Intra-follicle microinjection of shRNA lentiviral particles for the study of mechanotransduction in whisker hair follicles. A-B) The experimental setting for intra-follicle microinjection. B is the enlarged image in the boxed region in A. The main instruments used for intra-follicle microinjection include a dissection microscope (DM), a stereotaxic instrument (SI), a microinjector (MI) and microinjector controller (MIC), an isoflurane anesthesia machine with its nose cone (NC), a microsyringe (MS), a forceps (FO), and a glass microelectrode (GM). C-D) Images show the exposure of the front part of a whisker hair follicle by gently lifting the whisker hair using a forceps. The forceps is anchored on the stereotaxic instrument as shown in (B). D is the close-up image of the front part of the hair follicle (arrow indicated). E) Insertion of the glass microelectrode into the whisker hair follicle. The tip of the glass microelectrode was vertically advanced 1.5 mm deep into the whisker hair follicle. The glass microelectrode was filled with 10 μl Piezo2 shRNA lentiviral particle solution. The solution at the amount of 1 μl was microinjected into each whisker hair follicle. F-G) Completion of microinjection (F) and after withdrawal of the glass microelectrode. After the completion of the microinjection, the glass microelectrode remains within the whisker hair follicle for an additional 10 min before being withdrawn from the whisker hair follicle. H) Seven days after the microinjection of Piezo2 shRNA lentiviral particle solution, whisker hair follicle preparations were made for patch-clamp recordings of MA currents from Merkel cells.