Transcriptome analysis of feather follicles reveals candidate genes and pathways associated with pheomelanin pigmentation in chickens

Xiaotong Zheng,Bo Zhang,Yawen Zhang,Haian Zhong,Hao Zhang,Junying Li,Ruixue Nie,Changxin Wu

doi:10.1038/s41598-020-68931-1

Xiaotong Zheng, Bo Zhang + Show 6 more

Open Access

https://doi.org/10.1038/s41598-020-68931-1

Copy DOI

Abstract

Yellow plumage is common in chickens, especially in breeds such as the Huiyang Bearded chicken, which is indigenous to China. We evaluated plumage colour distribution in F1, F2, and F3 populations of an Huiyang Bearded chicken × White Leghorn chicken cross, the heredity of the yellow plumage trait was distinguished from that of the gold plumage and other known plumage colours. Microscopic analysis of the feather follicles indicated that pheomelanin particles were formed in yellow but not in white feathers. To screen genes related to formation of the pheomelanin particles, we generated transcriptome data from yellow and white feather follicles from 7- and 11-week-old F3 chickens using RNA-seq. We identified 27 differentially expressed genes (DEGs) when comparing the yellow and white feather follicles. These DEGs were enriched in the Gene Ontology classes ‘melanosome’ and ‘melanosome organization’ related to the pigmentation process. Down-regulation of TYRP1, DCT, PMEL, MLANA, and HPGDS, verified using quantitative reverse transcription PCR, may lead to reduced eumelanin and increased pheomelanin synthesis in yellow plumage. Owing to the presence of the Dominant white locus, both white and yellow plumage lack eumelanin, and white feathers showed no pigments. Our results provide an understanding of yellow plumage formation in chickens.

Highlights

MethodsThe F1 population was obtained by crossing HB cocks with WL hens
There were 27 overlapping differentially expressed genes (DEGs) that occurred in both age groups (Supplementary Figure S5, Supplementary Table S4)
For the uniquely aligned sequences in the gene annotation files, the numbers and proportions of three functional elements were obtained: 76.37% ± 2.46% reads per sample were aligned to the mRNA region (Supplementary Figure S3)

Summary

Methods

The F1 population was obtained by crossing HB cocks with WL hens. Yellow plumage females and white plumage males were selected from the F1 population to produce an F2 population. Yellow plumage females and males were selected from the F2 population to produce an F3 population. For the transcriptome sequencing and to verify gene expression, five white plumage and five yellow plumage chickens were randomly collected from the F3 population, and several newly emerged feathers were plucked from nape of the neck at four time points (3, 5, 7 and 11 weeks of age). Yellow and white plumage chickens at 11 weeks of age were bled to death, and the newly emerged feather follicles, along with the nearby skin, were removed and fixed in 4% paraformaldehyde at 4 °C.

Results

Discussion

Conclusion