Full-Length Transcriptome of <i>Camellia japonica</i> (Naidong) Reveals Molecular Characteristics in Drought Stress

Camellia japonica (Naidong), a rare temperate arbor in the genus Camellia, is an ornamental plant with high economic value. To understand transcriptional changes of the drought response in C. japonica, a comparative transcriptome analysis of C. japonica (Naidong) was conducted at two drought stages (0 and 20 DAF) based on the PacBio platform. The results showed significant differences in 265 genes and 3383 lncRNAs. Of these, 150 were upregulated and 115 were downregulated. Functional analysis revealed the involvement of distinct genes in 43 pathways. The biosynthesis of amino acids and the circadian rhythm of the plant were significantly enriched, with a significant change in CjGST potentially playing an important role under drought stress. In addition, three differential protein interaction network modules composed of 45 differentially expressed genes were predicted, which involved E3 ubiquitin ligases and threonine synthetic proteins. Moreover, a transient expression experiment demonstrated that overexpression of CjGST1 in camellia leaves significantly increased leaf area compared to wild variants under drought stress, resulting in higher drought resistance. These findings provide a valuable resource for studying the genus Camellia while shedding new light on the molecular mechanisms of drought stress

Pyrethroid resistance status and co-occurrence of V1016G, F1534C and S989P mutations in the Aedes aegypti population from two dengue outbreak counties along the China-Myanmar border

Abstract Background Over the past two decades, dengue fever (DF) has emerged as a significant arboviral disease in Yunnan province, China, particularly in the China-Myanmar border area. Aedes aegypti, an invasive mosquito species, plays a crucial role in transmitting the dengue virus to the local population. Insecticide-based vector control has been the primary tool employed to combat DF, but the current susceptibility status of Ae. aegypti to commonly used insecticides is unknown. Assessment of Ae. aegypti resistance to pyrethroid insecticides and an understanding of the underlying mechanisms of this resistance in the China-Myanmar border region is of significant strategic importance for effectively controlling the DF epidemic in the area. Methods Aedes aegypti larvae collected from Ruili and Gengma counties in Yunnan Province were reared to adults in the laboratory and tested for susceptibility to three pyrethroid insecticides (3.20% permethrin, 0.08% lambda-cyhalothrin and 0.20% deltamethrin) by the standard WHO susceptibility bioassay. Genotyping of mutations in the knockdown gene (kdr), namely S989P, V1016G and F1534C, that are responsible for resistance to pyrethroid insecticides was performed using allele-specific PCR methods. A possible association between the observed resistant phenotype and mutations in the voltage-gated sodium channel gene (VGSC) was also studied. Results Aedes aegypti mosquitoes collected from the two counties and reared in the laboratory were resistant to all of the pyrethroids tested, with the exception of Ae. aegypti from Gengma County, which showed sensitivity to 0.20% deltamethrin. The mortality rate of Ae. aegypti from Ruili county exposed to 3.20% permethrin did not differ significantly from that of Ae. aegypti from Gengma County (χ 2 = 0.311, P = 0.577). By contrast, the mortality rate of Ae. aegypti from Ruili County exposed to 0.08% lambda-cyhalothrin and 0.20% deltamethrin, respectively, was significantly different from that of Ae. aegypti from Gengma. There was no significant difference in the observed KDT50 of Ae. aegypti from the two counties to various insecticides. Four mutation types and 12 genotypes were detected at three kdr mutation sites. Based on results from all tested Ae. aegypti, the V1016G mutation was the most prevalent kdr mutation (100% prevalence), followed by the S989P mutation (81.6%) and the F1534C mutation (78.9%). The constituent ratio of VGSC gene mutation types was significantly different in Ae. aegypti mosquitoes from Ruili and those Gengma. The triple mutant S989P + V1016G + F1534C was observed in 274 Ae. aegypti mosquitoes (60.8%), with the most common genotype being SP + GG + FC (31.4%). The prevalence of the F1534C mutation was significantly higher in resistant Ae. aegypti from Ruili (odds ratio [OR] 7.43; 95% confidence interval [CI] 1.71–32.29; P = 0.01) and Gengma (OR 9.29; 95% CI 3.38–25.50; P = 0.00) counties than in susceptible Ae. aegypti when exposed to 3.20% permethrin and 0.08% lambda-cyhalothrin, respectively. No significant association was observed in the triple mutation genotypes with the Ae. aegypti population exposed to 3.20% permethrin and 0.20% deltamethrin resistance (P > 0.05), except for Ae. aegypti from Gengma County when exposed to 0.08% lambda-cyhalothrin (OR 2.86; 95% CI 1.20–6.81; P = 0.02). Conclusions Aedes aegypti from Ruili and Gengma counties have developed resistance to various pyrethroid insecticides. The occurrence of multiple mutant sites in VGSC strongly correlated with the high levels of resistance to pyrethroids in the Ae. aegypti populations, highlighting the need for alternative strategies to manage the spread of resistance. A region-specific control strategy for dengue vectors needs to be implemented in the future based on the status of insecticide resistance and kdr mutations. Graphical Abstrac

Phenylboronic Acid-Modified Gold Nanoclusters as a Nanoantibiotic to Treat Vancomycin-Resistant <i>Enterococcus faecalis</i>-Caused Infections

Vancomycin is one of the last lines of defense against certain drug-resistant bacteria-caused infections. However, the high susceptibility to drug resistance and high toxicity seriously limit the application of vancomycin. Nanoantibiotics provide opportunities to solve these problems. Herein, we present mercaptophenylboronic acid (MBA)-modified gold nanoclusters with well-defined molecular formulas and structure (Au44(MBA)18) and excellent antibacterial activities against various drug-resistant bacteria such as vancomycin-resistant Enterococcus faecalis (VRE). Au44(MBA)18 interacts with bacteria by first attaching to teichoic-acid and destroying the cell wall and subsequently binding to the bacterial DNA. Au44(MBA)18 could be administered via multiple routes and has a high biosafety (500 mg/kg, no ototoxicity), overcoming the two major shortcomings of vancomycin (sole administration route and high ototoxicity). Our study is insightful for curing infections caused by multidrug-resistant bacteria using nanoantibiotics with high biosafety