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Background: Color and pattern phenotypes have clear implications for survival and reproduction in many species. However, the mechanisms that produce this coloration are still poorly characterized, especially at the genomic level. Here we have taken a transcriptomics-based approach to elucidate the underlying genetic mechanisms affecting color and pattern in a highly polytypic poison frog. We sequenced RNA from the skin from four different color morphs during the final stage of metamorphosis and assembled a de novo transcriptome. We then investigated differential gene expression, with an emphasis on examining candidate color genes from other taxa. Results: Overall, we found differential expression of a suite of genes that control melanogenesis, melanocyte differentiation, and melanocyte proliferation (e.g., tyrp1, lef1, leo1, and mitf) as well as several differentially expressed genes involved in purine synthesis and iridophore development (e.g., arfgap1, arfgap2, airc, and gart). Conclusions: Our results provide evidence that several gene networks known to affect color and pattern in vertebrates play a role in color and pattern variation in this species of poison frog.
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Neon tetra fish (Paracheirodon innesi) as farm-to-optical-table Bragg reflectors
Iridophore networks in the skin of neon tetra fish are investigated for use as biologically sourced, tunable, Bragg reflector arrays. This paper reports on a method for immediate and fast post-processing of tissue to modify the structural color of iridophores found in the lateral color stripe. Conditions for fixation, as well as the environment post-fixation to improve longevity of the structural color, are also presented. Recent results from attempts to further increase the lifetime of post-mortem iridophore color through infiltration and embedding in low-acid glycol methacrylate are also discussed.
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- Award ID(s):
- 2337595
- PAR ID:
- 10526974
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Journal of the Optical Society of America B
- Volume:
- 41
- Issue:
- 11
- ISSN:
- 0740-3224; JOBPDE
- Format(s):
- Medium: X Size: Article No. D24
- Size(s):
- Article No. D24
- Sponsoring Org:
- National Science Foundation
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