Fig. 3: Contributions of the LPM to the pectoral girdle and fin skeleton.

a, b Photoconversion of the LPM adjacent to somites 1–3 at the 10–12 somite stage (ss), viewed from the left lateral side (a) and in horizontal confocal section (b) (n = 9). Kaede-red is pseudo-colored in magenta. Asterisk in (a) shows the ectopically labeled optic vesicle. c–e At 72 hpf, parasagittal confocal sections obtained from mediolaterally different levels [lateral (c) to medial (e)] show that labeled cells are in the endoskeletal disc (n = 7/7), scapulocoracoid (n = 7/7), and (f) in the posterior half of the cleithrum (n = 5/7). g Contributions of the genetically labeled drl:creERT2 lineage cells to the osteoblasts of the cleithrum. The obtained embryos were subjected to in situ HCR with sp7 probe and DAPI staining. EGFP signal is raw fluorescence. Arrowheads in (g) point drl:creERT2 lineage cells expressing sp7 (n = 3).A anterior, ab abductor muscle, ad adductor muscle, ccv common cardinal vein, cle cleithrum, clehy cleithrohyoid muscle, D dorsal, ed endoskeletal disc, epi epidermis, ie inner ear, LPM lateral plate mesoderm, M medial, m1–2 myotomes 1–2, op operculum, P posterior, pa pharyngeal arches, phy posterior hypaxial muscle, s1–4 somites 1–4, sc scapulocoracoid. Scale bars: (a) 200 µm, (b–e) 50 µm, (g) 20 µm.