Fig. 4

The mandible regulated tooth germ development through exosome-transferred ssc-mir-133b. a Apoptosis was measured with a TUNEL assay in E30 and E35 mandibles. Red arrowheads represent dental lamina. Scale bar = 200 μm. ***P < 0.001. b In situ hybridization of ssc-mir-133b in E30, E35, E40 and E50 mandibles. Scale bar = 200 μm. c Exosome characterization by transmission electron microscopy (left) and Western blotting (right). Scale bar = 50 nm. Calnexin is an endoplasmic reticulum marker and Alix and CD63 are exosome markers. d qPCR for ssc-mir-133b levels in E35 tooth germ and mandible. ***P < 0.001. e qPCR for ssc-mir-133b levels in E35 tooth germ and mandible exosomes. ***P < 0.001. f Transwell culture of tooth germ and mandible or mandible exosomes in vitro. g qPCR for ssc-mir-133b levels in tooth germ and mandible or mandible exosomes after Transwell culture. ***P < 0.001