Resistance of Castanea mollissima Shuhe-WYL strain to Dryocosmus kuriphilus and its molecular mechanism.

The resistance of Castanea mollissima Shuhe-WYL strain to Dryocosmus kuriphilus and its molecular mechanism were examined. The larvae of D. kuriphilus were inoculated on the Shuhe-WYL and Qingzha strains, and mortality was observed and compared; the relative mRNA content of the OsCDPK2, receptor-like protein, OsNAC6 protein, KH domain protein, RNA-binding protein, and the bHLH genes was detected using real-time polymerase chain reaction, and then compared between the Shuhe-WYL and Qingzha strains. Phenylalanine ammonia-lyase content was detected by western blotting and compared between the inoculated Shuhe-WYL, non-inoculated Shuhe-WYL, and inoculated Qingzha strains. The mortalities of larvae inoculated on the bud, bracteal leaf, and cardiac lobe were lower in Shuhe-WYL than Qingzha at 48 and 96 h after inoculation; the contents of OsCDPK2, receptor-like protein, OsNAC6 protein, and bHLH in the cardiac lobe were higher in Shuhe-WYL than in Qingzha at 96 h after inoculation, but KH domain protein and RNA-binding protein were not significantly different. The content of phenylalanine ammonia-lyase in the cardiac lobe was higher in inoculated and non-inoculated Shuhe-WYL compared to inoculated Qingzha at 15, 30, 45, and 60 days, and higher in inoculated Shuhe-WYL than in non-inoculated Shuhe-WYL at 15, 30, 45, and 60 days. The content of phenylalanine ammonia-lyase in the cardiac lobe of inoculated Shuhe-WYL had no significant difference between at 60 and at 45 days; and was higher at 60 and 45 days than at 30 and 15 days; and was higher at 30 days than at 15 days (60≈45˃30˃15 days). The C. mollissima Shuhe-WYL strain was resistant to D. kuriphilus; high expression of OsCDPK2, receptor-like protein, OsNAC6 protein, and bHLH and phenylalanine ammonia-lyase may explain the mechanism.

Analysis of the association between polymorphisms in the vitamin D receptor (VDR) gene and dental caries in a Chinese population.

Environmental influences on the development and progression of dental caries are well known; however, there is little evidence of a genetic component imparting susceptibility to dental caries. The aim of this study was to investigate the relationship between a single nucleotide polymorphism in the vitamin D receptor TaqI locus and dental caries susceptibility in a Chinese population. This case-control study was conducted with a case group (264 patients with dental caries from northwestern China) and a control group (219 individuals without dental caries or systemic disease from the same area). DNA was extracted from the peripheral venous blood of the study participants; the distribution of TaqI locus genotypes and allele frequencies was determined via polymerase chain reaction-restriction fragment length polymorphism. The data obtained were statistically analyzed using the Hardy-Weinberg equilibrium and Chi-square test. The frequency of the Tt genotype in the case group (14.0%) was significantly higher than that in the control group (4.3%), as determined using the genotype TT as the reference. The risk of dental caries was increased 3.8-fold in individuals with the heterozygous Tt genotype compared to that in the individuals with the TT genotype. The proportion of the 't' allele in the case group (7.0%) and the control group (2.1%) was observed to be significantly different [P = 0.0003; OR = 3.592, confidence interval 95% (1.790-7.208)]. Our results therefore suggested that the allele 't' might be a genetic factor determining dental caries susceptibility in individuals from the northwest of China.

Genetic polymorphisms in the carbonic anhydrase VI gene and dental caries susceptibility.

We investigated the role of 7 single nucleotide polymorphisms in the carbonic anhydrase (CA) VI gene (rs2274328, rs17032907, rs11576766, rs2274333, rs10864376, rs3765964, and rs6680186) and the possible association between these polymorphisms and dental caries susceptibility in a Northwestern Chinese population. We collected samples from 164 high caries experience and 191 very low caries experience and conducted a case-control study according to the number of decayed, missing, and filled teeth index and genotyped the 7 polymorphisms using a 384-well plate format with the Sequenom MassARRAY platform. Individuals carrying the rs17032907 TT genotype were more likely to have an increased risk of dental caries compared with carriers of the C/C genotype in the co-dominant model, with an odds ratio (95% confidence interval) of 2.144 (1.096-4.195). We also found that the haplotype (ACA) (rs2274328, rs17032907 and rs11576766) was associated with a low number of decayed, missing, and filled teeth index with an odds ratio (95% confidence interval) of 0.635 (0.440-0.918). However, we found no association between dental caries susceptibility and the rs2274328, rs11576766, rs2274333, rs10864376, rs3765964, and rs6680186 polymorphisms and other haplotypes. The rs17032907 genetic variant and the haplotype (ACA) of CA VI may be associated with dental caries susceptibility.