Coassembly of Tobacco Mosaic Virus Coat Proteins into Nanotubes with Uniform Length and Improved Physical Stability

Using tobacco mosaic virus coat proteins (TMVcp) from both sources of the plant and bacterial expression systems as building blocks, we demonstrate here a coassembly strategy of TMV nanotubes in the presence of RNA. Specifically, plant-expressed cp (cp_p) efficiently dominates the genomic RNA encapsidation to determine the length of assembled TMV nanotubes, whereas the incorporated <i>Escherichia coli-</i>expressed cp (cp_ec) improves the physical stability of TMV nanotubes by introducing disulfide bonds between the interfaces of subunits. We expect this coassembly strategy can be expanded to other virus nanomaterials to obtain desired properties based on rationally designed protein–RNA and protein–protein interfacial interactions

Selective in Situ Assembly of Viral Protein onto DNA Origami

Engineering hybrid protein–DNA assemblies in a controlled manner has attracted particular attention, for their potential applications in biomedicine and nanotechnology due to their intricate folding properties and important physiological roles. Although DNA origami has served as a powerful platform for spatially arranging functional molecules, <i>in situ</i> assembly of proteins onto DNA origami is still challenging, especially in a precisely controlled and facile manner. Here, we demonstrate <i>in situ</i> assembly of tobacco mosaic virus (TMV) coat proteins onto DNA origami to generate programmable assembly of hybrid DNA origami–protein nanoarchitectures. The protein nanotubes of controlled length are precisely anchored on the DNA origami at selected locations using TMV genome-mimicking RNA strands. This study opens a new route to the organization of protein and DNA into sophisticated protein–DNA nanoarchitectures by harnessing the viral encapsidation mechanism and the programmability of DNA origami

Self-Assembly of Protein Crystals with Different Crystal Structures Using Tobacco Mosaic Virus Coat Protein as a Building Block

In this work, a typical cylinder-shaped tobacco mosaic virus coat protein (TMVCP) is employed as an anisotropic building block to assemble into triclinic and hexagonal close-packed (HCP) protein crystals by introducing cysteine residues at the 1 and 3 sites and four histidine residues at the C-terminal, respectively. The engineered functional groups of cysteine and histidine in the TMVCP and the self-assembly conditions determine the thermodynamics and kinetics in the self-assembly process for forming different crystal structures. The results show that the TMVCPs are thermodynamically driven to form triclinic crystals due to the formation of disulfide bonds between neighboring TMVCPs. On the other hand, the self-assembly of HCP crystals is kinetically directed by the strong metal–histidine chelation. This work not only greatly expands TMVCP for fabricating promising nanomaterials but also represents an approach to adjusting the protein crystal structures by tuning the thermodynamics and kinetics during crystallization

Disulfide Bond: Dramatically Enhanced Assembly Capability and Structural Stability of Tobacco Mosaic Virus Nanorods

Tobacco mosaic virus (TMV) is a classical viral nanoarchitecture that has been extensively employed as a promising template for the fabrication of novel nanomaterials and nanostructures. Despite being an ideal source, the Escherichia coli-derived TMV nanorod is suffering from tenuous assembly capability and stability. Inspired by the disulfide bond widely employed in biosystems, here we rationally introduce a cysteine into TMV coat protein (TMV-CP) to enable disulfide bond formation between adjacent subunits, thereby radically altering the behaviors of original noncovalent assembling system of wild type TMV-CP. The dramatically enhanced self-assembly capability and stability of the engineered TMV nanorods are observed and the essential roles of disulfide bonds are verified, illustrating a promising strategy to obtain desired genetic-modified nanorods that are inaccessible in plants. We expect this work will benefit the development of TMV-based nanotechnology and encourage the utilization of disulfide bonds in other biomacromolecules for improved properties as nanoscaffolds

Bioactivity and structure-activity relationship of cinnamic acid esters and their derivatives as potential antifungal agents for plant protection

<div><p>A series of cinnamic acid esters and their derivatives were synthesized and evaluated for antifungal activities in vitro against four plant pathogenic fungi by using the mycelium growth rate method. Structure−activity relationship was derived also. Almost all of the compounds showed some inhibition activity on each of the fungi at 0.5 mM. Eight compounds showed the higher average activity with average EC₅₀ values of 17.4–28.6 μg/mL for the fungi than kresoxim-methyl, a commercial fungicide standard, and ten compounds were much more active than commercial fungicide standards carbendazim against <i>P</i>. <i>grisea</i> or kresoxim-methyl against both <i>P</i>. <i>grisea</i> and <i>Valsa mali</i>. Compounds <b>C1</b> and <b>C2</b> showed the higher activity with average EC₅₀ values of 17.4 and 18.5 μg/mL and great potential for development of new plant antifungal agents. The structure−activity relationship analysis showed that both the substitution pattern of the phenyl ring and the alkyl group in the alcohol moiety significantly influences the activity. There exists complexly comprehensive effect between the substituents on the phenyl ring and the alkyl group in the alcohol moiety on the activity. Thus, cinnamic acid esters showed great potential the development of new antifungal agents for plant protection due to high activity, natural compounds or natural compound framework, simple structure, easy preparation, low-cost and environmentally friendly.</p></div

EC₅₀ values of the compounds with higher initial activity against four strains of fungi.

<p>EC₅₀ values of the compounds with higher initial activity against four strains of fungi.</p

Additional file 1: Table S1. of Body surface area is a novel predictor for surgical complications following video-assisted thoracoscopic surgery for lung adenocarcinoma: a retrospective cohort study

Showed the details of definitions for preoperative comorbidities estimated in the current study. Table S2. showed the demographic differences between patients with BSA ≤ 1.68 m2 and patients with BSA > 1.68 m2. (DOCX 20 kb

Targeting the Sonic Hedgehog-Gli1 Pathway as a Potential New Therapeutic Strategy for Myelodysplastic Syndromes

<div><p>The complex mechanistic array underlying the pathogenesis of myelodysplastic syndrome (MDS) is still unclear. Although dysregulations of different signaling pathways involved in MDS have been described, the identification of specific biomarkers and therapy targets remains an important task in order to establish novel therapeutic approaches. Here, we demonstrated that the Shh signaling pathway is active in MDS and correlated it with disease progression. Additionally, the knockdown of Gli1 significantly inhibited cell proliferation <i>in vitro</i> and <i>in vivo</i>. Gli1 silencing also induced apoptosis and G0/G1 phase arrest. Furthermore, Gli1 silencing enhanced the demethylating effect of 5-aza-2'-deoxycytidine on the p15 gene promoter and subsequently promoted its expression by inhibiting DNA methyltransferase 1(DNMT1). Our findings show that the Shh signaling pathway plays a role in the pathogenesis and disease progression of MDS, and proceeds by modulating DNA methylation. This pathway may prove to be a potential therapeutic target for enhancing the therapeutic effects of 5-azacytidine on malignant transformation of MDS.</p></div

Primer sequences for real-time PCR.

<p>Primer sequences for real-time PCR.</p

Gli1 silencing enhanced the demethylating effect of 5-aza-dC on p15 and subsequently promoted p15 expression.

<p>(A). Relative expression of DNMT1 and p15 mRNA upon Gli1 knockdown was analyzed by real-time PCR. Expression levels of beta-actin (ACTB), used as a housekeeping gene, were taken as control. Fold-change was calculated with the 2^−ΔΔCt method compared with controls. All experiments were performed in triplicate and the results are expressed as average ± SEM. *P < 0.05. (B). Western blot analysis of the effects of Gli1 knockdown on DNMT1 and p15 protein expression. Each sample was normalized to the respective related beta-actin (ACTB) expression. (C). Methylation-specific PCR for identification of changes in the methylation status of p15 promoter in MUTZ-1 cells transfected with sh-Gli1 (Gli1 sh1 and Gli1 sh2) and control lentiviral vector (Scramble) treated with or without 5-aza-dC (2 μM) for 48h. Images represent PCR-amplified products separated on 2% agarose gels and visualized under UV light after staining with ethidium bromide.</p