Solution structure of plant nonspecific lipid transfer protein-2 from rice (Oryza sativa)

The three-dimensional structure of rice nonspecific lipid transfer protein (nsLTP2) has been solved for the first time. The structure of nsLTP2 was obtained using 813 distance constraints, 30 hydrogen bond constraints, and 19 dihedral angle constraints. Fifteen of the 50 random simulated annealing structures satisfied all of the constraints and possessed good nonbonded contacts. The novel three-dimensional fold of rice nsLTP2 contains a triangular hydrophobic cavity formed by three prominent helices. The four disulfide bonds required for stabilization of the nsLTP2 structure show a different pattern of cysteine pairing compared with nsLTP1. The C terminus of the protein is very flexible and forms a cap over the hydrophobic cavity. Molecular modeling studies suggested that the hydrophobic cavity could accommodate large molecules with rigid structures, such as sterols. The positively charged residues on the molecular surface of nsLTP2 are structurally similar to other plant defense proteins.     

Hydrogen Evolution and Absorption Phenomena in the Plasma Membrane of Vigna radiata and Capsicum annuum

Journal of Plant Growth Regulation - Molecular hydrogen has been shown to exert beneficial effects on plant growth and abiotic stress tolerance, however, the exact mechanism has not yet been fully...     

The pro‐inflammatory response of macrophages regulated by acid degradation products of poly(lactide‐co‐glycolide) nanoparticles

Poly(lactide‐co‐glycolide) (PLGA) shows great potentials in biomedical applications, in particular with the field of biodegradable implants and control release technologies. However, there are few systematic and detailed studies on the influence of PLGA degradation behavior on the immunogenicity. In this study, in order to develop a method for dynamically assessing the immunological response of PLGA throughout the implantation process, PLGA particles are fabricated using an o/w single‐emulsion method. The physicochemical characterizations of the prepared PLGA particles during in vitro hydrolytic degradation are investigated. Then, a series of immunological effects triggered by PLGA by‐products formed with degradation process are evaluated, including cell viability, apoptosis, polarization and inflammatory reaction. THP‐1 human cell line is set as in vitro cell model. Our results show that PLGA degradation‐induced acid environment decreases cell viability and increases cell apoptosis, which is a potential factor affecting cell function. In particular, the macrophages exhibit up‐regulations in both M1 subtype related surface markers and pro‐inflammatory cytokines with the degradation process of PLGA, which indicates the degradation products of PLGA can convert macrophages to the pro‐inflammatory (M1) polarization state. All these findings provide the mechanism of PLGA‐induced inflammation and lay the foundation for the design of next‐generation PLGA‐based biomaterials endowed with immunomodulatory functions.     

Wnt signaling enhances FGF2-triggered lens fiber cell differentiation

Wnt signaling is implicated in many developmental processes, including cell fate changes. Several members of the Wnt family, as well as other molecules involved in Wnt signaling, including Frizzled receptors, LDL-related protein co-receptors, members of the Dishevelled and Dickkopf families, are known to be expressed in the lens during embryonic or postembryonic development. However, the function of Wnt signaling in lens fiber differentiation remains unknown. Here, we show that GSK-3beta kinase is inactivated and that beta-catenin accumulates during the early stages of lens fiber cell differentiation. In an explant culture system, Wnt conditioned medium (CM) induced the accumulation of beta-crystallin, a marker of fiber cell differentiation, without changing cell shape. In contrast, epithelial cells stimulated with Wnt after priming with FGF elongated, accumulated beta-crystallin, aquaporin-0, p57kip2, and altered their expression of cadherins. Treatment with lithium, which stabilizes beta-catenin, induced the accumulation of beta-crystallin, but explants treated with lithium after FGF priming did not elongate as they did after Wnt application. These results show that Wnts promote the morphological aspects of fiber cell differentiation in a process that requires FGF signaling, but is independent of beta-catenin. Wnt signaling may play an important role in lens epithelial-to-fiber differentiation.     

Granulysin, a cytolytic molecule, is also a chemoattractant and proinflammatory activator

Granulysin, a cationic protein produced by activated human CTL and NK cells, is cytolytic against microbial and tumor targets. In this study we show that granulysin also functions as a chemoattractant and activates monocytes to produce cytokines/chemokines. Although granulysin-mediated cytotoxicity occurs at micromolar concentrations, chemoattraction occurs in the nanomolar range, and immune activation occurs over a wide range of concentrations (nanomolar to micromolar). Granulysin causes a 2- to 7-fold increase in chemotaxis of monocytes, CD4(+), and CD8(+) memory (CD45RO) but not naive (CD45RA) T cells, NK cells, and mature, but not immature, monocyte-derived dendritic cells. Pertussis toxin treatment abrogates chemoattraction by granulysin, indicating involvement of G-protein-coupled receptor(s). At low concentrations (10 nM), granulysin promotes a 3- to 10-fold increase in MCP-1 and RANTES produced by monocytes and U937 cells, while a 2-fold increase in TNF-alpha production by LPS-stimulated monocytes requires higher concentrations of granulysin (micromolar). Taken together, these data indicate that the local concentration of granulysin is critical for the biologic activity, with high concentrations resulting in cytotoxicity while lower concentrations, presumably further from the site of granulysin release, actively recruit immune cells to sites of inflammation.     

Modulation of oxidative phosphorylation augments antineoplastic activity of mitotic aurora kinase inhibition

Uncontrolled mitosis is one of the most important features of cancer, and mitotic kinases are thought to be ideal targets for anticancer therapeutics. However, despite numerous clinical attempts spanning decades, clinical trials for mitotic kinase-targeting agents have generally stalled in the late stages due to limited therapeutic effectiveness. Alisertib (MLN8237) is a promising oral mitotic aurora kinase A (AURKA, Aurora-A) selective inhibitor, which is currently under several clinical evaluations but has failed in its first Phase III trial due to inadequate efficacy. In this study, we performed genome-wide CRISPR/Cas9-based screening to identify vulnerable biological processes associated with alisertib in breast cancer MDA-MB-231 cells. The result indicated that alisertib treated cancer cells are more sensitive to the genetic perturbation of oxidative phosphorylation (OXPHOS). Mechanistic investigation indicated that alisertib treatment, as well as other mitotic kinase inhibitors, rapidly reduces the intracellular ATP level to generate a status that is highly addictive to OXPHOS. Furthermore, the combinational inhibition of mitotic kinase and OXPHOS by alisertib, and metformin respectively, generates severe energy exhaustion in mitotic cells that consequently triggers cell death. The combination regimen also enhanced tumor regression significantly in vivo. This suggests that targeting OXPHOS by metformin is a potential strategy for promoting the therapeutic effects of mitotic kinase inhibitors through the joint targeting of mitosis and cellular energy homeostasis.Subject terms: Mitosis, Cancer screening, Preclinical research     

Different Visual Preference Patterns in Response to Simple and Complex Dynamic Social Stimuli in Preschool-Aged Children with Autism Spectrum Disorders

Eye-tracking studies in young children with autism spectrum disorder (ASD) have shown a visual attention preference for geometric patterns when viewing paired dynamic social images (DSIs) and dynamic geometric images (DGIs). In the present study, eye-tracking of two different paired presentations of DSIs and DGIs was monitored in a group of 13 children aged 4 to 6 years with ASD and 20 chronologically age-matched typically developing children (TDC). The results indicated that compared with the control group, children with ASD attended significantly less to DSIs showing two or more children playing than to similar DSIs showing a single child. Visual attention preference in 4- to 6-year-old children with ASDs, therefore, appears to be modulated by the type of visual stimuli.     

Eight-Shaped Hatching Increases the Risk of Inner Cell Mass Splitting in Extended Mouse Embryo Culture

Increased risk of monozygotic twinning (MZT) has been shown to be associated with assisted reproduction techniques, particularly blastocyst culture. Interestingly, inner cell mass (ICM) splitting in human ‘8’-shaped hatching blastocysts that resulted in MZT was reported. However, the underlying cause of MZT is not known. In this study, we investigated in a mouse model whether in vitro culture leads to ICM splitting and its association with hatching types. Blastocyst hatching was observed in: (i) in vivo developed blastocysts and (ii–iii) in vitro cultured blastocysts following in vivo or in vitro fertilization. We found that ‘8’-shaped hatching occurred with significantly higher frequency in the two groups of in vitro cultured blastocysts than in the group of in vivo developed blastocysts (24.4% and 20.4% versus 0.8%, respectively; n = 805, P < 0.01). Moreover, Oct4 immunofluorescence staining was performed to identify the ICM in the hatching and hatched blastocysts. Scattered and split distribution of ICM cells was observed around the small zona opening of ‘8’-shaped hatching blastocysts. This occurred at a high frequency in the in vitro cultured groups. Furthermore, we found more double OCT4-positive masses, suggestive of increased ICM splitting in ‘8’-shaped hatching and hatched blastocysts than in ‘U’-shaped hatching and hatched blastocysts (12.5% versus 1.9%, respectively; n = 838, P < 0.01). Therefore, our results demonstrate that extended in vitro culture can cause high frequencies of ‘8’-shaped hatching, and ‘8’-shaped hatching that may disturb ICM herniation leading to increased risk of ICM splitting in mouse blastocysts. These results may provide insights into the increased risk of human MZT after in vitro fertilization and blastocyst transfer.