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971.
972.
Cai L  Han X  Hu D  Li X  Wang B  Ni J  Zhou Z  Yu X  Zhai X  Tian K 《Journal of virology》2012,86(12):7017
Here, we report a novel porcine circovirus type 2a (PCV2a) strain with 11 nucleotides (nt) inserted in the origin of genome replication (Ori). This is the first report of a PCV2a strain with nucleotide insertion in Ori. Our study will help further epidemiological studies and extend our knowledge of evolutionary characteristics of PCV2.  相似文献   
973.
Nine novel human papillomavirus (HPV) types were isolated from healthy skin of individuals in rural Anyang, China. All of these isolates belong to the genus Gammapapillomavirus. These data will provide us with useful information for a better understanding of PV evolution and the relationship of PV with the host.  相似文献   
974.
975.
Younas M  Xiao Y  Cai D  Yang W  Ye W  Wu J  Liu K 《Molecular biology reports》2012,39(5):5105-5113
Evaluation of the genetic diversity in conventional and modern rapeseed cultivars is essential for conservation, management and utilization of these genetic resources for high yielding hybrid production. The objective of this research was to evaluate a collection of 86 oilseed rape cultivars with 188 simple sequence repeat (SSR) markers to assess the genetic variability, heterotic group identity and relationships within and between the groups identified among the genotypes. A total of 631 alleles at 188 SSR markers were detected including 53 and 84 unique and private alleles respectively, which indicated great richness and uniqueness of genetic variation in these selected cultivars. The mean number of alleles per locus was 3.3 and the average polymorphic information content was 0.35 for all microsatellite loci. Unweighted Pair Group Method with Arithmetic Mean clustering and principal component analysis consistently divided all the cultivars into four distinct groups (I, II, III and IV) which largely coincided with their geographical distributions. The Chinese origin cultivars are predominantly assembled in Group II and showed wide genetic base because of its high allelic abundance at SSR loci while most of the exotic cultivars grouped into Group I and were highly distinct owing to the abundant private and unique alleles. The highest genetic distance was found between Group I and IV, which mainly comprised of exotic and newly synthesized yellow seeded (1728-1 and G1087) breeding lines, respectively. Our study provides important insights into further utilization of exotic Brassica napus accessions in Chinese rapeseed breeding and vice versa.  相似文献   
976.
Applying the genomic library construction strategy and colony screening, a new aroA gene encoding 5-enolpyruvylshikimate-3-phosphate synthase has been identified, cloned and overexpressed in Escherichia coli, and the enzyme was purified to homogeneity. Kinetic analysis of the AroA P.fluorescens indicated that the full-length enzyme exhibits 10-fold increased IC50 and an approximately 38-fold increased K i for glyphosate compared to those of the AroA E.coli , while retaining high affinity for the substrate phosphoenolpyruvate. Furthermore, we have transformed the new aroA P.fluorescens gene into Arabidopsis thaliana via a floral dip method, and demonstrated that transgenic A. thaliana plants exhibit significant glyphosate resistance when compared with the wild type.  相似文献   
977.
To select the molecular genetic markers related to egg performance of Wanjiang white goose, prolactin receptor gene (PRLR) was adopted to be a candidate gene in our study. Five pairs of primers (P1–P5) were designed to detect the SNPs of PRLR gene by PCR-SSCP method. The results revealed that polymorphisms were discovered in the PCR products amplified with P4 primers in PRLR exon 10, three genotypes were found: AA, AB and AC. The sequence of AB genotype is the same as original sequence (DQ660982) in NCBI. There are five mutations in AA genotype: C → A at 840 bp, C → T at 862 bp, T → C at 875 bp, T → A at 963 bp, A → T at 989 bp, resulting in amino acid mutations: His → Asn, Thr → Ile, Asn → Lys, Thr → Ser, and synonymous mutation at 875 bp. Sequencing revealed five mutations in AC genotype: G → T at 816 bp, A → T at 861 bp, C → T at 862 bp, T → C at 875 bp, A → G at 948 bp, causing amino acid mutations of Val → Phe, Thr → Phe, synonymous mutations at 875 and 963 bp. Besides, there are an N-glycosylation site (NQSR), three casein kinase II phosphorylation sites including SIIE, SKTE, and SLMD in AA genotype; three casein kinase II phosphorylation sites including SIIE, SKTE, and TLMD in AB genotype; three casein kinase II phosphorylation sites including SIFE, SKTE, and TLMD in AC genotype. The annual egg yielding of AB genotype geese are significantly more than those of AA and AC genotype geese on the average (P < 0.05). It is suggested for the first time that PRLR is a promising candidate gene that can affect egg performance in Wanjiang white goose.  相似文献   
978.
Glucagon-like peptide-1 (GLP-1), a gut incretin hormone secreted from L cells, and a GLP-1 receptor agonist, exendin-4 (Ex-4) has been shown to be cardioprotective and could exert beneficial effects through its anti-inflammatory property. However, the mechanism remains unclear. The purpose of this study was to investigate whether Ex-4 could ameliorate myocardial cell injury by inhibiting high mobility group box 1 (HMGB1) expression under high glucose condition. Neonatal rat ventricular myocytes were prepared and then cultured with high glucose and different concentration of Ex-4. Lactate dehydrogenase (LDH), creatine kinase (CK), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), malondialdehyde (MDA) and superoxide dismutase (SOD) were measured. HMGB1 expression was assessed by western blotting. Ex-4 significantly inhibited the increase in LDH, CK, TNF-α, IL-1β and MDA levels induced by high glucose, especially at the 1 and 10?nM concentrations as well as suppressed the decrease in SOD level. Meanwhile, HMGB1 expression was markedly increased after 12?h of hyperglycaemia (P?<?0.05), which was significantly inhibited by Ex-4, especially at the 1 and 10?nM concentrations (P?<?0.05). The present study suggested that Ex-4 could reduce high glucose-induced cardiocytes injury, which may be associated with the inhibition of HMGB1 expression.  相似文献   
979.
Gap junction provides intercellular communications that play a critical role in invasion of metastatic cancer cells. However, the effects of inhibiting this pathway in breast cancer cell migration have not been investigated. Here, we present data demonstrating that functional blockade of gap junctions during the formation of monolayer decreased the levels of aligned fibers of actin between neighboring breast cancer cells. Furthermore, gap junction inhibitors attenuated the invasion ability of highly metastatic MDA-MB-231 cells, but had no significant effects on less invasive MCF-7 cells, which caused by shRANKL. Our work is the first to demonstrate the inhibitory effect of gap junction channel inhibitors on the migration of highly invasive breast cancer cells.  相似文献   
980.
Yang F  Li L  Liu H  Cai Y  Wang G 《Molecular biology reports》2012,39(4):3957-3964
β-lactoglobulin (β-LG) is the major whey protein in the milk. In order to investigate the polymorphism of β-LG variant B precursor (β-LG B*: GenBank accession no. DQ489319) gene and its effects on the milk traits, the single-strand conformation polymorphism method (PCR-SSCP) were adopted to analyze polymorphism between 5229th and 5476th bp in the β-LG B* gene in Chinese Holstein. Four genotypes were found (AA, AB, AC and ABC) and 3 single nucleotide polymorphisms (SNPs) were detected (g.5239C>A, g.5240A>C, g.5305C>T and mix type g.5305C/T) in the exon 4 of β-LG B* gene. It was also found that the protein contents of AB, AC and ABC dairy cows were higher than AA (P < 0.05), and AC cows were the highest among them. Three SNPs (g.5239C>A, g.5240A>C and g.5305C>T) might affect the milk trait and all of them were high polymorphism (0.5 < PIC < 1.0). In further researches, the three SNPs also caused amino acid change (Asp>Glu, Thr>Pro and Ala>Val) respectively, and the spatial secondary and tertiary structure forecasting result also showed that single amino acid change influence protein spatial structure change in Chinese Holstein. Taken together, it is suggested that these SNPs change β-LG B* gene structure and expression. The polymorphism possibly holds the secret of milk protein and fat contents in the milk of Chinese Holstein.  相似文献   
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