Keratin Gene Expression Differences in Wool Follicles and Sequence Diversity of High Glycine-Tyrosine Keratin-Associated Proteins (Kaps) in Magra Sheep of India

Wool fibers consist of proteins with majority belongs to keratin family. Longitudinally arrayed keratin intermediate filaments constitute a matrix surrounded by keratin-associated proteins (KAPs). These KAPs play essential role in providing the physico-mechanical properties of the wool fiber. Real time PCR assay revealed that type 1 hair cortex keratin K33A (K1.2) was significantly (p <= 0.05) upregulated in lustrous Magra wool follicles however other keratin and keratin associated protein (KAP) genes were found down regulated. Furthermore, nucleotide sequence analysis revealed 4, 30, and 7 single nucleotide polymorphisms (SNPs) in KAP6, KAP7, and KAP8 genes, respectively. The presence of differing amount of type I and type II keratin and hydrophobic high glycine-tyrosine proteins in wool might be partially responsible for different glass transitions exhibited by wool and consequently imparts different physical properties like wool luster.