Research Progress on Structure-Activity Relationship of 1,8-Naphthalimide DNA Chimeras Against Tumor.

The development of 1,8-naphthalimide derivatives as cell probes, DNA targeting agents, and anti-tumor drugs is one of the research hotspots in the field of medicine. Naphthalimide compounds are a kind of DNA embedder, which can change the topological structure of DNA by embedding in the middle of DNA base pairs, and then affect the recognition and action of topoisomerase on DNA. Aminofide and mitonafide are the first 2 drugs to undergo clinical trials. They have good DNA insertion ability, can embed DNA double-stranded structure, and induce topoisomerase II to cut part of pBR322DNA, but not yet entered the market due to their toxicity. In this paper, the design and structure-activity relationship of mononaphthalimide and bisaphthalimide compounds were studied, and the relationship between the structure of naphthalimide and anti-tumor activity was analyzed and discussed. It was found that a variety of structural modifications were significant in improving anti-tumor activity and reducing toxicity.

The northern corn leaf blight resistance gene Ht1 encodes an nucleotide-binding, leucine-rich repeat immune receptor.

Northern corn leaf blight, caused by the fungal pathogen Exserohilum turcicum, is a major disease of maize. The first major locus conferring resistance to E. turcicum race 0, Ht1, was identified over 50 years ago, but the underlying gene has remained unknown. We employed a map-based cloning strategy to identify the Ht1 causal gene, which was found to be a coiled-coil nucleotide-binding, leucine-rich repeat (NLR) gene, which we named PH4GP-Ht1. Transgenic testing confirmed that introducing the native PH4GP-Ht1 sequence to a susceptible maize variety resulted in resistance to E. turcicum race 0. A survey of the maize nested association mapping genomes revealed that susceptible Ht1 alleles had very low to no expression of the gene. Overexpression of the susceptible B73 allele, however, did not result in resistant plants, indicating that sequence variations may underlie the difference between resistant and susceptible phenotypes. Modelling of the PH4GP-Ht1 protein indicated that it has structural homology to the Arabidopsis NLR resistance gene ZAR1, and probably forms a similar homopentamer structure following activation. RNA sequencing data from an infection time course revealed that 1 week after inoculation there was a threefold reduction in fungal biomass in the PH4GP-Ht1 transgenic plants compared to wild-type plants. Furthermore, PH4GP-Ht1 transgenics had significantly more inoculation-responsive differentially expressed genes than wild-type plants, with enrichment seen in genes associated with both defence and photosynthesis. These results demonstrate that the NLR PH4GP-Ht1 is the causal gene underlying Ht1, which represents a different mode of action compared to the previously reported wall-associated kinase northern corn leaf blight resistance gene Htn1/Ht2/Ht3.

Study of the Effect Epidermal Growth Factor Nanoparticles in the Treatment of Diabetic Rat Ulcer Skin and Regeneration.

This study's objective is to analyze the effect of epidermal growth factor (EGF) nanoparticles on the healing of diabetic skin wounds and also, simultaneously, to investigate the mechanism of EGF nanoparticles to promote healing. In this manuscript, EGF nanoparticles were prepared, and also the drug loading rate of EGF nanoparticles was measured. In the meantime, a diabetic skin wound model was prepared with the use of rats. Then, the rats were split into four groups: EGF nanogroup, EGF group, empty particle group, and control group. Additionally, the results indicate that this study was successful in preparing EGF nanoparticles with a stable performance, and the drug was released for 24 hours. The wound healing in the EGF nanoparticle group was quicker than that in the EGF group. Furthermore, the area of EGF receptor-positive cells in the wound surface of the EGF nanogroup was higher than that of the EGF group, with the results demonstrating that EGF nanoparticles upregulated the expression of EGF receptors in wound surface cells, promoted wound surface healing, and had better efficacy than EGF.

Identification and Evaluations of Novel Insecticidal Proteins from Plants of the Class Polypodiopsida for Crop Protection against Key Lepidopteran Pests.

Various lepidopteran insects are responsible for major crop losses worldwide. Although crop plant varieties developed to express Bacillus thuringiensis (Bt) proteins are effective at controlling damage from key lepidopteran pests, some insect populations have evolved to be insensitive to certain Bt proteins. Here, we report the discovery of a family of homologous proteins, two of which we have designated IPD083Aa and IPD083Cb, which are from Adiantum spp. Both proteins share no known peptide domains, sequence motifs, or signatures with other proteins. Transgenic soybean or corn plants expressing either IPD083Aa or IPD083Cb, respectively, show protection from feeding damage by several key pests under field conditions. The results from comparative studies with major Bt proteins currently deployed in transgenic crops indicate that the IPD083 proteins function by binding to different target sites. These results indicate that IPD083Aa and IPD083Cb can serve as alternatives to traditional Bt-based insect control traits with potential to counter insect resistance to Bt proteins.

MicroRNAs: potential biomarkers for disease diagnosis.

MicroRNAs (miRNAs) are a group of endogenous noncoding small RNAs characterized by high conservation; furthermore, various studies have shown the capability of miRNAs to impact diseases. For example, a study shows that cell-free miRNAs are stable in bodily fluids, which gives circulating miRNAs the ability to be potential biomarkers for noninvasive diagnosis. Additionally, accumulating studies have supported that miRNAs can function as suppressor genes, again demonstrating their effect on disease. This review introduces this particular role of miRNAs as well as analyzes the prospect of miRNAs as biomarkers and the capacity for using miRNA-based resources to benefit mankind.