FIGURE 1.

Mouse embryo palate dissection and quantification method for palate fusion. (A) Under the stereomicroscope, mouse embryos were examined to confirm the embryonic stage E13.5 based on Theiler's stages criteria [96]. Each embryo was placed in one drop of cold PBS in a petri dish. To isolate the upper jaw, two transversal cuts were made; one just below the eye level and over the ears and the second from the oral commissures to below the ears. (B) Once the upper jaw is isolated, the oral side is orientated up and the surrounding tissue is carefully removed. PP: primary palate. PS: Palate shelves. UL: Upper lip. (C) In order to maintain the in vivo position of the palatal shelves, some tissue anterior and posterior to the shelves was left. (D) The dissected palates are carefully transferred to a well in a 6‐well plate, containing a stainless mesh with a filter on top and 3.5 ml of medium. 6W: well from a 6‐well plate. M: Stainless‐steel mesh. MF: 8 μM pore MF‐Millipore membrane filter. (E) Diagram showing the quantification of palate fusion on a histological section. OS: Oral side. b: Total thickness of the palate. a: part of the palate fused. NC: Nasal cavity. FP: Fusion percentage