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Title: Nile Tilapia: A Model for Studying Teleost Color Patterns
Abstract The diverse color patterns of cichlid fishes play an important role in mate choice and speciation. Here we develop the Nile tilapia (Oreochromis niloticus) as a model system for studying the developmental genetics of cichlid color patterns. We identified 4 types of pigment cells: melanophores, xanthophores, iridophores and erythrophores, and characterized their first appearance in wild-type fish. We mutated 25 genes involved in melanogenesis, pteridine metabolism, and the carotenoid absorption and cleavage pathways. Among the 25 mutated genes, 13 genes had a phenotype in both the F0 and F2 generations. None of F1 heterozygotes had phenotype. By comparing the color pattern of our mutants with that of red tilapia (Oreochromis spp), a natural mutant produced during hybridization of tilapia species, we found that the pigmentation of the body and eye is controlled by different genes. Previously studied genes like mitf, kita/kitlga, pmel, tyrb, hps4, gch2, csf1ra, pax7b, and bco2b were proved to be of great significance for color patterning in tilapia. Our results suggested that tilapia, a fish with 4 types of pigment cells and a vertically barred wild-type color pattern, together with various natural and artificially induced color gene mutants, can serve as an excellent model system for study color patterning in vertebrates.  more » « less
Award ID(s):
1830753
PAR ID:
10655161
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Editor(s):
vonHoldt, Bridgett
Publisher / Repository:
Oxford
Date Published:
Journal Name:
Journal of Heredity
Volume:
112
Issue:
5
ISSN:
0022-1503
Page Range / eLocation ID:
469 to 484
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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