Fig. 2.

Fig. 2.

Transcriptomic profiling of zebrafish iridophores reveals lysosome-related organelle (LRO) signatures. (A) Volcano plot showing differentially expressed genes between sorted iridophores (n = 3) and a heterogeneous control cell population (n = 3) from zebrafish larvae at 5 dpf. Genes with P < 0.05 and fold change >2 are highlighted in pink. Selected iridophore markers are highlighted by blue dots. (B) Bar plot illustrating elevated expression of canonical iridophore marker genes, including pnp4a, tfec, and gmps. (C) Gene pathways enrichment analysis performed using Metascape (69), showing significant upregulation of pathways related to lysosomes, vesicle organization, and pigment granule biogenesis (pink bars). (D) STRING (70) (https://string-db.org/) interaction network of LRO-associated genes significantly upregulated in iridophores. The network was clustered using the k-means algorithm into three distinct clusters: BLOC and HPS complexes (green), Rab and VPS proteins (red), and AP complexes (blue) and visualized using Cytoscape (71). (E) Bar graph showing the over expression levels of a consensus set of LRO marker genes in iridophores. (F) Distribution of the standardized LRO gene expression in iridophores vs. control cells. Iridophores show a significantly higher expression of LRO genes, supporting their classification as LRO-bearing cells. Significance determined by Student’s test, two tailed, unpaired, ****P < 0.0001.