estrogens can regulate Gal-1 expression with potential implications in post-menopause women. Exogenous rGal-1 can diminish calcific phenotypes in both women and men.

Chemo-Enzymatic Synthesis of Isomeric I-branched Polylactosamines Using Traceless Blocking Groups

Poly-N-acetyl lactosamines (polyLacNAc) are common structural motifs of N- and O-linked glycan, glycosphingolipids and human milk oligosaccharides. They can be branched by the addition of β1,6-linked N-acetyl-glucosamine (GlcNAc) moieties to internal galactoside (Gal) residues by the I-branching enzyme beta-1,6-N-acetylglucosaminyltransferase 2 (GCNT2). I-branching has been implicated in many biological processes and is also associated with various diseases such as cancer progression. Currently, there is a lack of methods that can install, in a regioselective manner, I-branches and allows the preparation of isomeric poly-LacNAc derivatives. Here, we described a chemo-enzymatic strategy that addresses this deficiency and is based on the enzymatic assembly of an oligo-LacNAc chain that at specific positions is modified by a GlcNTFA moiety. Replacement of the trifluoroacetyl (TFA) moiety by tert-butyloxycarbonyl (Boc) gives compounds in which the galactoside at the proximal site is blocked from modification by GCNT2. After elaboration of the antennae, the Boc group can be removed, and the resulting amine acetylated to give natural I-branched structures. It is also shown that fucosides can function as a traceless blocking group that can provide complementary I-branched structures from a single precursor. The methodology made it possible to synthesize a library of polyLacNAc chains having various topologies.

Integrated analysis of the metabolome and transcriptome provides insights into anthocyanin biosynthesis of cashew apple

The cashew apple remains an underutilized agricultural product despite its abundance as a by-product of cashew nut production. Anthocyanins are water-soluble pigments responsible for red, purple, and blue hues in plant tissues and have various health-promoting properties. To investigate the anthocyanin biosynthesis in cashew apples, fruits with varying peel colors from three cultivars were subjected to integrative analyses with metabolomics and transcriptomics. Through a UPLC-ESI-MS/MS-based targeted metabolomics analysis, a total of 26 distinct anthocyanin compounds were identified in the fruits of the three cashew cultivars. Subsequent quantification revealed that Pelargonidin-3-O-galactoside, Petunidin-3-O-arabinoside, and Cyanidin-3-O-galactoside were the primary contributors responsible for the red pigmentation in cashew apple peels. Following transcriptomic analysis showed that the expression levels of anthocyanin biosynthetic genes were predominantly higher in the red cashew apples as compared to the other two cultivars. Moreover, correlation analysis revealed that eight potential transcription factors implicated in the regulation of anthocyanin biosynthesis. Among these, four transcription factors exhibited positive correlations with both anthocyanin contents and anthocyanin biosynthetic gene expression, while the remaining four transcription factors displayed negative correlations. These findings provide a comprehensive understanding of the molecular basis of anthocyanin biosynthesis in cashew apple peels.

Dietary flavonoid myricetin 3-O-galactoside suppresses α-melanocyte stimulating hormone-induced melanogenesis in B16F10 melanoma cells by regulating PKA and ERK1/2 activation

Melanogenesis is the process where skin pigment melanin is produced through tyrosinase activity. Overproduction of melanin causes skin disorders such as freckles, spots, and hyperpigmentation. Myricetin 3-O-galactoside (M3G) is a dietary flavonoid with reported bioactivities. M3G was isolated from Limonium tetragonum and its anti-melanogenic properties were investigated in α-melanocyte stimulating hormone-stimulated B16F10 melanoma cells. The in vitro anti-melanogenic capacity of M3G was confirmed by inhibited tyrosinase and melanin production. M3G-mediated suppression of melanogenic proteins, tyrosinase, microphthalmia-associated transcription factor (MITF), and tyrosinase-related proteins (TRP)-1 and TRP-2, were confirmed by mRNA and protein levels, analyzed by RT-qPCR and Western blot, respectively. Furthermore, M3G suppressed Wnt signaling through the inhibition of PKA phosphorylation. M3G also suppressed the consequent phosphorylation of CREB and nuclear levels of MITF. Analysis of MAPK activation further revealed that M3G increased the activation of ERK1/2 while p38 and JNK activation remained unaffected. Results showed that M3G suppressed melanogenesis in B16F10 cells by decreasing tyrosinase production and therefore inhibiting melanin formation. A possible action mechanism was the suppression of CREB activation and upregulation of ERK phosphorylation which might cause the decreased nuclear levels of MITF. In conclusion, M3G was suggested to be a potential nutraceutical with anti-melanogenic properties.

Iridoid- and flavonoid-enriched fractions of Cornus sanguinea and Cornus mas exert antioxidant and anti-inflammatory effects and inhibit key enzymes in the treatment of metabolic disorders

Background: Berry fruits are recognized as a "superfood" due to their high content of bioactive compounds and health benefits. Scope and approach: Herein, extracts of Cornus sanguinea and Cornus mas fresh and dried fruits obtained by different extraction procedures (ethanolic and hydroalcoholic maceration, ultrasound-assisted extraction, and Soxhlet apparatus) were analysed using liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry (LC-ESI-QTOF-MS) and compared to identify the main healthy compounds and their impact on the inhibition of key enzymes (pancreatic lipase, α-glucosidase, and α-amylase) associated with metabolic disorders. The antioxidant activity and inhibition of nitric oxide (NO) and NF-κB pathway were also investigated. Key findings and conclusions: Flavonoids, iridoids, and phenolic acids were the main classes of identified compounds. Herein, kaempferol 3-O-galactoside, kaempferol 3-O-glucoside, quercetin, quercetin 3-O-xyloside, and myricetin 3-O-galactoside were detected for the first time in C. sanguinea. Remarkable antioxidant effects and promising α-glucosidase and lipase inhibitory activity were observed with extracts obtained by hydroalcoholic maceration of both Cornus dried fruits. Consequently, these extracts were subjected to fractionation using Amberlite XAD-16 resin. The most promising biological activities, which are attributed to the presence of some flavonoids and iridoids, were detected with the C. sanguinea fractions, in particular SD2(II). The results of this study offer new insights into the potential development of functional foods, nutraceuticals, and food supplements using the Cornus species.

Quercetin 3-O-Galactoside Isolated from Limonium tetragonum Inhibits Melanogenesis by Regulating PKA/MITF Signaling and ERK Activation

Quercetin 3-O-galactoside (Q3G) is a common dietary flavanol that has been shown to possess several bioactivities, including anti-melanogenesis. However, how Q3G exerts its anti-melanogenic effect has not been studied. The current study, therefore aimed to investigate the anti-melanogenesis potential of Q3G and elucidate the underlying action mechanism in α-melanocyte-stimulating hormone (α-MSH)-induced hyperpigmentation model of B16F10 murine melanoma cells. Results showed that α-MSH stimulation significantly increased tyrosinase (TYR) and melanin production, which were significantly downregulated by Q3G treatment. The treatment with Q3G suppressed the transcriptional and protein expressions of melanogenesis-related enzymes TYR, tyrosinase related protein-1 (TRP-1), and TRP-2, along with the melanogenic transcription factor microphthalmia-associated transcription factor (MITF) in B16F10 cells. It was shown that Q3G downregulated MITF expression and suppressed its transcriptional activity by inhibiting the cAMP-dependent protein kinase A (PKA)-mediated activation of CREB and GSK3β. In addition, MAPK-regulated MITF activation signaling was also involved in the inhibition of melanin production by Q3G. The results suggest that the anti-melanogenic properties of Q3G rationalize further studies in vivo to confirm its action mechanism and consequent utilization as a cosmetic ingredient against hyperpigmentation.

From Lactose to Alkyl Galactoside Fatty Acid Esters as Non-Ionic Biosurfactants: A Two-Step Enzymatic Approach to Cheese Whey Valorization

A library of alkyl galactosides was synthesized to provide the "polar head" of sugar fatty acid esters to be tested as non-ionic surfactants. The enzymatic transglycosylation of lactose resulted in alkyl β-D-galactopyranosides, whereas the Fischer glycosylation of galactose afforded isomeric mixtures of α- and β-galactopyranosides and α- and β-galactofuranosides. n-Butyl galactosides from either routes were enzymatically esterified with palmitic acid, used as the fatty acid "tail" of the surfactant, giving the corresponding n-butyl 6-O-palmitoyl-galactosides. Measurements of interfacial tension and emulsifying properties of n-butyl 6-O-palmitoyl-galactosides revealed that the esters of galactopyranosides are superior to those of galactofuranosides, and that the enantiopure n-butyl 6-O-palmitoyl-β-D-galactoside, prepared by the fully enzymatic route, leads to the most stable emulsion. These results pave the way to the use of lactose-rich cheese whey as raw material for the obtainment of bio-based surfactants.

Expanding the scope of stereoselective α-galactosylation using glycosyl chlorides

Recently, we reported that silver(I) oxide mediated Koenigs-Knorr glycosylation reaction can be dramatically accelerated in the presence of catalytic acid additives. We have also investigated how well this reaction works in application to differentially protected galactosyl bromides. Reported herein is the stereoselective synthesis of α-galactosides with galactosyl chlorides as glycosyl donors. Chlorides are easily accessible, stable, and can be efficiently activated for glycosylation. In this application, the most favorable reactions conditions comprised cooperative Ag2SO4 and Bi(OTf)3 promoter system.

The Blood-Cerebrospinal Fluid Barrier Features Different Permeability to Cyanidin-3-galactoside and Cyanidin-3-diglucoside-5-glucoside and Their Metabolites Circulating in Blood

Previous studies have demonstrated the penetration of anthocyanins through the blood-cerebrospinal fluid barrier (BCSF barrier) after intraruminal administration of chokeberry and red cabbage preparation to sheep. However, they have failed to explain which food anthocyanin forms are more capable of crossing the BCSF barrier. Thus, this study aim was to verify the ability of cyanidin 3-galactoside (Cy3gal, main chokeberry anthocyanin) and cyanidin 3-diglucoside-5-glucoside (Cy3diG5G, main red cabbage anthocyanin) to cross the BCSF barrier on the sheep model (n = 16) after intravenous administration (to exclude the influence of gastrointestinal processes) of preparations containing these compounds. The micro-HPLC-MS/MS analysis showed that, after intravenous administration, anthocyanins penetrated the BCSF barrier and that the penetration potential of Cy3gal derivatives (6.73%) was higher than that of Cy3diG5G derivatives (6.10%), suggesting the observed differences to be largely due to the type and number of substituents as well as the size of the molecule.

Identification and Quantification of Anthocyanin and Catechin Compounds in Purple Tea Leaves and Flakes

Tea is the first most popular beverage worldwide and is available in several selections such as black (fully oxidized), Oolong (partially oxidized) and green (non-oxidized), in addition to purple tea, an emerging variety derived from the same tea plant (Camellia sinensis). This study investigated purple tea leaves (non-oxidized) and flakes (water extractable) to thoroughly identify their composition of anthocyanins and catechins and to study the effect of a water extraction process on their compositional properties in comparison with green tea. Anthocyanin and catechin compounds were separated and quantified using UPLC, and their identity was confirmed using LC-MS/MS in positive and negative ionization modes. Delphinidin was the principal anthocyaninidin in purple tea, while cyanidin came in second. The major anthocyanin pigments in purple tea were delphinidin-coumaroyl-hexoside followed by delphinidin-3-galactoside and cyanidin-coumaroyl-hexoside. The water extraction process resulted in substantial reductions in anthocyanins in purple tea flakes. There were no anthocyanin compounds detected in green tea samples. Both purple and green tea types were rich in catechins, with green tea containing higher concentrations than purple tea. The main catechin in purple or green tea was epigallocatechin gallate (EGCG) followed by either epicatechin gallate (ECG) or epigallocatechin (EGC), subject to tea type. The extraction process increased the concentration of catechins in both purple and green tea flakes. The results suggest that purple tea holds promise in making healthy brews, natural colorants and antioxidants and/or functional ingredients for beverages, cosmetics and healthcare industries due to its high content of anthocyanins and catechins.

Far-red Fluorescent Senescence-associated β-Galactosidase Probe for Identification and Enrichment of Senescent Tumor Cells by Flow Cytometry

Cellular senescence is a state of proliferative arrest induced by biological damage that normally accrues over years in aging cells but may also emerge rapidly in tumor cells as a response to damage induced by various cancer treatments. Tumor cell senescence is generally considered undesirable, as senescent cells become resistant to death and block tumor remission while exacerbating tumor malignancy and treatment resistance. Therefore, the identification of senescent tumor cells is of ongoing interest to the cancer research community. Various senescence assays exist, many based on the activity of the well-known senescence marker, senescence-associated beta-galactosidase (SA-β-Gal). Typically, the SA-β-Gal assay is performed using a chromogenic substrate (X-Gal) on fixed cells, with the slow and subjective enumeration of "blue" senescent cells by light microscopy. Improved assays using cell-permeant, fluorescent SA-β-Gal substrates, including C12-FDG (green) and DDAO-Galactoside (DDAOG; far-red), have enabled the analysis of living cells and allowed the use of high-throughput fluorescent analysis platforms, including flow cytometers. C12-FDG is a well-documented probe for SA-β-Gal, but its green fluorescent emission overlaps with intrinsic cellular autofluorescence (AF) that arises during senescence due to the accumulation of lipofuscin aggregates. By utilizing the far-red SA-β-Gal probe DDAOG, green cellular autofluorescence can be used as a secondary parameter to confirm senescence, adding reliability to the assay. The remaining fluorescence channels can be used for cell viability staining or optional fluorescent immunolabeling. Using flow cytometry, we demonstrate the use of DDAOG and lipofuscin autofluorescence as a dual-parameter assay for the identification of senescent tumor cells. Quantitation of the percentage of viable senescent cells is performed. If desired, an optional immunolabeling step may be included to evaluate cell surface antigens of interest. Identified senescent cells can also be flow cytometrically sorted and collected for downstream analysis. Collected senescent cells can be immediately lysed (e.g., for immunoassays or 'omics analysis) or further cultured.

Isolation and Identification of an α-Galactosidase-Producing Lactosphaera pasteurii Strain and Its Enzymatic Expression Analysis

α-Galactosidase (EC 3.2.1.22) refers to a group of enzymes that hydrolyze oligosaccharides containing α-galactoside-banded glycosides, such as stachyose, raffinose, and verbascose. These enzymes also possess great potential for application in sugar production, and in the feed and pharmaceutical industries. In this study, a strain of Lactosphaera pasteurii (WHPC005) that produces α-galactosidase was identified from the soil of Western Hunan, China. It was determined that the optimal temperature and pH for this α-galactosidase were 45 °C and 5.5, respectively. The activity of α-galactosidase was inhibited by K⁺, Al³⁺, Fe³⁺, fructose, sucrose, lactose, galactose, SDS, EDTA, NaCl, and (NH₄)₂SO₄, and enhanced by Ca²⁺, Fe²⁺, Mn², Zn²⁺, glucose, and raffinose. The optimal inducer was raffinose, and the optimal induction concentration was 30 μmol/L. The α-galactosidase gene was cloned using random fragment cloning methods. Sequence analysis demonstrated that the open reading frame of the α-galactosidase gene was 1230 bp, which encodes a putative protein of 409 amino acids in length. Bioinformatics analysis showed that the isoelectric point and molecular weight of this α-galactosidase were 4.84 and 47.40 kD, respectively. Random coils, alpha helixes, and beta turns were observed in its secondary structure, and conserved regions were found in the tertiary structure of this α-galactosidase. Therefore, this α-galactosidase-producing bacterial strain has the potential for application in the feed industry.

Composition and antioxidant activity of anthocyanins from Aronia melanocarpa extracted using an ultrasonic-microwave-assisted natural deep eutectic solvent extraction method

A time-saving, efficient, and environmentally friendly ultrasonic-microwave-assisted natural deep eutectic solvent (UMAE-NADES) extraction method was developed for the extraction of anthocyanins from Aronia melanocarpa. Eight different natural eutectic solvents were screened initially, and choline chloride-glycerol was selected as the extraction solvent. The extraction conditions were optimized using the response surface methodology, and the extraction rate of anthocyanins was higher than those achieved using the traditional ethanol method, natural deep eutectic solvent extraction method, and ultrasonic-microwave-assisted ethanol method. Six anthocyanins, including cyanidin-3-O-galactoside, cyanidin-3-O-glucoside, cyanidin-3-O-arabinoside, cyanidin-3-O-xyloside, cyanidin-3,5-O-dihexoside, and the dimer of cyanidin-hexoside were identified and extracted at a purity of 448.873 mg/g using high performance liquid chromatography-mass spectrometry (HPLC-MS). The compounds extracted using UMAE-NADES had higher antioxidant capacities than those extracted by the other three methods. The UMAE-NADES demonstrated significant efficiency toward the extraction of bioactive substances and has potential utility in the food and pharmaceutical industries.

Fungal Secondary Metabolite Exophillic Acid Selectively Inhibits the Entry of Hepatitis B and D Viruses

Current anti-hepatitis B virus (HBV) drugs are suppressive but not curative for HBV infection, so there is considerable demand for the development of new anti-HBV agents. In this study, we found that fungus-derived exophillic acid inhibits HBV infection with a 50% maximal inhibitory concentration (IC50) of 1.1 µM and a 50% cytotoxic concentration (CC50) of >30 µM in primary human hepatocytes. Exophillic acid inhibited preS1-mediated viral attachment to cells but did not affect intracellular HBV replication. Exophillic acid appears to target the host cells to reduce their susceptibility to viral attachment rather than acting on the viral particles. We found that exophillic acid interacted with the HBV receptor, sodium taurocholate cotransporting polypeptide (NTCP). Exophillic acid impaired the uptake of bile acid, the original function of NTCP. Consistent with our hypothesis that it affects NTCP, exophillic acid inhibited infection with HBV and hepatitis D virus (HDV), but not that of hepatitis C virus. Moreover, exophillic acid showed a pan-genotypic anti-HBV effect. We thus identified the anti-HBV/HDV activity of exophillic acid and revealed its mode of action. Exophillic acid is expected to be a potential new lead compound for the development of antiviral agents.

Cyanidin 3-O-β-Galactoside Alleviated Cognitive Impairment in Mice by Regulating Brain Energy Metabolism During Aging

Metabolic disorder, which commonly happens among senile people worldwide, is an important sign of aging. The early symptoms of neurodegenerative diseases include a decrease in energy metabolism and mitochondrial dysfunction. Comparably, early dietary intervention may be more effective in preventing or delaying brain aging, owing to its role in regulating metabolism. Polyphenol intake has shown its potential in preventing Alzheimer's disease. However, whether there are close connections between polyphenols and the energy metabolism of the brain during aging remains unclear. This study sought to evaluate whether cyanidin 3-O-β-galactoside from black chokeberry (Aronia melanocarpa (Michx.) Elliott) has positive effects on energy metabolism, as well as cognitive function in aging mice. Intragastrical administration of cyanidin 3-O-β-galactoside (25 and 50 mg/kg/day) for 8 weeks effectively alleviated the decline in brain glucose uptake (decline rate 18.29% versus 1.05%, 7.63%) of aging mice. Moreover, cyanidin 3-O-β-galactoside also alleviated neuronal damage in the hippocampus (number of neurons 212.33 ± 16.19 versus 285.33 ± 29.53, 301.67 ± 10.07; p < 0.05) and cortex (number of neurons 82.00 ± 4.58 versus 111.67 ± 6.51, 112.00 ± 1.00; p < 0.05). Furthermore, cyanidin 3-O-β-galactoside reduced β-amyloid load in the brain and significantly increased the crossing-platform number (0.92 ± 1.11 versus 1.83 ± 0.68, 2.08 ± 0.58; p < 0.05) in the Morris water maze test. We further determined that protein kinase B (AKT) might be the target of cyanidin 3-O-β-galactoside, which played a beneficial role in controlling the energy metabolism of the brain. These results suggested that early intervention of anthocyanins could promote neuroprotection under the challenge of brain energy metabolism.

Functions and Inhibition of Galectin-7, an Emerging Target in Cellular Pathophysiology

Galectin-7 is a soluble unglycosylated lectin that is able to bind specifically to β-galactosides. It has been described to be involved in apoptosis, proliferation and differentiation, but also in cell adhesion and migration. Several disorders and diseases are discussed by covering the aforementioned biological processes. Structural features of galectin-7 are discussed as well as targeting the protein intracellularly or extracellularly. The exact molecular mechanisms that lie behind many biological processes involving galectin-7 are not known. It is therefore useful to come up with chemical probes or tools in order to obtain knowledge of the physiological processes. The objective of this review is to summarize the roles and functions of galectin-7 in the human body, providing reasons why it is necessary to design inhibitors for galectin-7, to give the reader structural insights and describe its current inhibitors.

Effect of product partition on the synthesis of butyl-β-D-galactoside from Aspergillus oryzae

The effect of donor substrate and products partitioning on the performance of butyl-β-galactoside synthesis with Aspergillus oryzae β-galactosidase was studied. Firstly, the partition coefficient of the donor substrate (lactose) and the reaction products (glucose, galactose and butyl-β-galactoside) were determined in the aqueous and organic phases of the reaction medium. In the temperature range studied (30 to 50 °C), butyl β-galactoside was roughly 130 and 30-fold more soluble in the organic phase than lactose and the monosaccharides, respectively. Afterward, the effect of the 1-butanol/ aqueous phase ratio (α) on the reaction was evaluated in the range from 0.25 to 4. Results show that higher values of α reduce the incidence of secondary hydrolysis by favoring the extraction of butyl-β-galactoside into the organic phase where it is not hydrolyzed, leading to higher yields. Also, major interfacial properties for butyl-β-galactoside were determined at 25 °C.

CsUGT78A15 catalyzes the anthocyanidin 3-O-galactoside biosynthesis in tea plants

Anthocyanins are a group of natural water-soluble pigments in plants that contribute to the pink-purple color of a range of tissues. Because anthocyanins have various biological activities in human health, there is great research interest in the development of anthocyanin-rich foods and beverages, including purple shoot tea. Anthocyanidin 3-O-galactosides have been identified as one of the main anthocyanin components in purple shoot tea, but the enzyme responsible for their biosynthesis remains unclear. UDP-galactose anthocyanidin 3-O-galactosyltransferase (UA3GalT) is presumed to catalyze the galactosylation of anthocyanidin. Therefore, we assayed the UA3GalT activity in five tea samples with varying degrees of purple color and found that its activity was strongly positively correlated (r = 0.929, p < 0.05) with anthocyanin content. Phylogenetic analysis and sequence alignment suggested that CsUGT78A15 encoded a UA3GalT enzyme. Enzymatic assays indicated that rCsUGT78A15 could catalyze the synthesis of cyanidin 3-O-galactoside and delphinidin 3-O-galactoside using UDP-galactose as a sugar donor, and it showed higher catalytic efficiency towards delphinidin than cyanidin. These results indicate that CsUGT78A15 acts as a UA3GalT in vitro. Subcellular localization showed that CsUGT78A15 was located in the endoplasmic reticulum (ER) and nucleus, consistent with the location of anthocyanin synthesis. Transient overexpression of CsUGT78A15 in the fruit of mature 'Granny Smith' apples showed that the upregulation of CsUGT78A15 promoted cyanidin 3-O-galactoside accumulation in apple skins. These results suggested that CsUGT78A15 could catalyze galactosylation of anthocyanidins in planta. Our findings provide insight into the biosynthesis of anthocyanins in tea plants.

Effect of broad-spectrum biofilm inhibitor raffinose, a plant galactoside, on the inhibition of co-culture biofilm on the microfiltration membrane

A membrane bioreactor (MBR) integrates process such as membrane filtration and biological treatment of activated sludge. However, organic, inorganic and biological matters cause membrane fouling, which seriously affects membrane performance. The goal of this study was to evaluate the biofouling inhibition capacity of raffinose during the MBR process. The results showed that 0-1,000 μM raffinose significantly reduced the formation of the P. aeruginosa and S. aureus co-culture biofilm by about 25-52 % in a concentration-dependent manner. In addition, the effect of raffinose on the microfiltration membrane biofilm was tested in a flow reactor and lab-scale MBR unit. The results showed that the co-culture biofilm and transmembrane pressure were decreased by raffinose treatment compared to those by furanone C-30 treatment. These results clearly demonstrated that raffinose, broad-spectrum biofilm inhibitor, inhibits biofilm formation in mixed cultures and could be used to mitigate biofouling in MBR processes.

Non-primate Lentiviral Vector Administration in the TMJ

Gene therapy is emerging as a novel treatment method for the management of temporomandibular joint disorders. The aim of this investigation was to study the effects of lentiviral vectors on the temporomandibular joint. Consequently, we injected into the articular joint space a defective feline immunodeficiency virus capable of infecting dividing as well as terminally differentiated cells with the reporter gene lacZ, the expression of which was studied by means of PCR, X-gal histochemistry, and β-galactosidase immunocytochemistry. Our results showed successful transduction of hard and soft tissues of the temporomandibular joint. Interestingly, a subset of primary sensory neurons of the ipsilateral trigeminal ganglion also stained positive for the reporter gene, presumably following uptake of the lentiviral vector by peripheral nerve fibers and retrograde transport to the nucleus. These findings suggest that lentiviral vectors can potentially serve as a platform for the transfer of anti-nociceptive genes for the management of temporomandibular joint pain.

[Effects of lyophilized on the biological activities of lentiviral vector of bone morphogenetic protein 2]

PURPOSE

To investigate the influence of lyophilization on the biological activity of recombinant lentiviral vectors of bone morphogenetic protein 2(BMP-2).

METHODS

Recombinant lenti-BMP-2 was constructed. lenti-BMP-2 was transfected with rat bone marrow stromal cells (BMSCs) by multiplicity infection (MOI) of 10, 25, 50, 100, 200. The infection efficiency was observed by X-gal staining. Under suitable conditions, the lenti-BMP-2 and 10% trehalose ratio of lyophilized protective agent was mixed into the lyophilization form. Before and after lyophilization, the effect of lenti-BMP-2 on the proliferation of BMSCs was evaluated by MTS assay. The expression of BMP-2 protein in the cells of lyophilized lenti-BMP-2 was detected by ELISA method. The expression of Runx-2, OCN, Col1 and OPN in BMSCs was detected by real-time PCR after transfection of lyophilized lenti-BMP-2. SPSS13.0 software package was used for statistical analysis.

RESULTS

X-gal staining showed an MOI of 100 pfu/cell, and stable transfection efficiency. Before and after lyophilization, no significant change was observed in regard to the effect of lyophilized lenti-BMP-2 on BMSCs proliferation (P>0.05). ELISA method showed that BMSCs transfected by lyophilized lenti-BMP-2 could express BMP-2 protein continuously and stably at a high level. Before and after lyophilization, the result of real-time PCR showed that no significant difference in the expression of OPN,Col1,OCN and Runx-2 in BMSCs (P>0.05).

CONCLUSIONS

Lyophilized lenti-BMP-2 with trehalose can maintain high activity for a long time as an effective and reliable storage method.

Cyanobacterial Diversity in Biological Soil Crusts along a Precipitation Gradient, Northwest Negev Desert, Israel

Cyanobacteria occur worldwide but play an important role in the formation and primary activity of biological soil crusts (BSCs) in arid and semi-arid ecosystems. The cyanobacterial diversity in BSCs of the northwest Negev desert of Israel was surveyed at three fixed sampling stations situated along a precipitation gradient in the years 2010 to 2012. The three stations also are characterized by marked differences in soil features such as soil carbon, nitrogen, or electrical conductivity. The cyanobacterial biodiversity was analyzed by sequencing inserts of clone libraries harboring partial 16S rRNA gene sequences obtained with cyanobacteria-specific primers. Filamentous, non-diazotrophic strains (subsection III), particularly Microcoleus-like, dominated the cyanobacterial community (30% proportion) in all years. Specific cyanobacterial groups showed increased (e.g., Chroococcidiopsis, Leptolyngbya, and Nostoc strains) or decreased (e.g., unicellular strains belonging to the subsection I and Scytonema strains) abundances with declining water availability at the most arid, southern station, whereas many cyanobacterial strains were frequently found in the soils of all three stations. The cyanobacterial diversity at the three sampling stations appears dependent on the available precipitation, whereas the differences in soil chemistry were of lower importance.

Methods for Detection of Ptc1-Driven LacZ Expression in Adult Mouse Skin

The Ptc-lacZ reporter mice are a highly utilized animal model for studying both normal tissue development and cancer. Identifying cell specific activation of Hedgehog (Hh) signaling is essential to understand the effects of this critical and complex signaling pathway. β-gal detection in tissues can be difficult, with various staining procedures yielding differential results. Thus, detailed information on staining protocols is essential for determining the ideal method for a given study. Furthermore, immunohistochemical staining of X-Gal stained tissues can provide further insight into other key players in Hh signaling activation.

Self-regulated left-right asymmetric expression of Pitx2c in the developing mouse limb

The transcription factor Pitx2c is expressed in primordial visceral organs in a left-right (L-R) asymmetric manner and executes situs-specific morphogenesis. Here we show that Pitx2c is also L-R asymmetrically expressed in the developing mouse limb. Human PITX2c exhibits the same transcriptional activity in the mouse limb. The asymmetric expression of Pitx2c in the limb also exhibits dorsal-ventral and anterior-posterior polarities, being confined to the posterior-dorsal region of the left limb. Left-sided Pitx2c expression in the limb is regulated by Nodal signaling through a Nodal-responsive enhancer. Pitx2c is expressed in lateral plate mesoderm (LPM)-derived cells in the left limb that contribute to various limb connective tissues. The number of Pitx2c(+) cells in the left limb was found to be negatively regulated by Pitx2c itself. Although obvious defects were not apparent in the limb of mice lacking asymmetric Pitx2c expression, Pitx2c may regulate functional L-R asymmetry of the limb.

An arterial-specific enhancer of the human endothelin converting enzyme 1 (ECE1) gene is synergistically activated by Sox17, FoxC2, and Etv2

Endothelin-converting enzyme-1 (Ece-1), a crucial component of the Endothelin signaling pathway, is required for embryonic development and is an important regulator of vascular tone, yet the transcriptional regulation of the ECE1 gene has remained largely unknown. Here, we define the activity and regulation of an enhancer from the human ECE1 locus in vivo. The enhancer identified here becomes active in endothelial progenitor cells shortly after their initial specification and is dependent on a conserved FOX:ETS motif, a composite binding site for Forkhead transcription factors and the Ets transcription factor Etv2, for activity in vivo. The ECE1 FOX:ETS motif is bound and cooperatively activated by FoxC2 and Etv2, but unlike other described FOX:ETS-dependent enhancers, ECE1 enhancer activity becomes restricted to arterial endothelium and endocardium by embryonic day 9.5 in transgenic mouse embryos. The ECE1 endothelial enhancer also contains an evolutionarily-conserved, consensus SOX binding site, which is required for activity in transgenic mouse embryos. Importantly, the ECE1 SOX site is bound and activated by Sox17, a transcription factor involved in endothelial cell differentiation and an important regulator of arterial identity. Moreover, the ECE1 enhancer is cooperatively activated by the combinatorial action of FoxC2, Etv2, and Sox17. Although Sox17 is required for arterial identity, few direct transcriptional targets have been identified in endothelial cells. Thus, this work has important implications for our understanding of endothelial specification and arterial subspecification.

A thin-layer chromatography autographic method for the detection of inhibitors of the Salmonella PhoP-PhoQ regulatory system

INTRODUCTION

The PhoP-PhoQ system from Salmonella enterica serovar Typhimurium controls the expression of factors that are critical for the bacterial entry into host cells and the bacterial intramacrophage survival. Therefore it constitutes an interesting target to search for compounds that would control Salmonella virulence. Localisation of such compounds in complex matrixes could be facilitated by thin-layer chromatography (TLC) bioautography.

OBJECTIVE

To develop a TLC bioautography to detect inhibitors of the PhoP-PhoQ regulatory system in complex matrixes.

METHODS

The TLC plates were covered by a staining solution containing agar, Luria-Bertani medium, 5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside (X-gal), kanamycin and a S. typhimurium strain that harbours a reporter transcriptional lacZ-fusion to an archetypal PhoP-activated gene virK. After solidification, the plate was incubated at 37°C for 16 h.

RESULTS

A bioautographic assay suitable for the localisation of inhibitors of the PhoP-PhoQ system activity in S. enterica serovar Typhimurium present in a complex matrix is described. The assay was used to analyse a series of hydrolysed extracts prepared by alkaline treatment of crude plant extracts. Bioassay-guided analysis of the fractions by NMR spectroscopy and MS led to the identification of linolenic and linoleic acids as inhibitory input signals of the PhoP-PhoQ system.

CONCLUSION

A practical tool is introduced that facilitates detection of inhibitors of the Salmonella PhoP-PhoQ regulatory system. The assay convenience is illustrated with the identification of the first naturally occurring organic compounds that down-regulate a PhoP-PhoQ regulatory system from a hydrolysed extract.

Predicting the spatiotemporal dynamics of hair follicle patterns in the developing mouse

Reaction-diffusion models have been used as a paradigm for describing the de novo emergence of biological patterns such as stripes and spots. In many organisms, these initial patterns are typically refined and elaborated over the subsequent course of development. Here we study the formation of secondary hair follicle patterns in the skin of developing mouse embryos. We used the expression of sex-determining region Y box 2 to identify and distinguish the primary and secondary hair follicles and to infer the spatiotemporal dynamics of the follicle formation process. Quantitative analysis of the specific follicle patterns observed reveals a simple geometrical rule governing the formation of secondary follicles, and motivates an expansion-induction (EI) model in which new follicle formation is driven by the physical growth of the embryo. The EI model requires only one diffusible morphogen and provides quantitative, accurate predictions on the relative positions and timing of secondary follicle formation, using only the observed configuration of primary follicles as input. The same model accurately describes the positions of additional follicles that emerge from skin explants treated with an activator. Thus, the EI model provides a simple and robust mechanism for predicting secondary space-filling patterns in growing embryos.

Inducible, tightly regulated and non-leaky neuronal gene expression in mice

The Tetracycline (Tet)-controlled inducible system is the most widely used reversible system for transgene expression in mice with over 500 lines created to date. Although this system has been optimized over the years, it still has limitations such as residual transgene expression when turned off, referred to as leakiness. Here, we present a series of new Tet-OFF transgenic mice based on the second generation tetracycline-responsive transactivator system. The tTA-Advanced (tTA2(S)) is expressed under control of the neuron-specific Thy1.2 promoter (Thy-OFF), to regulate expression in the mouse brain. In addition, we generated a lacZ reporter line, utilizing the P tight Tet-responsive promoter (P(tight)-lacZ), to test our system. Two Thy-OFF transgenic lines displaying two distinct patterns of expression were selected. Oral doxycycline treatment of Thy-OFF/P tight-lacZ mice demonstrated tight transgene regulation with no leak expression. These new Thy-OFF mice are valuable for studies in a broad range of neurodegenerative diseases such as Alzheimer's disease and related forms of dementia, where control of transgene expression is critical to understanding mechanisms underlying the disease. Furthermore, P tight-lacZ reporter mice may be widely applicable.

[Double-mutated oncolytic adenovirus combined with gemcitabine for treating an orthotopic nude mouse model of bladder cancer]

OBJECTIVE

To investigate the therapeutic efficacy of double-mutated oncolytic adenovirus AxdAdB-3 in combination with gemcitabine for treating bladder cancer in an orthotopic nude mouse model.

METHODS

The susceptibility to the adenovirus was evaluated in bladder cancer cell lines YTS-1, T24, 5637 and KK47, and normal cell lines HCV29 and WI38. The cells were infected with AxCAlacZ and stained with 5-bromo-4-chloro-3-indolyl-β-galactoside (X-Gal). Immunostaining against adenoviral hexon protein was performed to determine the selective replication of AxdAdB-3 in the cancer cells. Flow cytometry was used to determine the YTS-1 cells in S phase of cell cycle after adenovirus infection. Cell viability after AxdAdB-3 and/or gemcitabine was measured by CCK-8 assay. Orthotopic bladder cancer model was established in nude mice, and the inhibitory efficacy of intravesical instillation therapy with AxdAdB-3 or/and gemcitabine was assessed.

RESULTS

Gene transduction efficiency was different among the cell lines, and correlated with expression of CAR. 5637 and KK47 cells with high expression of CAR were more susceptible to the adenovirus, whereas YTS-1 and T24 cells with little CAR expression were resistant to adenoviral infection. Immunostaining showed that the expression levels of hexon protein varied among the cell lines. Normal cells infected with AxdAdB-3 expressed little hexon protein. The proportion of S-phase cells was (39 ± 3) % and (49 ± 5) % in the AxCAlacZ- and AxdAdB-3-infected bladder cancer cells, respectively. AxdAdB-3 effectively induced S-phase entry of cell cycle (P < 0.05). AxdAdB-3 combined with gemcitabine significantly inhibited the growth of bladder cancer cell lines. In vivo, the mean weight of the bladder tumors in mice treated with intravesical instillation of AxCAlacZ, gemcitabine, AxdAdB-3, and AxdAdB-3 + gemcitabine were 400.6, 126.4, 82. 0, 40.4 mg, respectively. Either AxdAdB-3 (P < 0.0001) and gemcitabine (P < 0.0001) suppressed the tumor growth in nude mice, and the combination therapy reduced tumors more effectively than either AxdAdB-3 (P < 0.0001) or gemcitabine (P < 0.0001) alone.

CONCLUSIONS

Intravesical instillation therapy with AxdAdB-3 in combination with gemcitabine can effectively inhibit the orthotopic bladder cancer in nude mouse, and further relevant clinical studies are guaranteed.

p∆TubHA4C, a new versatile vector for constitutive expression in Drosophila

Several vectors for gene expression are available in Drosophila, a hub for genetics and genomics innovation. However, the vectors for ubiquitous expression have a complex structure, including coding exons, that makes in-frame cloning of cDNAs very complicated. In this report we describe a new Drosophila expression vector (p∆TubHA4C) for ubiquitous expression of coding sequences under the control of a minimal 0.9 kb promoter of α1 tubulin (α1t). This plasmid was designed to include optimized multiple cloning sites (polylinker) to provide flexibility in cloning strategies. We also added the option of double labeling the expressed proteins with two C-terminal tags, the viral epitope hemagglutinin and a synthetic tetracysteine (4C) tag that binds small fluorescent compounds. This dual tag allows both in situ and biochemical detection of the desired protein. In particular, the new 4C tag technology combines easy fluorescent labeling with small arsenical compounds in live or fixed cells and tissues, while producing minimal alterations to the tagged protein due to its small size. To demonstrate the potent and ubiquitous expression under the control of the ∆Tub promoter, bacterial lacZ was expressed and monitored in cell culture and transgenic flies. We found that the modified 0.9 kb ΔTub promoter induced similar expression levels to the intact 2.6 kb α1t promoter, supporting the inclusion of all critical regulatory elements in the new and flexible ∆TubHA4C vector.

Loss-of-function mutations in SOX10 cause Kallmann syndrome with deafness

Transcription factor SOX10 plays a role in the maintenance of progenitor cell multipotency, lineage specification, and cell differentiation and is a major actor in the development of the neural crest. It has been implicated in Waardenburg syndrome (WS), a rare disorder characterized by the association between pigmentation abnormalities and deafness, but SOX10 mutations cause a variable phenotype that spreads over the initial limits of the syndrome definition. On the basis of recent findings of olfactory-bulb agenesis in WS individuals, we suspected SOX10 was also involved in Kallmann syndrome (KS). KS is defined by the association between anosmia and hypogonadotropic hypogonadism due to incomplete migration of neuroendocrine gonadotropin-releasing hormone (GnRH) cells along the olfactory, vomeronasal, and terminal nerves. Mutations in any of the nine genes identified to date account for only 30% of the KS cases. KS can be either isolated or associated with a variety of other symptoms, including deafness. This study reports SOX10 loss-of-function mutations in approximately one-third of KS individuals with deafness, indicating a substantial involvement in this clinical condition. Study of SOX10-null mutant mice revealed a developmental role of SOX10 in a subpopulation of glial cells called olfactory ensheathing cells. These mice indeed showed an almost complete absence of these cells along the olfactory nerve pathway, as well as defasciculation and misrouting of the nerve fibers, impaired migration of GnRH cells, and disorganization of the olfactory nerve layer of the olfactory bulbs.

Genetic transformation of a clinical (genital tract), plasmid-free isolate of Chlamydia trachomatis: engineering the plasmid as a cloning vector

Our study had three objectives: to extend the plasmid-based transformation protocol to a clinical isolate of C. trachomatis belonging to the trachoma biovar, to provide “proof of principle” that it is possible to “knock out” selected plasmid genes (retaining a replication competent plasmid) and to investigate the plasticity of the plasmid. A recently developed, plasmid-based transformation protocol for LGV isolates of C. trachomatis was modified and a plasmid-free, genital tract C. trachomatis isolate from Sweden (SWFP-) was genetically transformed. Transformation of this non-LGV C. trachomatis host required a centrifugation step, but the absence of the natural plasmid removed the need for plaque purification of transformants. Transformants expressed GFP, were penicillin resistant and iodine stain positive for accumulated glycogen. The transforming plasmid did not recombine with the host chromosome. A derivative of pGFP::SW2 carrying a deletion of the plasmid CDS5 gene was engineered. CDS5 encodes pgp3, a protein secreted from the inclusion into the cell cytoplasm. This plasmid (pCDS5KO) was used to transform C. trachomatis SWFP-, and established that pgp3 is dispensable for plasmid function. The work shows it is possible to selectively delete segments of the chlamydial plasmid, and this is the first step towards a detailed molecular dissection of the role of the plasmid. The 3.6 kb β-galactosidase cassette was inserted into the deletion site of CDS5 to produce plasmid placZ-CDS5KO. Transformants were penicillin resistant, expressed GFP and stained for glycogen. In addition, they expressed β-galactosidase showing that the lacZ cassette was functional in C. trachomatis. An assay was developed that allowed the visualisation of individual inclusions by X-gal staining. The ability to express active β-galactosidase within chlamydial inclusions is an important advance as it allows simple, rapid assays to measure directly chlamydial infectivity without the need for plaquing, fluorescence or antibody staining.

Regulation of neonatal and adult mammalian heart regeneration by the miR-15 family

We recently identified a brief time period during postnatal development when the mammalian heart retains significant regenerative potential after amputation of the ventricular apex. However, one major unresolved question is whether the neonatal mouse heart can also regenerate in response to myocardial ischemia, the most common antecedent of heart failure in humans. Here, we induced ischemic myocardial infarction (MI) in 1-d-old mice and found that this results in extensive myocardial necrosis and systolic dysfunction. Remarkably, the neonatal heart mounted a robust regenerative response, through proliferation of preexisting cardiomyocytes, resulting in full functional recovery within 21 d. Moreover, we show that the miR-15 family of microRNAs modulates neonatal heart regeneration through inhibition of postnatal cardiomyocyte proliferation. Finally, we demonstrate that inhibition of the miR-15 family from an early postnatal age until adulthood increases myocyte proliferation in the adult heart and improves left ventricular systolic function after adult MI. We conclude that the neonatal mammalian heart can regenerate after myocardial infarction through proliferation of preexisting cardiomyocytes and that the miR-15 family contributes to postnatal loss of cardiac regenerative capacity.

Spatiotemporal regulation of an Hcn4 enhancer defines a role for Mef2c and HDACs in cardiac electrical patterning

Regional differences in cardiomyocyte automaticity permit the sinoatrial node (SAN) to function as the leading cardiac pacemaker and the atrioventricular (AV) junction as a subsidiary pacemaker. The regulatory mechanisms controlling the distribution of automaticity within the heart are not understood. To understand regional variation in cardiac automaticity, we carried out an in vivo analysis of cis-regulatory elements that control expression of the hyperpolarization-activated cyclic-nucleotide gated ion channel 4 (Hcn4). Using transgenic mice, we found that spatial and temporal patterning of Hcn4 expression in the AV conduction system required cis-regulatory elements with multiple conserved fragments. One highly conserved region, which contained a myocyte enhancer factor 2C (Mef2C) binding site previously described in vitro, induced reporter expression specifically in the embryonic non-chamber myocardium and the postnatal AV bundle in a Mef2c-dependent manner in vivo. Inhibition of histone deacetylase (HDAC) activity in cultured transgenic embryos showed expansion of reporter activity to working myocardium. In adult animals, hypertrophy induced by transverse aortic constriction, which causes translocation of HDACs out of the nucleus, resulted in ectopic activation of the Hcn4 enhancer in working myocardium, recapitulating pathological electrical remodeling. These findings reveal mechanisms that control the distribution of automaticity among cardiomyocytes during development and in response to stress.

Use of Cre-lox technology to analyze integrin functions in astrocytes

Astrocytes communicate with the vascular endothelium via direct cell-cell contacts as well as a variety of secreted growth factors and extracellular matrix (ECM) proteins. Integrins are heterodimeric cell surface receptors for ECM protein ligands, and many integrin subunits are expressed in astrocytes. Here, we will discuss gene deletion strategies in mice that have deciphered functions for specific integrins in astrocyte-endothelial cell adhesion and signaling. Specifically, we will detail how Cre-lox molecular genetic techniques have revealed important roles for integrin αvβ8 in regulating cerebral blood vessel development and homeostasis. First, we will detail how to generate Cre-lox mutant mouse models that our group and others have used to study αvβ8 integrin in embryonic astroglial progenitors and postnatal astrocytes. Second, we will discuss how viral-delivered Cre can be used to acutely delete integrin genes in astrocytes within defined anatomic regions of the brain. Third, detailed in vivo methods to verify Cre-mediated gene recombination in astrocytes will be presented. Lastly, we will present one experimental strategy to determine how integrin gene deletion affects astrocyte-endothelial cell coupling in the CNS. While this review focuses on the generation and characterization of mice lacking αvβ8 integrin, these experimental strategies can be expanded to analyze other cell adhesion and signaling genes important for astroglial-mediated regulation of blood vessel development and homeostasis.

Separate and distinctive roles for Wnt5a in tongue, lingual tissue and taste papilla development

Although canonical Wnt signaling is known to regulate taste papilla induction and numbers, roles for noncanonical Wnt pathways in tongue and taste papilla development have not been explored. With mutant mice and whole tongue organ cultures we demonstrate that Wnt5a protein and message are within anterior tongue mesenchyme across embryo stages from the initiation of tongue formation, through papilla placode appearance and taste papilla development. The Wnt5a mutant tongue is severely shortened, with an ankyloglossia, and lingual mesenchyme is disorganized. However, fungiform papilla morphology, number and innervation are preserved, as is expression of the papilla marker, Shh. These data demonstrate that the genetic regulation for tongue size and shape can be separated from that directing lingual papilla development. Preserved number of papillae in a shortened tongue results in an increased density of fungiform papillae in the mutant tongues. In tongue organ cultures, exogenous Wnt5a profoundly suppresses papilla formation and simultaneously decreases canonical Wnt signaling as measured by the TOPGAL reporter. These findings suggest that Wnt5a antagonizes canonical Wnt signaling to dictate papilla number and spacing. In all, distinctive roles for Wnt5a in tongue size, fungiform papilla patterning and development are shown and a necessary balance between non-canonical and canonical Wnt paths in regulating tongue growth and fungiform papillae is proposed in a model, through the Ror2 receptor.

Segment-specific regulation of the Drosophila AP-2 gene during leg and antennal development

Segmentation involves subdivision of a developing body part into multiple repetitive units during embryogenesis. In Drosophila and other insects, embryonic segmentation is regulated by genes expressed in the same domain of every segment. Less is known about the molecular basis for segmentation of individual body parts occurring at later developmental stages. The Drosophila transcription factor AP-2 gene, dAP-2, is required for outgrowth of leg and antennal segments and is expressed in every segment boundary within the larval imaginal discs. To investigate the molecular mechanisms generating the segmentally repetitive pattern of dAP-2 expression, we performed transgenic reporter analyses and isolated multiple cis-regulatory elements that can individually or cooperatively recapitulate endogenous dAP-2 expression in different segments of the appendages. We further analyzed an enhancer specific for the proximal femur region which corresponds to the distal-most expression domain of homothorax (hth) in the leg imaginal discs. Hth is known to be responsible for the nuclear localization and, hence, function of the Hox cofactor, Extradenticle (Exd). We show that both Hth and Exd are required for dAP-2 expression in the femur and that a conserved Exd/Hox binding site is essential for enhancer activity. Our loss- and gain-of-function studies further support direct regulation of dAP-2 by Hox proteins and suggest that Hox proteins function redundantly in dAP-2 regulation. Our study reveals that discrete segment-specific enhancers underlie the seemingly simple repetitive expression of dAP-2 and provides evidence for direct regulation of leg segmentation by regional combinations of the proximodistal patterning genes.

Generation of mice with a conditional null allele for Wntless

The Wnt-signaling pathway is necessary in a variety of developmental processes and has been implicated in numerous pathologies. Wntless (Wls) binds to Wnt proteins and facilitates Wnt sorting and secretion. Conventional deletion of Wls results in early fetal lethality due to defects in body axis establishment. To gain insight into the function of Wls in later stages of development, we have generated a conditional null allele. Homozygous germline deletion of Wls confirmed prenatal lethality and failure of embryonic axis formation. Deletion of Wls using Wnt1-cre phenocopied Wnt1 null abnormalities in the midbrain and hindbrain. In addition, conditional deletion of Wls in pancreatic precursor cells resulted in pancreatic hypoplasia similar to that previously observed after conditional β-catenin deletion. This Wls conditional null allele will be valuable in detecting novel Wnt functions in development and disease.

Fos-Tau-LacZ mice reveal sex differences in brainstem c-fos activation in response to mild carbon dioxide exposure

There are sex differences in the neurochemistry of brainstem nuclei that participate in the control of breathing as well as sex differences in respiratory responses to hypoxia. Central chemoreception refers to the detection within the brain of minute changes in carbon dioxide (CO(2)) levels and the subsequent modulation of breathing. Putative central chemoreceptor sites are widespread and include cells located near the ventral surface of the brainstem in the retrotrapezoid nucleus (RTN), in the medullary midline raphe nuclei, and, more dorsally in the medulla, in the nucleus of the solitary tract and in the locus caeruleus at the pontomedullary junction as well as in the fastigial nucleus of the cerebellum. In this study, we ask if the cells that respond to CO(2) differ between the sexes. We used a transgenic mouse with a c-fos promoter driven tau-lacZ reporter construct (FTL) to map the locations of cells in the mouse brainstem and cerebellum that responded to exposure of mice of both sexes to 5% CO(2) or room air (control). X-gal (5-bromo-4-chloro-3-indolyl-beta-d-galactopyranoside) histochemical staining to detect the beta-galactosidase enzyme produced staining in the brains of mice of both sexes in all of the previously identified putative chemoreceptor sites, with the exception of the fastigial nucleus. Notably, the male RTN region contained significantly more x-gal-labeled cells than the female RTN region. In addition to new observations regarding potential sex differences in the retrotrapezoid region, we found the FTL mouse to be a useful tool for identifying cells that respond to the exposure of the whole animal to relatively low concentrations of CO(2).

A combined method of laser capture microdissection and X-Gal histology to analyze gene expression in c-Fos-specific neurons

c-Fos is a member of the activator protein 1 family that regulates transcription of target genes. c-Fos is transiently induced in specific regions of the brain after a variety of external stimuli including learning and memory formation. Analysis of gene expression in c-Fos-expressing cells of the brain may help identify target genes that play important roles in synaptic strength or neuronal morphology. In the present study, we developed a combined method of laser capture microdissection and 5-bromo-4-chloro-3-indoly-beta-D-galactopyranosidase (X-Gal) histology to analyze gene expression in stimulus-induced c-Fos-positive cells. Using transgenic mice carrying a c-fos-lacZ fusion gene, c-Fos-positive cells were easily identified by measuring of beta-galactosidase (beta-Gal) activity. To establish the fidelity of the reporter transgene, the time course of endogenous c-Fos and the c-fos-lacZ transgene expression in the amygdala induced by LiCl administration was investigated by immunohistochemistry and X-Gal staining. LiCl increased the numbers of c-Fos- and beta-Gal-positive cells in the central and basolateral amygdala of the transgenic mice. To ensure that RNA was preserved in X-Gal stained tissue sections, different fixations were examined, with the conclusion that ethanol fixation was best for both RNA preservation and X-Gal staining quality. Finally, in combining X-Gal staining, single-cell LCM and RT-PCR, we confirmed mRNA expression of endogenous c-fos and beta-actin genes in LiCl-induced beta-Gal-positive cells in the CeA, cortex and hippocampus. Combining LCM and transgenic reporter genes provides a powerful tool with which to investigate tissue- or cell-specific gene expression.

Distribution of EphA5 receptor protein in the developing and adult mouse nervous system

The EphA5 receptor tyrosine kinase plays key roles in axon guidance during development. However, the presence of EphA5 protein in the nervous system has not been fully characterized. To examine EphA5 localization better, mutant mice, in which the EphA5 cytoplasmic domain was replaced with beta-galactosidase, were analyzed for both temporal and regional changes in the distribution of EphA5 protein in the developing and adult nervous system. During embryonic development, high levels of EphA5 protein were found in the retina, olfactory bulb, cerebral neocortex, hippocampus, pretectum, tectum, cranial nerve nuclei, and spinal cord. Variations in intensity were observed as development proceeded. Staining of pretectal nuclei, tectal nuclei, and other areas of the mesencephalon became more diffuse after maturity, whereas the cerebral neocortex gained more robust intensity. In the adult, receptor protein continued to be detected in many areas including the olfactory nuclei, neocortex, piriform cortex, induseum griseum, hippocampus, thalamus, amygdala, hypothalamus, and septum. In addition, EphA5 protein was found in the claustrum, stria terminalis, barrel cortex, and striatal patches, and along discrete axon tracts within the corpus callosum of the adult. We conclude that EphA5 function is not limited to the developing mouse brain and may play a role in synaptic plasticity in the adult.

The FERM protein Epb4.1l5 is required for organization of the neural plate and for the epithelial-mesenchymal transition at the primitive streak of the mouse embryo

During early mouse development, a single-layered epithelium is transformed into the three germ layers that are the basis of the embryonic body plan. Here we describe an ENU-induced mutation, limulus (lulu), which disrupts gastrulation and the organization of all three embryonic germ layers. Positional cloning and analysis of additional alleles show that lulu is a null allele of the FERM-domain gene erythrocyte protein band 4.1-like 5 (Epb4.1l5). During gastrulation, some cells in lulu mutants are trapped in the primitive streak at an intermediate stage of the epithelial-mesenchymal transition; as a result, the embryos have very little paraxial mesoderm. Epithelial layers of the later lulu embryo are also disrupted: definitive endoderm is specified but does not form a gut tube, and the neural plate is broad and forms ectopic folds rather than closing to make the neural tube. In contrast to zebrafish and Drosophila, in which orthologs of Epb4.1l5 control the apical localization and activity of Crumbs proteins, mouse Crumbs proteins are localized normally to the apical surface of the lulu mutant epiblast and neural plate. However, the defects in both the lulu primitive streak and neural plate are associated with disruption of the normal organization of the actin cytoskeleton. We propose that mouse Lulu (Epb4.1l5) helps anchor the actin-myosin contractile machinery to the membrane to allow the dynamic rearrangements of epithelia that mediate embryonic morphogenesis.

Therapeutic benefits by human mesenchymal stem cells (hMSCs) and Ang-1 gene-modified hMSCs after cerebral ischemia

Transplantation of human mesenchymal stem cells (hMSCs) prepared from adult bone marrow has been reported to ameliorate functional deficits after cerebral artery occlusion in rats. Although several hypotheses to account for these therapeutic effects have been suggested, current thinking is that both neuroprotection and angiogenesis are primarily responsible. In this study, we compared the effects of hMSCs and angiopoietin-1 gene-modified hMSCs (Ang-hMSCs) intravenously infused into rats 6 h after permanent middle cerebral artery occlusion. Magnetic resonance imaging and histologic analyses revealed that rats receiving hMSCs or Ang-hMSCs exhibited comparable reduction in gross lesion volume as compared with the control group. Although both cell types indeed improved angiogenesis near the border of the ischemic lesions, neovascularization and regional cerebral blood flow were greater in some border areas in Ang-hMSC group. Both hMSC- and Ang-hMSC-treated rats showed greater improved functional recovery in the treadmill stress test than did control rats, but the Ang-hMSC group was greater. These results indicate the intravenous administration of genetically modified hMSCs to express angiopoietin has a similar effect on reducing lesion volume as hMSCs, but the Ang-hMSC group showed enhanced regions of increased angiogenesis at the lesion border, and modest additional improvement in functional outcome.

Response of olfactory axons to loss of synaptic targets in the adult mouse

Glomerular convergence has been proposed to rely on interactions between like olfactory axons, however topographic targeting is influenced by guidance molecules encountered in the olfactory bulb. Disruption of these cues during development misdirects sensory axons, however little is known about the role of bulb-derived signals in later life, as new axons arise during turnover of the olfactory sensory neuron (OSN) population. To evaluate the contribution of bulb neurons in maintaining topographic projections in adults, we ablated them with N-methyl-d-aspartate (NMDA) in P2-IRES-tauLacZ mice and examined how sensory axons responded to loss of their postsynaptic partners. NMDA lesion eliminated bulb neurons without damage to sensory axons or olfactory ensheathing glia. P2 axons contained within glomeruli at the time of lesion maintained convergence at these locations; there was no evidence of compensatory growth into the remnant tissue. Delayed apoptosis of OSNs in the target-deprived epithelium led to declines in P2 neuron number as well as the gradual atrophy, and in some cases complete loss, of P2 glomeruli in lesioned bulbs by 3 weeks. Increased cell proliferation in the epithelium partially restored the OSN population, and by 8 weeks, new P2 axons distributed within diverse locations in the bulb remnant and within the anterior olfactory nucleus. Prior studies have suggested that initial development of olfactory topography does not rely on synapse formation with target neurons, however the present data demonstrate that continued maintenance of the sensory map requires the presence of sufficient numbers and/or types of available bulbar synaptic targets.

The effect of physico-chemical parameters and chemical compounds on the activity of beta-d-galactosidase (B-GAL), a marker enzyme for indicator microorganisms in water

The presence of coliforms in polluted water was determined enzymatically (in situ) by directly monitoring the activity of beta-d-galactosidase (B-GAL) through the hydrolysis of the yellow chromogenic subtrate, chlorophenol red beta-d-galactopyranoside (CPRG), which produced a red chlorophenol red (CPR) product. The objectives of this study were to monitor the effect of compounds commonly found in the environment and used in water treatment on a B-GAL CPRG assay and to investigate the differences between the environmental B-GAL enzyme and the pure commercial enzyme. Environmental B-GAL was optimally active at pH 7.8. Two temperature optima were observed at 35 and 55 degrees C, respectively. B-GAL activity was strongly inhibited by silver and copper ions. While calcium and ferrous ions at lower concentrations (50-100mgl(-1)) increased the enzyme activity, a reduction was observed at higher concentrations (200mgl(-1)). Sodium hypochlorite, normally used in rural areas to disinfect water gradually decreased B-GAL activity at concentrations between 0 and 5600ppm for both the commercial and environmental enzymes. B-GAL from the environment behaved differently from its commercially available counterpart.