Autism spectrum disorder (ASD) is a developmental disorder characterized by social behavior deficit in childhood without satisfactory medical intervention. Transcutaneous electrical acupoint stimulation (TEAS) is a noninvasive technique derived from acupuncture and has been shown to have similar therapeutic effects in many diseases. Valproic acid- (VPA-) induced ASD is a known model of ASD in rats. The therapeutic efficacy of TEAS was evaluated in the VPA model of ASD in the present study. The offspring of a VPA-treated rat received TEAS in the early life stage followed by a series of examinations conducted in their adolescence. The results show that following TEAS treatment in early life, the social and cognitive ability in adolescence of the offspring of a VPA rat were significantly improved. In addition, the abnormal pain threshold was significantly corrected. Additional studies demonstrated that the dendritic spine density of the primary sensory cortex was decreased with Golgi staining. Results of the transcriptomic study showed that expression of some transcription factors such as the neurotrophic factor were downregulated in the hypothalamus of the VPA model of ASD. The reduced gene expression was reversed following TEAS. These results suggest that TEAS in the early life stage may mitigate disorders of social and recognition ability and normalize the pain threshold of the ASD rat model. The mechanism involved may be related to improvement of synaptic plasticity.

Astragalus membranaceus root has been widely used for repigmentation treatment in vitiligo, but its mechanism is poorly understood. We sought to investigate the effect of astragaloside IV (AS-IV), a main active extract of the Astragalus membranaceus root, on melanin synthesis in normal human epidermal melanocytes (NHEMs) and to elucidate its underlying mechanisms. Melanin content, tyrosinase activity, qPCR, western blot, and immunofluorescence were employed. Specific inhibitors and small interfering RNA were used to investigate the possible pathway. AS-IV stimulated melanin synthesis and upregulated the expression of melanogenesis-related genes in a concentration-dependent manner in NHEMs. AS-IV could activate the aryl hydrocarbon receptor (AhR), and AS-IV-induced melanogenesis was inhibited in si-AhR-transfected NHEMs. In addition, we showed that AS-IV enhanced the phosphorylation of AKT and GSK-3β and nuclear translocation of β-catenin. AS-IV-induced MITF expression upregulation and melanin synthesis were decreased in the presence of β-catenin inhibitor FH353. Furthermore, AhR antagonist CH223191 inhibited the activation of AKT/GSK-3β/β-catenin signaling, whereas the expression of CYP1A1 (marker of AhR activation) was not affected by the AKT inhibitor in AS-IV-exposed NHEMs. Our findings show that AS-IV induces melanogenesis through AhR-dependent AKT/GSK-3β/β-catenin pathway activation and could be beneficial in the therapy for depigmented skin disorders.

Spontaneous intracerebral hemorrhage (ICH) commonly causes secondary hippocampal damage and delayed cognitive impairments, but the mechanisms remain elusive. Here, we sought to identify the molecular mechanisms underlying these hemorrhagic outcomes in a rat autologous blood model of ICH. First, a significant increase in phosphatase and tensin homolog (PTEN) expression was observed in nonhemorrhagic ipsilateral hippocampus. However, systemic administration of PTEN inhibitor BPV or hippocampal injection of PTEN siRNA could prevent hippocampal neuronal injury and cognitive dysfunctions after ICH. Furthermore, we also found that ICH robustly triggered autophagic neuronal death in the ipsilateral hippocampus, but which were strongly reduced by PTEN knockdown. Notably, suppression of autophagy effectively attenuated poststroke hippocampal inflammation, neuronal damage, and cognitive decline, suggesting the beneficial effects of PTEN deletion was associated with autophagy inactivation. Specifically, PTEN antagonized the PI3K/AKT signaling and downstream effector FoxO3a phosphorylation and subsequently enhanced nuclear translocation of FoxO3a to drive proautophagy gene program, but these changes were diminished upon PTEN inhibition. More importantly, lentivirus-mediated FoxO3a overexpression apparently abrogated the antiauotphagy effect of PTEN deletion via enhancing autophagy-related gene (ATG) transcription. Collectively, these results suggest that knockdown of PTEN alleviated progressive hippocampal injury and cognitive deficits by suppression of autophagy induction involving the AKT/FoxO3a/ATG axis after ICH. Thus, this study provides a novel and promising therapeutic target for the treatment of hemorrhagic stroke.

Abstract M cell targeting is one of the critical issues to develop efficient mucosal vaccine design. In this study, peptide ligands with high affinity to porcine TLR2, which is highly expressed in M cells and play an important role in mucosal immune responses in pigs, were identified through the cell-based phage display technique combined with high-throughput sequencing. A random phage-peptide library was applied to the porcine TLR2 overexpressing cell line and total 85, 557 unique peptide sequences were identified from approximately 9.0 × 107 reads after three rounds of both subtractive and non-subtractive biopanning via high-throughput sequencing. Among the unique sequences, three candidate peptide sequences, NAGHLSQ, VPSKPGL, and RANLDGQ, were selected based on their abundance in the third round of biopanning. Consequently, NAGHLSQ showed the highest affinity exclusively to porcine TLR2 compared with other candidates and its binding mechanism was inferred to be directly associated with ligand binding site of the TLR2 through the in vitro competitive analysis. The peptide identified in this research could be used in development of effective porcine mucosal vaccine as an M cell targeting moiety to enhance the transport of antigens into the Peyer's patch via oral route.

Abstract Background:Epidermal growth factor receptor (EGFR) activation may play an important role in blood spinal cord barrier (BSCB) disruption and secondary injury after SCI as it is significantly upregulated in the astrocytes (AS) and microvascular endothelial cells (MEC), which are the main component of cells in BSCB. EGFR inhibition alleviates the disruption of BSCB and improves the functional recovery in rats following spinal cord injury (SCI). However, the biological mechanisms underlying EGFR activation mediating secondary damage after SCI remain unclear. Methods:An in vitro model of Oxygen and glucose deprivation/reoxygenation (OGD/R) induced BSCB damage and in vivo rat SCI model was employed to define the role of EGFR activation and its induced inflammatory injury during this pathological process in AS and MEC. AS and MEC were exposed to EGFR or p38 MAPK up-regulation in the presence and absence of EGFR inhibitor, p38 MAPK inhibitor, NF-κB inhibitor, and/or appropriate shRNA. RT-PCR, ELISA and western blotting were used for mRNA and protein expression analyses of TNF-α, iNOS, COX-2 and IL-1β. Immunohistochemical staining and confocal microscopy were used to demonstrate cellular EGFR activation and to investigate the expression of tight junction (TJ) protein (ZO-1 and occludin). Measurement of transendothelial electrical resistance (TEER) and transendothelial FITC-dextran permeability were used to measure permeability of BSCB in vitro, while Evans blue dye extravasation test and evaluation spinal cord edema were used to detect permeability of BSCB in vivo.Results:The expression of pEGFR was significantly increased in BSCB component cells (AS and MEC) after SCI and BSCB damage model. EGFR activation induced inflammation injury by upregulating the expression of TNF-α, iNOS, COX-2, and IL-1β and BSCB disruption with loss of TJ protein by downregulating the expression of ZO-1 and occludin in BSCB damage model and SCI rats. Moreover, EGFR or p38 activation leads to NF-κB nuclear translocation in primary AS and MEC after OGD/R. The EGFR inhibitor as well as shRNA against EGFR markedly attenuated pro-inflammatory factor excessive producing and loss of TJ protein, and activation of the EGFR/p38/NF-κB pathway. While, EGFR overexpression significantly increased the expression of TNF-α, iNOS, COX-2, and IL-1β and decrease the expression of ZO-1 and occludin, inducing activation of the EGFR/p38/NF-κB pathway in both AS and MEC. Conclusion:This study strongly suggests that EGFR activation in BSCB component cells after SCI and BSCB damage model mediates both upregulation of pro-inflammation expression and downregulation of TJ protein downregulation via the EGFR/p38/NF-κB pathway. These findings contribute to a better understanding of the biological mechanisms underlying BSCB disruption and secondary injury following SCI mediating by EGFR activation.

Abstract Background Umbilical cord mesenchymal stem cells (HUCMSCs)-based therapies were previously predicated in cartilage regeneration due to the chondrogenic potential of MSCs. However, chondrogenic differentiation of HUMSCs is limited by administration of growth factors like TGF-β that may cause cartilage hypertrophy. It has been reported the exosomes could modulate phenotypic expression of stem cells. However, the role of human chondrogenic derived exosomes (C-EXO) in chondrogenic differentiation of HUCMSCs has not been reported. Results In this study, we successfully isolated chondrocyte-derived exosomes (C-EXO) from human multi-finger cartilage and found that C-EXO efficiently promoted the proliferation and chondrogenic differentiation of HUCMSCs, evidenced by highly expressed aggrecan (ACAN), COL2A and SOX-9. Also, the expression of the fibrotic marker, COL1A and hypertrophic marker, COL10, was significantly lower than that induced by TGF-β. In vivo, stimulation of C-EXO accelerated HUCMSCs-mediated cartilage repair in rabbit models. Furthermore, C-EXO led to increasing autophagosomes during the process of chondrogenic differentiation, indicating that C-EXO promoted cartilage regeneration might be through the activation of autophagy. Conclusions This study suggests that C-EXO has an essential role in fostering chondrogenic differentiation and proliferation of HUCMSCs, which may be a stable supply for articular cartilage repair.

Abstract BackgroundWidely used in recent years, mesenchymal stem cells (MSCs) expressing enhanced green fluorescent protein (eGFP) can be tracked during migration to injury sites, while also supporting tri-lineage differentiation. However, the relationship between the expression of green fluorescence and the magnitude of osteogenic differentiation is not clearly defined. Despite increasing use of eGFP-MSCs derived from the transgenic pigs and non-viral eGFP plasmid transfected MSCs in recent years, it remains unclear which cells are suitable for tracking during osteogenic differentiation, and whether the transfected plasmid alters osteogenic potential.MethodsWe compared the expression of green fluorescence and the magnitude of osteogenic differentiation between eGFP MSCs from a transgenic pig (group 1) and non-virally transfected eGFP-MSCs using transIT®-2020 (group 2). Non-transfected MSCs were used as control group (group 3). We also use a scaffold to compare the osteogenic induction environments created by 2-D monolayer cultures and 3-D cultures, respectivelyResultsIn the monolayer culture, flow cytometry from day 7 to day 28 showed that the percentage of green fluorescent cells in groups 1 and 2 were 99.6% and 59.7% of total cell counts, respectively. Quantification showed that eGFP expression peaked on day 7, decreased after day 14, and plateaued to day 28 in group 1 and group 2. Significant aggregation of eGFP over bone-like nodules was appreciated in group 1. In 3-D culture, eGFP expression increased from day 7 to day 28 in both groups, and was higher in group 1 than in group 2 at each time point. Osteogenic profiles and immunohistochemistry showed more significant osteogenic activity in group 1 and group 3 than in group 2. ConclusionsThe expression of eGFP in the test groups did not significantly change after osteogenic induction. However, quantification data was different in monolayer and 3-D cultures due to spatial limitations, differing extracellular environments, and heterogeneous cell morphology and methods of division. Osteogenic profiles and immunohistochemistry data confirmed that osteogenic potential did not change in transgenic pig-derived MSCs. However osteogenic potential decreased in pig MSCs (pig MSCs) treated with the transfection reagent, likely from related toxicity.

Abstract Background Antimicrobial photodynamic therapy (APDT) is a promising alternative to traditional antibiotics for bacterial infections, which inactivates a broad spectrum of bacteria. However, it has some disadvantages including poor water solubility and easy aggregation of hydrophobic photosensitizers (PS), and poor tissue penetration and cytotoxicity when using UV as the light source, leading to undesired photodynamic therapy efficacy.Results In this study, we develop a novel water-soluble natural PS (sorbicillinoids) obtained by microbial fermentation using recombinant filamentous fungus Trichoderma reesei (T. reesei). Sorbicillinoids could effectively generate singlet oxygen (1O2) under ultraviolet (UV) light irradiation, and ultimately display photoinactivation activity on Gram-positive bacteria, but not Gram-negative ones. Staphylococcus aureus (S. aureus) treated with sorbicillinoids and UV light displayed high levels of intracellular reactive oxygen species (ROS), notable DNA photocleavage, and compromised cell semi-permeability without overt cell membrane disruption. Moreover, the dark toxicity, phototoxicity or hemolysis activity of sorbicillinoids is negligible, showing its excellent biocompatibility.Conclusion Sorbicillinoids obtained from T. reesei display photoinactivation activity on Gram-positive bacteria using nontoxic dose of UV light irradiation and have an excellent biocompatibility Therefore, sorbicillinoids, a type of secondary metabolite from fungus, has a promising future as a new PS for APDT.

Abstract Background: Resisting cell death is one of the hallmarks of cancer. Necroptosis is a form of non-caspase dependent necrotic cell death mediated by receptor-interacting protein kinase-1/3 (RIP1/3), which represents another mode of programmed cell death besides apoptosis. Growing evidence supports that RIP3 has emerged as a critical regulator of necroptosis and can be activated by several stimuli to trigger necroptotic cell death in a RIP1-independent manner. RIP3 also acts as an energy metabolism regulator associated with switching cell death from apoptosis to necroptosis. Natural products provide a unique source for the discovery of innovative leading compounds and drugs, which exhibits promising anticancer activities through inducing cell death and enhancing chemotherapeutic sensitivity. Trichothecin (TCN) is a sesquiterpenoid originating from an endophytic fungus of the herbal plant Maytenus hookeri Loes and shows potent anti-tumor bioactivity. However, the underlying mechanism is not fully understood.Methods: Cell permeability assay and transmission electron microscopy were applied to identify the death pattern induced by TCN in apoptotic-resistant cancer cells. We used Seahorse extracellular flux analyzer to examine the cellular oxygen consumption rate (OCR) and flow cytometry to detect mitochondrial reactive oxygen species (ROS) content. Xenograft animal experiment was performed to assess the effect of TCN synergized with cisplatin to enhance chemotherapeutic sensitivity of tumor cells. Results: Our current findings revealed that RIP3 mediated TCN-induced necroptosis through activating mitochondria energy metabolism and ROS production in apoptotic-resistant cancer cells. RIP3 might be involved in sensitizing tumor cells to chemotherapy induced by TCN. Conclusions: Activating RIP3 to induce necroptosis through reprogramming mitochondrial energy metabolism and ROS production contributes to the anti-tumor activity of TCN. Moreover, TCN could be exploited for therapeutic gain through up-regulating RIP3 to sensitize cancer chemotherapy.

Abstract Despite continuous active development of fluorescent probes for metal-ions, their molecular design for ratiometric detection is limited owing to a narrow choice of available sensing mechanisms. We present herein a dual-emission sensing platform for metal ions based on contact interaction between a coordinated metal ion and the aromatic ring of a fluorophore (i.e., arene–metal-ion contact). Our structure-based ligand design provided a new probe possessing BPTN as the metal ion binding unit, which was flexibly concatenated to a tricyclic fluorophore. This molecular architecture allowed us to fluorescently sense various metal ions such as Zn(II), Cu(II), Cd(II), Ag(I), and Hg(II) with the red-shifted emissions. This probe design was applicable to a series of tricyclic fluorophores, enabling ratiometric detection of the metal ions across the blue to near-infrared wavelength region. X-ray crystallography and theoretical computational calculation indicated that the coordinated metal ion has van der Waals contact with the fluorophore, which perturbs its electronic structure and ring conformation to induce the emission red-shift. A set of the arene–metal-ion contact probes was used for the differential sensing of eight metal ions in a one-pot single titration via PCA analysis. Furthermore, the probe was applicable to the ratio imaging of metal ions under live-cell conditions.

Abstract Background. Injuries to the peripheral nerve system are common conditions, with broad spectrum of symptoms depending on the impaired nerves and severity of damage. Although peripheral nervous system retains a remarkable ability for regeneration, it is estimated that less than ten percent of patients fully recover function after nerve injury and the available treatments remain suboptimal. Here, we identify a role for the obestatin/GPR39 system in the regulation of the Schwann cell plasticity as well as in the preservation of neuromuscular synapses in the course of nerve repair. Methods. Utilizing a compression model of sciatic nerve injury, axonotmesis, we assessed the obestatin-related regenerative response in the peripheral nerve system. The role of the obestatin/GPR39 system was further evaluated on immortalized rat Schwann cells, IFRS1, and the model of neuronal differentiation, PC12 cells. The interactions between SCs and neurons was evaluated using a co-culture system that combine the SC cell line IFRS1 and the NGF-primed PC12. Results. Obestatin signaling directs proliferation and migration of Schwann cells that sustain axonal regrowth and later remyelinate regenerated axons. We provide evidence supporting the preservation of skeletal muscle by the maintenance of neuromuscular synapses through the axonal regulation of calpain-calpastatin proteolytic system. This encompasses the control of skeletal muscle homeostasis by regulation of the ubiquitin proteasome system and the autophagy machinery. Conclusions. These results provide important insights into how the obestatin/GPR39 system promotes nerve repair through integration of multiple molecular cues of neuron-Schwann cells crosstalk aimed to promote axon growth and guide axons back to their targets.

MicroRNAs modulate a variety of cellular events, including skeletal muscle development, but the molecular basis of their functions in fetal bovine skeletal muscle development is poorly understood. In this study, we report that bta-miR-24-3p promotes the myogenic differentiation of fetal bovine PDGFRα- progenitor cells. The expression of bta-miR-24-3p increased during myogenic differentiation. Overexpression of bta-miR-24-3p significantly promoted myogenic differentiation, but inhibited proliferation. A dual-luciferase assay identified ACVR1B as a direct target of bta-miR-24-3p. Similarly, knocking down ACVR1B by RNA interference also significantly inhibited proliferation and promoted the differentiation of bovine PDGFRα- progenitor cells. Thus, our study provides a mechanism in which bta-miR-24-3p regulates myogenesis by inhibiting ACVR1B expression.

The infection of Enterococcus faecalis and its interacting microorganisms in the root canal could cause persistent apical periodontitis (AP). Antibacterial root canal sealer has favorable prospects to inhibit biofilms. The purpose of this study was to investigated the antibacterial effect of root canal sealer containing dimethylaminododecyl methacrylate (DMADDM) on persistent AP in beagle dogs for the first time. Persistent AP was established by a two-step infection with Enterococcus faecalis and multi-bacteria (Enterococcus faecalis, Lactobacillus acidophilus, Actinomycesnaeslundii, Streptococcus gordonii). Root canal sealer containing DMADDM (0%, 1.25%, 2.5%) was used to complete root canal filling. The volume of lesions and inflammatory grade in the apical area were evaluated by cone beam computer tomography (CBCT) and hematoxylin-eosin staining. Both Enterococcus-faecalis- and multi-bacteria-induced persistent AP caused severe apical destruction, and there were no significant differences in pathogenicity between them. DMADDM-modified sealer significantly reduced the volume of periapical lesion and inflammatory grade compared with the control group, among them, the therapeutic effect of the 2.5% group was better than the 1.25% group. In addition, E.faecalis-induced reinfection was more sensitive to the 2.5% group than multi-bacteria reinfection. This study shows that root canal sealer containing DMADDM had a remarkable therapeutic effect on persistent AP, especially on E. faecalis-induced reinfection.

Existing therapies for Parkinson’s disease (PD) are only symptomatic. As erythropoietin (EPO) is emerging for its benefits in neurodegenerative diseases, here, we test the protective effect driven by EPO in in vitro (SH-SY5Y cells challenged by MPP+) and in vivo (C57BL/6J mice administered with MPTP) PD models. EPO restores cell viability in both protective and restorative layouts, enhancing the dopaminergic recovery. Specifically, EPO rescues the PD-induced damage to mitochondria, as shown by transmission electron microscopy, Mitotracker assay and PINK1 expression. Moreover, EPO promotes a rescue of mitochondrial respiration while markedly enhancing the glycolytic rate, as shown by the augmented extracellular acidification rate, contributing to elevated ATP levels in MPP+-challenged cells. In PD mice, EPO intrastriatal infusion markedly improves the outcome of behavioral tests. This is associated with the rescue of dopaminergic markers and decreased neuroinflammation. This study demonstrates cellular and functional recovery following EPO treatment, likely mediated by the 37 Kda isoform of the EPO-receptor. We report for the first time, that EPO-neuroprotection is exerted through restoring ATP levels by accelerating the glycolytic rate. In conclusion, the redox imbalance and neuroinflammation associated with PD may be successfully treated by EPO.

Abstract Background The Mediator complex transduces information from the DNA-bound transcription factors to the RNA polymerase II transcriptional machinery. Research on plant Mediator subunits was mainly performed in Arabidopsis, while very few of them have been functionally characterized in rice. Results Here the rice Mediator subunit 16, OsMed16, was studied. OsMed16 encoded a putative protein of 1301 amino acids, which is longer than the reported version. It was expressed in various rice organs, and localized in nucleus. Knockout of OsMed16 caused rice seedling lethality. Its overexpression led to rice growth retardation, low yield, and spontaneous cell death in leaf blade and leaf sheath. RNA sequencing suggested that overexpression of OsMed16 altered the expression of a large number of genes. Among them, the up-regulation of some defense-related genes was verified. Conclusions Our results demonstrated that OsMed16 can regulate the expression of a wealth of genes, and alterations in its expression have profound impact on plant growth, development and defense response in rice.

Maltol, a food-flavoring agent and Maillard reaction product formed during the processing of red ginseng (Panax ginseng, C.A. Meyer), has been confirmed to exert a hepatoprotective effect in alcohol-induced oxidative damage in mice. However, its beneficial effects on acetaminophen (APAP)-induced hepatotoxicity and the related molecular mechanisms remain unclear. The purpose of this article was to investigate the protective effect and elucidate the mechanisms of action of maltol on APAP-induced liver injury in vivo. Maltol was administered orally at 50 and 100 mg/kg daily for seven consecutive days, then a single intraperitoneal injection of APAP (250 mg/kg) was performed after the final maltol administration. Liver function, oxidative indices, inflammatory factors—including serum alanine and aspartate aminotransferases (ALT and AST), tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), liver glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA), cytochrome P450 E1 (CYP2E1) and 4-hydroxynonenal (4-HNE) were measured. Results demonstrated that maltol possessed a protective effect on APAP-induced liver injury. Liver histological changes and Hoechst 33258 staining also provided strong evidence for the protective effect of maltol. Furthermore, a maltol supplement mitigated APAP-induced inflammatory responses by increasing phosphorylated nuclear factor-kappa B (NF-κB), inhibitor kappa B kinase α/β (IKKα/β), and NF-kappa-B inhibitor alpha (IκBα) in NF-κB signal pathways. Immunoblotting results showed that maltol pretreatment downregulated the protein expression levels of the B-cell-lymphoma-2 (Bcl-2) family and caspase and altered the phosphorylation of phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) in a dose-dependent manner. In conclusion, our findings clearly demonstrate that maltol exerts a significant liver protection effect, which may partly be ascribed to its anti-inflammatory and anti-apoptotic action via regulation of the PI3K/Akt signaling pathway.

Estrogen (E2) is a major risk factor for the initiation and progression of malignancy in estrogen receptor (ER) positive breast cancers, whereas sirtuin 3 (Sirt3), a major mitochondrial NAD+-dependent deacetylase, has the inhibitory effect on the tumorigenic properties of ER positive MCF-7 breast cancer cells. Since it is unclear if this effect is mediated through the estrogen receptor alpha (ERα) signaling pathway, in this study, we aimed to determine if the tumor-suppressive function of Sirt3 in MCF-7 cells interferes with their response to E2. Although we found that Sirt3 improves the antioxidative response and mitochondrial fitness of the MCF-7 cells, it also increases DNA damage along with p53, AIF, and ERα expression. Moreover, Sirt3 desensitizes cells to the proliferative effect of E2, affects p53 by disruption of the ERα–p53 interaction, and decreases proliferation, colony formation, and migration of the cells. Our observations indicate that these tumor-suppressive effects of Sirt3 could be reversed by E2 treatment only to a limited extent which is not sufficient to recover the tumorigenic properties of the MCF-7 cells. This study provides new and interesting insights with respect to the functional role of Sirt3 in the E2-dependent breast cancers.

The three-dimensional complexity of the native extracellular matrix (ECM) suggests switching from 2D to 3D culture systems for providing the cells with an architecture more similar to the physiological environment. Reproducing the three-dimensionality in vitro can guarantee beneficial effects in terms of cell growth, adhesion, proliferation, and/or their differentiation. Hydrogels have the same tailorable physico-chemical and biological characteristics as ECM materials. In this study, we propose a thermoresponsive chitosan-based hydrogel that gels thanks to the addition of organic and inorganic salt solutions (beta-glycerolphosphate and sodium hydrogen carbonate) and is suitable for cell encapsulation allowing obtaining 3D culture systems. Physico-chemical analyses showed that the hydrogel formulations jellify at physiological conditions (37 °C, pH 7.4), are stable in vitro up to three weeks, have high swelling ratios and mechanical stiffness suitable for cellular encapsulation. Moreover, preliminary biological tests underlined the pronounced biocompatibility of the system. Therefore, these chitosan-based hydrogels are proposed as valid biomaterials for cell encapsulation.

Light profoundly affects the circadian clock and the activity levels of animals. Along with the systematic changes in intensity and spectral composition, over the 24-h day, light shows considerable irregular fluctuations (noise). Using light as the Zeitgeber for the circadian clock is, therefore, a complex task and this might explain why animals utilize multiple photoreceptors to entrain their circadian clock. The fruit fly Drosophila melanogaster possesses light-sensitive Cryptochrome and seven Rhodopsins that all contribute to light detection. We review the role of Rhodopsins in circadian entrainment, and of direct light-effects on the activity, with a special emphasis on the newly discovered Rhodopsin 7 (Rh7). We present evidence that Rhodopsin 6 in receptor cells 8 of the compound eyes, as well as in the extra retinal Hofbauer-Buchner eyelets, plays a major role in entraining the fly’s circadian clock with an appropriate phase-to-light–dark cycles. We discuss recent contradictory findings regarding Rhodopsin 7 and report original data that support its role in the compound eyes and in the brain. While Rhodopsin 7 in the brain appears to have a minor role in entrainment, in the compound eyes it seems crucial for fine-tuning light sensitivity to prevent overshooting responses to bright light.

Melampsora larici-populina (Mlp), the causal agent of Populus leaf rust, secretes an array of effectors into the host through the haustorium to gain nutrients and suppress immunity. The precise mechanisms by which these effectors promote virulence remain unclear. To address this question, we developed a transgenic Arabidopsis line expressing a candidate effector, Mlp124357. Constitutive expression of the effector increased plant susceptibility to pathogens. A GxxxG motif present in Mlp124357 is required for its subcellular localization at the vacuolar membrane of the plant cell, as replacement of the glycine residues with alanines led to the delocalization of Mlp124357 to the nucleus and cytoplasm. We used immunoprecipitation and mass spectrometry (MS) to identify Mlp124357 interaction partners. Only one of the putative interaction partners knock-out line caused delocalization of the effector, indicating that Arabidopsis protein disulfide isomerase-11 (AtPDI-11) is required for the effector localization. This interaction was further confirmed by a complementation test, a yeast-two hybrid assay and a molecular modeling experiment. Moreover, localization results and infection assays suggest that AtPDI-11 act as a helper for Mlp124357. In summary, our findings established that one of Mlp effectors resides at the vacuole surface and modulates plant susceptibility.