Fig. 3

Characterization of cellular identities of osteogenic and non-osteogenic mesenchymal progenitors. (a) Schematic illustration of the experimental procedure. Cre/loxP recombination was performed at 0?1 dpf. Adult fin rays (10?20 fin rays) with respective lineage labeling were manually dissected. The dissociated cells were subjected to fluorescence-activated cell sorting to collect OMPs and non-OMPs. (b) Representative examples of cell sorting of OMPs (upper panel) and non-OMPs (lower panel). The respective plots contained 500,000 events excluding dead cells and debris. RNA was isolated from non-OMPs (green circles in the lower panel), OMPs (green circles in the upper panel), and osteoblasts (orange circles in the upper panel). (c) Cluster heatmap of normalized expression data for enriched genes in non-OMPs (91 genes), OMPs (58 genes), and osteoblasts (111 genes). Enriched genes were identified using the following parameters: TPM value (average of two independent experiments) > 10 and fold change > 5. Representative genes associated with chondroblastic and osteoblastic differentiation are indicated on the left side. OMP-enriched genes were divided into two groups, one specific to OMPs (group 2) (Table S2) and the other containing OMP/osteoblast (OB)-enriched genes (group 3) (Table S3). (d) Gene Ontology (GO) enrichment analysis of non-OMP, OMP, OMP/osteoblast, and osteoblast genes. The top five enriched GO terms in the biological process category are shown. Terms related to chondrogenic and osteogenic profiles are indicated in red. Fisher's exact test was used (p < .05). Non-OMPs apparently exhibit chondrogenic identity.