RESUMEN

Mosquitoes form a vital group of vector insects, which can transmit various diseases and filarial worms. The cuticle is a critical structure that protects mosquitoes from adverse environmental conditions and penetration resistance. Thus, cuticle proteins can be used as potential targets for controlling the mosquito population. In the present study, we found that AaCPR100A is a structural protein in the soft cuticle, which has flexibility and elasticity allowing insects to move or fly freely, of Aedes aegypti. RNA interference (RNAi) of AaCPR100A caused high mortality in Aedes aegypti larvae and adults and significantly decreased the egg hatching rate. Transmission electron microscopy (TEM) analysis revealed that the larval microstructure had no recognizable endocuticle in AaCPR100A-deficient mosquitoes. A yeast two-hybrid assay was performed to screen proteins interacting with AaCPR100A. We verified that the G12-like protein had the strongest interaction with AaCPR100A using yeast two-hybrid and GST pull-down assays. Knockdown of G12-like transcription resulted in high mortality in Ae. aegypti larvae, but not in adults. Interestingly, RNAi of G12-like rescued the high mortality of adults caused by decreased AaCPR100A expression. Additionally, adults treated with G12-like dsRNA were found to be sensitive to low temperature, and their eggshell formation and hatching were decreased. Overall, our results demonstrated that G12-like may interacts with AaCPR100A, and both G12-like and AaCPR100A are involved in Ae. aegypti cuticle development and eggshell formation. AaCPR100A and G12-like can thus be considered newly potential targets for controlling the Ae. aegypti mosquito.

Asunto(s)

Aedes , Proteínas de Insectos , Animales , Aedes/genética , Aedes/metabolismo , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Larva/metabolismo , Larva/crecimiento & desarrollo , Interferencia de ARN , Unión Proteica , Técnicas del Sistema de Dos Híbridos

RESUMEN

Long-chain fatty acid elongases (ELOs) play important roles in the metabolism of fatty acids in insects. In this study, the genes for two elongases from Aedes aegypti were identified, AeELO2 and AeELO9. Quantitative real time PCR showed that AeELO2 and AeELO9 are expressed at all developmental stages and some body parts, but with different expression patterns. RNAi-mediated knockdown of AeELO2 and AeELO9 was performed to investigate their roles in the development, growth, osmotic balance, and cold tolerance of Ae. aegypti. Knockdown of AeELO2 slowed larval growth and development by causing molting abnormalities. Additionally, 33% ± 3.3% of adults died during oviposition, accompanied by an abnormal extension of cuticles in AeELO2-dsRNA knockdown mosquitos. Knockdown of AeEL09 resulted in abnormal balance of cuticular osmotic pressure and a reduction in egg production. The maximal mRNAs of AeELO2 and AeELO9 were detected in eggs at 72 h after oviposition. Moreover, AeELO2 knockdown reduced the egg hatching rates and AeELO9 knockdown larvae did not develop well. In summary, AeELO2 is involved in larval molting and growth, and its knockdown affects the flexibility and elasticity of adult mosquito cuticles. AeELO9 regulates cold tolerance, osmotic balance, and egg development in Ae. aegypti.

RESUMEN

@#Abstract: Objective To construct a shuttle vector pHT315-AaCPR100A with two spore-producing-dependent promoters and the target gene AaCPR100A in Escherichia coli-Bacillus thuringiensis. Methods The forward promoter of Cry3A, named Pro-1 (+), was amplified by PCR using pSVP27A plasmid as the template, and the target gene AaCPR100A was amplified using Aedes aegypti RNA reverse conversion cDNA as the template. The plasmid pHT315 was linearized by digestion with Hind Ⅲ and Sal Ⅰ. The forward promoter and the target gene were inserted into the linearized vector pHT315 successively by in-fusion cloning according to the transcription direction. The synthesized plasmid containing the Cry3A reverse promoter sequence was used as the template, and the Pro-1 (-) reverse promoter was amplified by PCR. The intermediate vector containing the forward promoter and the target gene was linearized by EcoR I restriction enzyme, and the reverse promoter was inserted downstream of the target gene by in-fusion cloning in the direction of transcription. Results By agarose gel electrophoresis, the forward promoter, target gene AaCPR100A and reverse promoter bands were clear and of good quality, which could be used for in-fusion cloning experiments. The two spore-producing-dependent promoters and target gene fragments were connected by In-fusion cloning. The recombinant vector pHT315-AaCPR100A was verified by PCR. The forward promoter, target gene fragment and reverse promoter were successfully amplified in the recombinant vector. Nucleotide sequencing verified that the sequencing results of the bidirectional promoter sequence and the target gene sequence were basically consistent with the sequence alignment results, which met the requirements of the construction of vector elements and proved that the recombinant vector was successfully constructed. Conclusions Based on the above results, this study proves that the recombinant shuttle vector with two spore-producing-dependent promoters can be successfully constructed by in-fusion cloning technology, laying the foundation for the construction of engineered Bacillus thuringiensis expressing dsRNA of AaCPR100A.

RESUMEN

Mycoplasma pneumoniae is a common atypical respiratory pathogen causing community-acquired pneumonia in children. Co-infection with other respiratory viruses is common in pediatric patients but super-infection with bacteria other than Streptococcus pneumoniae and Haemophilus influenzae is rare. The first case of Chromobacterium violaceum infection incubated during and manifested after pneumonia caused by Mycoplasma pneumoniae in a 12-month old girl without any known history of immunodeficiency is here reported. The patient developed fever with redness and swelling over the middle phalanx of the right hand index finger which progressed to the formation of skin abscess. Following a course of intravenous meropenem and surgical drainage of the skin abscess, the patient fully recovered and was discharged.