ABSTRACT
The Shitou goose, a highly recognized indigenous breed with gray plumage originating from Chaozhou Raoping in Guangdong Province, China, is renowned for being the largest goose species in the country. Notably, during the pure breeding process of Shitou geese, approximately 2% of the offspring in each generation unexpectedly exhibited white plumage. To better understand the mechanisms underlying white plumage color formation in Shitou geese, we conducted a comparative transcriptome analysis between white and gray feather follicles, aiming to identify key genes and microRNAs that potentially regulate white plumage coloration in this unique goose breed. Our results revealed a number of pigmentation genes, encompassing TYR, TYRP1, EDNRB2, MLANA, SOX10, SLC45A2, GPR143, TRPM1, OCA2, ASIP, KIT, and SLC24A5, which were significantly down-regulated in the white feather follicles of Shitou geese. Among these genes, EDNRB2 and KIT emerged as the most promising candidate genes for white plumage coloration in Shitou geese. Additionally, our analysis also uncovered 46 differentially expressed miRNAs. Of these, miR-144-y may play crucial roles in the regulation of feather pigmentation. Furthermore, the expression of novel-m0086-5p, miR-489-y, miR-223-x, miR-7565-z, and miR-3535-z exhibits a significant negative correlation with the expression of pigmentation genes including TYRP1, EDNRB2, MLANA, SOX10, TRPM1, and KIT, suggesting these miRNAs may indirectly regulate the expression of these genes, thereby influencing feather color. Our findings provide valuable insights into the genetic mechanisms underlying white plumage coloration in Shitou geese and contribute to the broader understanding of avian genetics and coloration research.