Comprehensive Transcriptome Analysis of Different Skin Colors to Evaluate Genes Related to the Production of Pigment in Celestial Goldfish

Abstract

Skin color is an important phenotypic feature of vertebrate fitness under natural conditions. Celestial goldfish, a common goldfish breed in China, mainly shows three kinds of skin colors including white, yellow and brown. However, the molecular genetic basis of this phenotype is still unclear. In this study, high-throughput sequencing was carried out on the back skin tissues of celestial goldfish with different skin colors. About 58.46 Gb of original data were generated, filtered and blasted, and 74,297 mRNAs were obtained according to the reference transcriptome. A total of 4653 differentially expressed genes were screened out among the brown, yellow and white groups, and the expression of melanogenesis related genes in brown goldfish was significantly higher than the other two groups. There are 19 common differentially expressed genes among three groups, of which eight genes are related to pigment production, including tyrp1a, slc2a11b, mlana, gch2, loc113060382, loc113079820, loc113068772 and loc113059134. RT-qPCR verified that the expression patterns of randomly selected differentially expressed transcripts were highly consistent with those obtained by RNA sequencing. GO and KEGG annotation revealed that these differentially expressed genes were mostly enriched in pathways of the production of pigment, including melanogenesis, tyrosine metabolism, Wnt signaling pathway, MAPK signaling pathway etc. These results indicated that the external characteristics of goldfish are consistent with the analysis results at transcriptome level. The results of this study will lay a foundation for further study on the expression characteristics and gene network analysis of pigment related genes.

Uridine Diphosphate Glycosyltransferases (UGTs) Involved in the Carotenoid-Based Body Color Difference between Tetranychus cinnabarinus (Red) and Tetranychus urticae (Green)

“…Insect color differentiation has been linked to numerous factors, including gene expression levels, material transformation and flow distribution, and other synthetic pigments [3][4][5][6]. In genetically similar species, differences in gene expression can result in genotypic variation, e.g., differential expression or the deletion of pigment-related genes can cause phenotypic polymorphisms [7,8]. Carotenoids make up most of the mite pigment composition [9].…”

Study on Physiological and Biochemical Index of Blood and Vitreous Humor in the Celestial Goldfish (<em>Carassius auratus</em>)

“…This goldfish was a favorite in the imperial palace during the Qing dynasty since its name originally meant "looking upward to the Son of Heaven" [2]. So far, few studies have been done on celestial goldfish, much of which has focused on their genetics and body color [3][4][5]. Some reports have also suggested that celestial goldfish have a degenerated retina and weak vision [6,7], making them suitable as model animals for the study of human eye diseases [8].…”