Patterned Hybrid Wettability Surfaces for Fog Harvesting.

The scarcity of fresh water resources has become increasingly serious in recent years, posing threats to the survival of mankind. The ability of the animals and plants in arid areas to collect water from moisture and fog has drawn attention worldwide. Inspired by the synergistic fog harvesting mode of natural organisms with superhydrophilic and superhydrophobic patterning, a composite membrane with a concave-convex morphology and hybrid wettability was prepared aiming at efficient fog harvesting. The hybrid wettability surface was obtained by chemically modifying the superhydrophilic PAN substrate with 1H,1H,2H,2H-perfluorooctyltrichlorosilane using iron mesh as the mask. The porous PAN substrate was prepared by the non-solvent-induced phase separation (NIPS) method. Fog harvesting is a three-step process: condensation, coalescence, and rapid transportation of water droplets. The area and ratio of the hydrophilic/hydrophobic regions were tuned by adjusting the mesh number of the iron meshes. Under the optimal condition, the fog harvesting efficiencies of 40.3 and 74.2 mg·cm-2·min-1 were obtained when the fog yields were 0.05 and 0.1 L·min-1, respectively. The present work provides an alternative strategy for addressing the shortage of fresh water resources.

Construction of Specific and Reversible Nanoreceptors for Proteins via Sequential Surface-Imprinting Strategy.

Molecular recognition of proteins is critical for study and manipulation of protein-related biological processes. However, design and synthesis of abiotic receptors for precise recognition of proteins still remains a challenging task. Herein, we developed a universal sequential surface-imprinting strategy that integrated two different types of imprinting reactions to construct artificial protein receptors with high selectivity. Employing dopamine self-polymerization and boronate/diol complexation as the first-step and second-step imprinting reactions, respectively, we synthesized surface-imprinted magnetic nanocomposites against two different enzyme proteins: deoxyribonuclease I (DNase I) and apurinic/apyrimidinic endonuclease/redox effector factor 1 (APE1). The obtained nanocomposites both showed strong and specific binding toward their respective template proteins. Moreover, the bound enzymes could be totally recovered with high activity under mild buffer conditions. These antibody-like specific and reversible binding properties enabled effective purification and enrichment of the low-abundance target proteins from complex serum samples. Compared to existing one-pot or one-step imprinting methods, the proposed sequential surface-imprinting approach offers a more flexible combination of different functional monomers and greatly enhances the performance and biocompatibility of the imprinted materials. The generality and simplicity of the sequential imprinting strategy would make it an appealing and competitive method to prepare artificial protein receptors.

Metal-Ion-Responsive Bionanocomposite for Selective and Reversible Enzyme Inhibition.

A bionanocomposite with artificial binding pockets for a DNA repair enzyme has been developed by in situ assembly of an affinity protein with a surrounding contact surface of polydopamine on the surface of silica coated magnetic nanoparticles via molecular imprinting reactions. The obtained nanoparticles exhibited antibody-like binding behavior toward the target enzyme with highly specific and efficient inhibition effect. Moreover, the binding and inhibition could be flexibly tuned by the addition of metal ions such as Mn2+ and Mg2+, which provided a convenient tool to regulate enzyme activity with artificially engineered nanoinhibitors.

Analysis of the roles of MAD proteins in the wing dimorphism of Nilaparvata lugens.

Wing dimorphism in Nilaparvata lugens is controlled by the insulin-like growth factor 1 (IGF-1) signaling - Forkhead transcription factors (IIS-FoxO) pathway. However, the role of this signal in the wing development program remains largely unclear. Here, we identified 2 R-SMAD proteins, NlMAD1 and NlMAD2, in the brown planthopper (BPH) transcriptome, derived from the intrinsic transforming growth factor-ß pathway of insect wing development. Both proteins share high sequence similarity and conserved domains. Phylogenetic analysis placed them in the R-SMAD group and revealed related insect orthologs. The expression of Nlmad1 was elevated in the late instar stages of the macropterous BPH strain. Nlmad1 knockdown in nymphs results in malformed wings and reduced wing size in adults, which affects the forewing membrane. By contrast, Nlmad2 expression was relatively consistent across BPH strains and different developmental stages. Nlmad2 knockdown had a milder effect on wing morphology and mainly affected forewing veins and cuticle thickness in the brachypterous strain. NlMAD1 functions downstream of the IIS-FoxO pathway by mediating the FoxO-regulated vestigial transcription and wing morph switching. Inhibiting Nlmad1 partially reversed the long-winged phenotype caused by NlFoxO knockdown. These findings indicate that NlMAD1 and NlMAD2 play distinct roles in regulating wing development and morph differentiation in BPH. Generally, NlMAD1 is a key mediator of the IIS-FoxO pathway in wing morph switching.

Effects of Elevated CO2 on the Fitness of Three Successive Generations of Lipaphis erysimi.

To assess the effect of elevated CO2 on the development, fecundity, and population dynamic parameters of L. erysimi, the age-stage, two-sex life table was used to predict the individual fitness and population parameters of three successive generations of L. erysimi in this study. The results show that a significantly longer total pre-adult stage before oviposition (TPOP) was observed in the third generation compared with the first generation of L. erysimi under the 800 µL/L CO2 treatment. The fecundity is significantly lower in the 800 µL/L CO2 treatment than that in the 400 µL/L CO2 treatment in the third generation of L. erysimi, which indicates that elevated CO2 had a negative effect on the individual fitness parameters of L. erysimi. Additionally, the life expectancy (exj) is significantly lower under the 800 µL/L CO2 treatment than that under the 400 µL/L CO2 treatment in the three successive generations. A significantly higher intrinsic rate of increase (r) and finite rate of increase (λ) were found in the second generation compared with those in the first and third generations of L. erysimi under the 800 µL/L CO2 treatment. Moreover, significantly lower r and λ were observed under the 800 µL/L CO2 treatment compared with those under the 400 µL/L and 600 µL/L CO2 treatments in the first generation of L. erysimi, which indicates that elevated CO2 has a short-term effect on the population parameters (r and λ) of L. erysimi. Our experiment can provide the data for the comprehensive prevention and control of L. erysimi in the future with increasing CO2 levels.

An InR/mir-9a/NlUbx regulatory cascade regulates wing diphenism in brown planthoppers.

Wing polymorphism significantly contributes to the ecological success of some insect species. For example, the brown planthopper (BPH) Nilaparvata lugens, which is one of the most destructive rice pests in Asia, can develop into either highly mobile long-winged or highly fecund short-winged adult morphs. A recent study reported a highly provocative result that the Hox gene Ultrabithorax (Ubx) is expressed in BPH forewings and showed that this wing development gene is differentially expressed in nymphs that develop into long-winged versus short-winged morphs. Here, we found that Ubx may be a mir-9a target, and used dual luciferase reporter assays and injected micro RNA (miRNA) mimics and inhibitors to confirm the interactions between mir-9a and NlUbx. We measured the mir-9a and NlUbx expression profiles in nymphs and found that the expression of these two biomolecules was negatively correlated. By rearing BPH nymphs on host rice plants with different nutritional status, we were able to characterize a regulatory cascade between insulin receptor genes, mir-9a, and NlUbx that regulate wing length in BPHs. When host quality was low, NlInR1 expression in the nymph terga increased and NlInR2 expression decreased; this led to a higher mir-9a level, which in turn reduced the NlUbx transcript level and ultimately resulted in longer wing lengths. Beyond extending our understanding of the interplay between host plant status and genetic events that modulate polymorphism, we demonstrated both the upstream signal and miRNA-based regulatory mechanism that control Ubx expression in BPH forewings.

Time-dependent stress evidence in dynamic allocation of physiological metabolism of Nilaparvata lugens in response to elevated CO2.

To assess the time-dependent stress evidence in dynamic allocation of physiological metabolism of Nilaparvata lugens nymphs in response to elevated CO2, we measured the time-dependent allocation of nutrient compositions and physiological metabolism in the bodies of N. lugens at 1h, 4h and 12h under elevated CO2. Elevated CO2 significantly increased the contents of nutrient compositions (protein, glucose and total amino acids) and catalase (CAT) enzyme activity in the body of N. lugens at 12h relative to 1h and 4h (P < 0.05). Significantly higher genes expression levels of acetylcholinesterase (AChE), heat shock protein (HSP70) and vitellogenin gene (vg) were observed in the body of N. lugens compared with those in ambient CO2 at 4h (P < 0.05). These results showed that there was an instantaneous reaction of N. lugens nymphs to elevated CO2, which indicated N. lugens may enhance stress defense response to future increasing CO2 levels.

Ultrabithorax is a key regulator for the dimorphism of wings, a main cause for the outbreak of planthoppers in rice.

Rice planthoppers, the most devastating rice pests, occur in two wing forms: the short-wing form for rapid population growth and long-wing form for long-distance migration, which together create the mechanism for outbreak. Here we show that Ultrabithorax (Ubx) is a key regulator for switching between the long- and short-wing forms of rice planthoppers. Ubx is expressed in both forewing and hindwing pads, which is different from the canonical model of Ubx expression. In brown planthoppers, expression of Ubx (NlUbx) is regulated by nutritional status of the rice host. High-quality young plants induce NlUbx expression leading to the short-wing form; low-quality ripe plants reduce NlUbx expression resulting in long-wing form. We also showed that NlUbx is regulated by the insulin receptors NlInR1 and NlInR2. The default expression of NlInR1 inhibits NlUbx resulting in long-wings, while high-quality hosts induce NlInR2 expression, which represses NlInR1 thus promoting NlUbx expression to produce short-wings.