and primary BJ cells. Additionally, we also found that for a
different set of MBs with unique stem and loop lengths and
sequences, the 2Me/PSLOOParchitecture also generated the
least false-positive signals in HeLa cells. This suggests that the
advantages of the 2Me/PSLOOPdesign can be generalized to
other MB sequences.- Slowly pipette the target RNA solution into the microinjection
capillary to avoid creating air bubbles. - Compensation pressure is necessary to avoid entry of cell cul-
ture media into the injection capillary, which can dilute the
probe. - Injection parameters and amounts vary with different cell
types. The operator should adjust as necessary. - Figure3 shows injection of excess targets at 8 and 24 h post-
microporation of the 2Me/PSLOOPMBs, 2Me MBs, or 2Me/
PSFULLMBs. Signal enhancement was significantly greater for
the 2Me/PSLOOP MBs as compared with 2Me and 2Me/
PSFULLMBs. Thus, in addition to being less susceptible to
nonspecific opening, the 2Me/PSLOOPMB was also more
functionally active in living cells.
Acknowledgments
This project was supported by grants from the National Basic
Research Program of China (2016YFA0100702), the National
Natural Science Foundation of China (81371613), and the Beijing
Natural Science Foundation (7162114).References
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