Whole-transcript Expression data from skin of different coat color in Chinese Merion (Junken type)

Coat color mainly reflects pigmentation resulting from melanin. Wool color is one of the most visible and heritable traits in sheep. Although several detailed molecular mechanisms involved in coat color have been elucidated, our understanding of differences in gene expression patterns of wool color-related genes in Chinese Merino (Junken type) is limited. We employed the Affymetrix microarray to identify differentially expressed genes. 122 genes were differentially expressed, consisting of 117 upregulated and 5 downregulated genes that were related to black/brown skin. The expression level of the BMP2, BMP4, TYRP1, LEPR, DCT, BMPR1A, and TP45A genes was validated by qRT-PCR, and the results coincided with those of microarray. The expression level of ASIP in the black/brown group was significantly lower than that of the white group, suggesting that this plays a key role in the regulation of wool pigmentation. Some cloned color genes (MITF, MC1R, GPR143, and KIT) showed no significant differences in expression levels between the black/brown- and white-skinned sheep. Functional annotation by using Gene Ontology (GO) showed that the differentially expressed genes enriched specific GO terms, particularly those relating to melanin biosynthesis and metabolic processes. KEGG pathway analysis indicated that the categories of tyrosine metabolism and melanogenesis pathway were enriched with differentially expressed genes. Taken together, the present study has shown that the tyrosine metabolism pathway plays an essential role in regulating wool color. The findings of this study may also be utilized in the elucidation of the molecular mechanisms and relationship between genes and wool color in Chinese Merino (Junken type).

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