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As a useful tool for genetic engineering, piggyBac (PB) transposons have been widely used in more than one species of transgenosis or generating mutation studies. At present, the studies about PB transposons in cattle were few. In order to get the PB transposon integration sites and summarize its characteristics in bovine genome, donor plasmid of PB[CMV-EGFP] and helper-dependent plasmid of pcDNA-PBase were constructed and transferred into bovine fibroblasts by Amaxa basic nucleofector kit for primary mammalian fibroblasts. Cell clones stably transfected were obtained after screening by G-418. Genomic DNA of transgenic cells was extracted and the integration sites of PB transposon were detected by genome walking technology. Eight integration sites were obtained in bovine genome, although only 5 sites were mapped on chromosomes 1, 2, 11, and X chromosome. We found that PB transposon was inserted into the "TTAA" location and integrated into the intergenic non-regulatory sites between two genes. Analysis of the composition of the five bases, which was close to the side of the PB integration sites "TTAA", showed that PB 5' tended to be inserted into region rich in GC (62.5%). From the study, we got that transposition occurred in cattle genome by PB transposons and the integration site information acquired from the research will provide theoretical references for bovine study by PB transposon.

With the implementation of genetic improvement in recent years, artificial selection has greatly improved beef cattle production performance and its genetic basis has been dramatically changed. In this study, based on the Illumina BovineSNP50 (54K) and BovineHD (770K) BeadChip and the FST value, we analyzed the genetic differentiation of cattle and screened the imprints of selection in bovine genome. Finally, we found 47104 OUTLIER SNP loci and 3064 candidate genes, for example, CLIC5, TG, CACNA2D1, and FSHR etc. The biological processes and molecular functions of genes were analyzed through gene annotation.The results of this study established a genome-wide map of selection footprints in beef cattle genome and a clue for in-depth study of artificial selection and understanding of biological evolution.Our results indicate that artificial selection has played an important role in cattle breed genetic improvement.

Objective: To observe whether Naomai Yihao (NM) Capsule, a compound traditional Chinese herbal medicine for regulating the "sea of blood in brain", and bone marrow stromal stem cell (BMSC) transplantation could improve angiogenesis in focal cerebral ischemia in rats., Methods: A rat model of middle cerebral artery occlusion (MCAO) was established. The rats were divided into untreated group, NM group, BMSC group and combination of NM and BMSC group (combined treatment group). Another 8 normal rats were selected as sham-operated group. After 3-, 7- and 14-day reperfusion, behavioral rating scale (BRS) of the rats and histopathology of the cerebral tissue were evaluated. Expression of CD31 in the brain tissue was also measured by immunohistochemical method., Results: Compared with the untreated group, BRSs of the NM group, BMSC group and combined treatment group were decreased significantly (P=0.000), but there was no interacting effect between NM and BMSC transplantation. Compared with the untreated group, the numbers of CD31 positive cells in NM group, BMSC group and combined treatment group were increased significantly (P=0.000), and there were interacting effects among NM, BMSC transplantation, and the observation time (P<0.01). After 14-day reperfusion, combination of NM and BMSC transplantation could largely increase the number of CD31 positive cells., Conclusion: NM is able to promote the angiogenesis and neurological impairment improvement in focal cerebral ischemia of rats which are administered with BMSC transplantation, and the effect is reinforced with the extension of treatment time.

A 261 bp sequence of the bovine MyoD gene intron 2 was cloned and was found to bear no similarities to the human MyoD gene sequence. Polymorphisms of the Myod gene in cattle including three Chinese breeds (Luxi cattle, Jinnan cattle and Qinchuan cattle) and four cross-breeding populations (Limousin x Luxi cattle, Simmental x Luxi cattle, Charolais x Luxi cattle and Angus x Luxi cattle) were detected by PCR-SSCP. Two SSCP alleles (A and B) were detected, which caused by a C-->T at 39 bp and a C-->G transition at 112 bp. Only two genotypes AA and AB occurred in the population. In Chinese local cattle, B allele was dominant, and this locus was at Hardy-Weinberg equilibrium except for the Charolais x Luxi cattle and Angus x Luxi cattle. The association of these polymorphisms with cattle carcass traits was analyzed using the general linear model (GLM). Statistical analysis revealed a higher value of living weight, carcass weight and loin eye area for individuals with genotype AA than AB (P < 0.05). Further studies on a bigger population size are needed to confirm the observed effect of MyoD genotypes on carcass quality traits.