Cell-cell communication as underlying principle governing color pattern formation in fishes.

The diverse pigmentation patterns of animals are crucial for predation avoidance and behavioral display, yet mechanisms underlying this diversity remain poorly understood. In zebrafish, Turing models have been proposed to explain stripe patterns, but it is unclear if they apply to other fishes. In anemonefish (, we identified , a gene orthologous to zebrafish and encoding a connexin involved in pigment cell communication, as responsible for the phenotype. Using CRISPR/Cas9 and transgenesis, we recapitulate the phenotype and show expression of in iridophores. A matching allele was recovered in zebrafish, revealing complementary requirements in both species. Our findings highlight conserved roles of gap junction mediated communication in pigment patterning across divergent teleosts.