Abstract
Zebrafish display a prominent pattern of alternating dark and light stripes generated by the precise positioning of pigment cells in the skin. This arrangement is the result of coordinated cell movements, cell shape changes, and the organisation of pigment cells during metamorphosis. Iridophores play a crucial part in this process by switching between the dense form of the light stripes and the loose form of the dark stripes. Adult schachbrett (sbr) mutants exhibit delayed changes in iridophore shape and organisation caused by truncations in Tight Junction Protein 1a (ZO-1a). In sbr mutants, the dark stripes are interrupted by dense iridophores invading as coherent sheets. Immuno-labelling and chimeric analyses indicate that Tjp1a is expressed in dense iridophores but down-regulated in the loose form. Tjp1a is a novel regulator of cell shape changes during colour pattern formation and the first cytoplasmic protein implicated in this process.
Highlights
One of the most fascinating features of vertebrates is their display of remarkable colour patterns in skin, fur, or plumage, frequently varying strikingly between closely related species
Metamorphic xanthophores originate from larval xanthophores, they compact over the dense iridophores of the light stripe and change into a pale stellate shape above the loose iridophores and melanophores of the dark stripe (Mahalwar et al, 2014)
We show that Tjp1a-deficient fish develop multiple interruptions of the dark stripes in the trunk by light stripe structures composed of dense iridophores covered by compact xanthophores
Summary
One of the most fascinating features of vertebrates is their display of remarkable colour patterns in skin, fur, or plumage, frequently varying strikingly between closely related species. The mutant fish appear spotted rather than striped, because light regions containing sheets of the dense iridophores interrupt the dark stripes. Tjp1a is likely to regulate how colour patterns form by controlling how iridophores interact with other types of pigment cell. Metamorphic xanthophores originate from larval xanthophores, they compact over the dense iridophores of the light stripe and change into a pale stellate shape above the loose iridophores and melanophores of the dark stripe (Mahalwar et al, 2014). Dense iridophores invade the dark stripe regions and temporarily suppress the expansion of melanophores, suggesting that Tjp1a is required to regulate the transition of dense iridophores into the loose shape and their organisation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
