Observation and Analysis of in vitro Expression of Mouse Heart Nuclear DNA Fragments by AFM

Using AFM,we observed linear chain-like complexes formed by some specific proteins and the multi-mRNAs during the in vitro expression of some active genes on the DNA fragments. The LDH mRNA in the multi-mRNA complex can in vitro translate LDH. Via AFM, we also discovered that nmRNA prepared from heart muscles, along with some specific proteins can form linear chain-like nmRNA complexes in which LDH mRNA can also translate LDH in vitro. Our work shows the prospective application of AFM in the research of the biological reaction of the active genes on the DNA fragments.

Vibramycin inhibits the expression of MMP-2 and the invasiveness of PC-3 cells in vitro

Objective To study the inhibition of vibramycin on the expression of matrix metalloproteinase-2 (MMP-2) and the invasiveness of androgen-independent prostatic carcinoma cell line PC - 3 in vitro. Methods Immunohistochemistry stain and transwell chamber were used to investigate the expression of MMP-2 in different concentration of vibramycin treated PC-3 cells and the invasive ability of different concentration of vibramycin treated PC-3 cell. Results The positive rate of MMP-2 inJune 2003 Vol12 No2 PC-3 cells was decreased at a concentration of 5 mg/L of vibramycin and decreased dramatically at the concentration of 10 mg/L. The cells moved throuth the membrane was(82. 0 ± 4.6)/field in the control group, while decreased to(26.1 ±3.6),(7.2 ±2.2) and(3.3± 0.7)/field in 5,10 and 20 mg/L vibramycin treated PC-3 cell respectively. Conclusion Vibramycin can inhibit the invasiveness and metastatasis of PC-3 cells, the mechanism of which is related to the inhibition of MMP-2 in PC-3 cell.10refs.

Molecular and functional characterization of three novel carboxylesterases in the detoxification of permethrin in the mosquito, Culex quinquefasciatus

Carboxylesterases (CarEs) belong to a super family of multifunctional enzymes associated with the degradation of endogenous and exogenous compounds. Many insect CarEs are known to play important roles in catalyzing the hydrolysis of organophosphates (OPs), carbamates, and synthetic pyrethroids (SPs). The elevation of esterase activity through gene amplification and overexpression of estα2 and estβ2 genes contributes to the development of resistance to OP insecticides in the mosquito Culex quinquefasciatus. Three additional CarE genes are upregulated in permethrin-resistant Cx. quinquefasciatus according to an RNA-seq analysis, but their function remains unknown. In this study, we, for the first time, characterized the function of these three novel genes using in vitro protein expression, an insecticide metabolism study and molecular docking analysis. All three CarE genes were significantly overexpressed in resistant mosquito larvae, but not adults, compared to susceptible strain. No gene copy differences in these three genes were found in the mosquitoes tested. In vitro high-performance liquid chromatography (HPLC) revealed that CPIJ018231, CPIJ018232, and CPIJ018233 metabolized 30.4% ± 2.9%, 34.7% ± 6.8%, and 23.2% ± 2.2% of the permethrin, respectively. No mutations in resistant strains might significantly affect their CarE hydrolysis ability. A docking analysis further confirmed that these three CarEs from resistant strain all potentially metabolize permethrin. Taken together, these three carboxylesterase genes could play important roles in the development of permethrin resistance in Cx. quinquefasciatus larvae through transcriptional overexpression, metabolism, and detoxification.