ABSTRACT. High glycine-tyrosine proteins (HGTPs), also known as keratin-associated proteins (KAPs), play a key role in the major structures and mechanical properties of wool fiber. Sheep HGTPs consist of three multigene families: KAP6, KAP7, and KAP8 genes. Polymorphisms of these three genes have been proposed to have important effects on wool fiber traits. The aim of the present study was to identify polymorphisms of the KAP6, KAP7, and KAP8 genes in four sheep breeds, including Chinese Merino superfine wool sheep, Hu sheep, a Merino x Hu crossed breed, and Romney sheep. Polymerase chain reaction (PCR) product direct sequencing, PCR-single-strand conformation polymorphism, and cloned sequencing methods were used to find genetic variation and identify polymorphisms in these genes. The Mutation Surveyor v3.97 software was used to analyze the sequences. These methods revealed six different sequences of the KAP6 gene, two different sequences of the KAP7 gene, and five different sequences of the KAP8 gene. Accordingly, 3439©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 13 (2): 3438-3445 (2014) Polymorphisms of sheep wool keratin-associated protein genes three (with frequencies >1%) single nucleotide polymorphisms (SNPs) of the KAP6 gene, one SNP of the KAP7 gene, and five SNPs of the KAP8 gene were detected. Interestingly, some of these sequences were present in only certain sheep breeds, thereby suggesting that these special allele sequences could be used as candidate genes of wool characteristics in further studies.

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Sm-Fe-N was prepared by melt-spun Sm-Fe with liquid-N2-cooled copper wheel and nitrogen absorption under N2 gas pressures up to 25 MPa. The structure and magnetic properties of the Sm-Fe-N prepared under varied temperatures, N2 pressures and nitrogen absorption time have been investigated systematically. The liquid N2 melt-spun process improves the homogeneity of the samples while the high N2 pressure increases the efficiency of the nitrogenation process. The Sm-Fe-N decomposes under 25 MPa N2 at temperatures above 743 K.

To analyze the associations of polymorphisms of prion protein gene (PRNP) with reproduction traits in Chinese Holstein bulls, significant statistical results are found in sperm quality traits between individuals with different 23-bp in-del, 12-bp in-del, and 24-bp in-del polymorphic genotypes. The individuals with 12-bp and 23-bp insertion polymorphisms had lower ejaculation volume, the number of straw frozen sperm once ejaculation and the number of straw per year than that of deletion polymorphisms at this two sites(p < 0.05). The individuals with 24-bp in-in genotype had lower number of straw per year than that of 24-bp in-del genotype (p < 0.050). These results showed the trend that resistant cattle PRNP genotypes possibly had negative effects on production traits in bulls. Therefore, this study provided possible molecular markers for bull breeding in resistance selection.