Activities of 58 miRNAs for BHK21, HEK293, and Vero cell lines were screened using the high-throughput miRNA activity profiling method. miR-206 activity was found specifically high in BHK21. Considering miR-206 was recognized as a muscle-specific miRNA, we further detected the expression and activity level of miR-206 in BHK21 cells, with myoblast cells C2C12 as positive control and HEK293 cells as negative control. Then, we induced BHK21 by culturing with medium containing 2% horse serum (HS) and tested expression level of slow skeletal myosin heavy chain (MHC), activity and expression levels of miR-206, and expression level of Connexin43 (Cx43) which was reported negatively regulated by miR-206. Results demonstrated that activity and expression levels of miR-206 were both higher in BHK21 cells than in C2C12 cells. After induction of HS, MHC expression level was increased in BHK21 cells. The activity and expression levels of miR-206 were further enhanced. The Cx43 expression level was decreased. These results suggested that BHK21 had the characters of myoblast cells. In conclusion, we firstly discovered that miR-206 activity was specifically high in BHK21 cells, suggesting that BHK21 cells were derived from interstitial cells other than parenchyma cells of kidney from miRNA point of view. Our study also indicated that BHK21 cells were able to be used as models in vitro for research of miR-206 function.
Animals ; Cell Line ; Cercopithecus aethiops ; Connexin 43 ; metabolism ; Cricetinae ; Gene Expression Regulation ; HEK293 Cells ; Humans ; MicroRNAs ; genetics ; Myosin Heavy Chains ; metabolism ; Vero Cells

Loofah seeds ribosome inactivating protein luffin-α was fused with a tumor-targeting peptide NGR to create a recombinant protein, and its inhibitory activity on tumor cells and angiogenesis were assessed. luffin-α-NGR fusion gene was obtained by PCR amplification. The fusion gene was ligated with pGEX-6p-1 vector to create a recombinant plasmid pGEX-6p-1/luffin-α-NGR. The plasmid was transformed into E. coli BL21, and the target protein was isolated and purified by GST affinity chromatography. The luffin-α-NGR fusion gene with a full length of 849 bp was successfully obtained, and the optimal soluble expression of the target protein was achieved under the conditions of 16 ℃, 0.5 mmol/L IPTG after 16 h induction. SDS-PAGE and Western blotting confirmed the recombinant protein has an expected molecular weight of 56.6 kDa. Subsequently, the recombinant protein was de-tagged by precision protease digestion. The inhibitory effects of the recombinant protein on liver tumor cells HepG2 and breast cancer cells MDA-MB-231 were significantly stronger than that of luffin-α. The Transwell and CAM experiment proved that the recombinant protein luffin-α-NGR also had a significant inhibitory effect on tumor cells migration and neovascularization. The inhibitory activity on tumor cells and angiogenesis of the recombinant luffin-α-NGR protein lays a foundation for the development of subsequent recombinant tumor-targeting drugs.
Electrophoresis, Polyacrylamide Gel ; Escherichia coli/metabolism* ; Plasmids ; Recombinant Proteins/pharmacology* ; Saporins/metabolism*