Keratin-associated proteins 9.2 (KAP9.2) gene encodes one of the ultra high sulfur KAPs. Variation in KAP genes may affect the structure of KAPs and hence cashmere characteristics. In order to test the association between the polymorphism of KAP9.2 gene and cashmere trait, DNA sequencing was used to detect a novel C/T polymorphism of KAP9.2 gene from a genomic DNA pool. The mutation could be recognized by Pst I restriction enzyme. To Shanbei white cashmere goat, Inner Mongolia white cashmere goat and Guanzhong dairy goat, the genotypic frequencies of TT, TC and CC from total 1,236 animals were as follows: 0.047, 0.519 and 0.434; 0.180, 0.592 and 0.228; 0.431, 0.544 and 0.025. The allelic frequencies of T and C were 0.307 and 0.693; 0.476 and 0.524; 0.703 and 0.297, respectively, in breeds mentioned above. The frequency of C allele between cashmere and dairy goat was significant (P < 0.01). To provide support for the hypothesis that SNP 586 was responsible for KAP9.2 expression, quantitative real-time PCR analysis revealed that the expression level of KAP9.2 was reduced in individuals bearing genotype CC compared with TT individuals, suggesting that C was the nucleotide causing decreased expression of KAP9.2 or was in linkage disequilibrium with the causative SNP. The 586C/T SNP found in this study might control translation or stability of KAP9.2 mRNA, which would be beneficial for marker assistant selection in cashmere goat breeding.

The 2-DE/MS-based proteomics approach was used to investigate the differences of porcine skeletal muscle, and ATP5B was identified as one differential expression protein. In the present study, ATP5B gene was further cloned by RT-PCR, the sequence was analyzed using the bioinformatics method, and the mRNA expression was detected by qRT-PCR. Sequence analysis showed that the porcine ATP5B gene contains an ORF encoding 528-amino-acid residues with 49 and 166 nucleotides in the 5' and 3' UTRs, respectively. The mRNA of ATP5B was widely expressed in all 14 tissues tested, but especially highly expressed in parorchis and fat. The expression pattern of ATP5B was similar in Large White and Meishan breeds, showing that the expression was upregulated by 3 days after birth and downregulated during postnatal development of skeletal muscle. Comparing the two breeds, the mRNA abundance of ATP5B in Large White was more highly expressed than in Meishan at all developmental stages (P < 0.05). Moreover, a synonymous mutation, G75A in exon 8, was identified and association analysis with the traits of meat quality showed that it was significantly associated with the RLF, FMP, IFR, IMF, and IMW (P < 0.05). These results suggested that ATP5B probably plays a key role in porcine skeletal muscle development and may provide further insight into the molecular mechanisms responsible for breed-specific differences in meat quality.

BackgroundMale germline stem cells (MGSCs) are a subpopulation of germ cells in the testis tissue. MGSCs are capable of differentiation into spermatozoa and thus are perfect targets for genomic manipulation to generate transgenic animals.MethodThe present study was to optimize a protocol of production of transgenic mice through transduction of MGSCs in vivo using lentiviral-based vectors. The recombinant lentiviral vectors with either EF-1 or CMV promoter to drive the expression of enhanced green fluorescent protein (eGFP) transgene were injected into seminiferous tubules or inter-tubular space of 7-day-old and 28-day-old mouse testes. At 5 or 6 wk post-surgery, these pre-founders were mated with wild-type C57BL/6J female mice (1.5 to 2.0-month-old).ResultsSixty-seven percent of F1 generation and 55.56 % of F2 offspring were positive for eGFP transgene under the control of EF-1 promoter via PCR analysis. The transgenic pups were generated in an injection site-and age-independent manner. The expression of transgene was displayed in the progeny derived from lentiviral vector containing CMV promoter to drive transgene, but it was silenced or undetectable in the offspring derived from lentiviral vector with transgene under EF-1 promoter. The methylation level of gDNA in the promoter region of transgene was much higher in the samples derived lentiviral vectors with EF-1 promoter than that with CMV promoter, suggesting eGFP transgene was suppressed by DNA methylation in vivo.ConclusionThis research reported here an effective strategy for generation of transgenic mice through transduction of MGSCs in vivo using lentivirus vectors with specific promoters, and the transgenic offspring were obtained in an injection site-and age-independent manner. This protocol could be applied to other animal species, leading to advancement of animal transgenesis in agricultural and biomedical fields.Electronic supplementary materialThe online version of this article (doi:10.1186/s40104-015-0058-4) contains supplementary material, which is available to authorized users.