Genome Array on Differentially Expressed Genes of Skin Tissue in Cashmere Goat at Early Anagen of Cashmere Growth Cycle Using DNA Microarray

In order to study the molecular mechanism involved in cashmere regeneration, this study investigated the gene expression profile of skin tissue at various stages of the cashmere growth cycle and screen differentially expressed genes at proangen in 10 cashmere goats at 2 years of age using agilent sheep oligo microarray. Significance analysis of microarray (SAM) methods was used to identify the differentially expressed genes, Hierarchical clustering was performed to clarify these genes in association with different cashmere growth stages, and GO (Gene ontology) and the pathway analyses were con-ducted by a free web-based Molecular Annotation System3.0 (MAS 3.0). Approximately 10200 probe sets were detected in skin tissue of 2-yr-old cashmere goat. After SAM analysis of the microarray data, totally 417 genes were shown to be differentially expressed at different cashmere growth stages, and 24 genes are significantly up-regulated (21) or down-regulated (3) at proangen concurrently compared to angen and telogen. Hierarchical clustering analysis clearly distinguished the differentially expressed genes of each stage. GO analysis indicated that these altered genes at proangen were predominantly involved in collagen fibril organization, integrin-mediated signaling pathway, cell-matrix adhesion, cell adhesion, transforming growth factor-β (TGF-β) receptor signaling pathway, regulation of cell growth. Kyoto encyclopedia of genes and genomes (KEGG) analysis showed that the significant pathways involved mainly included focal adhesion and extracellular matrixc (ECM)-receptor interaction. Some important genes involved in these biological processes, such as COL1A1, COL1A2, COL3A1, SPARC, CYR61 and CTGF, were related to tissue remolding and repairing and detected by more than one probe with similar expression trends at different stages of cashmere growth cycle. The different expression of these genes may contribute to understanding the molecular mechanism of cashmere regeneration.