RESUMEN
We aimed to elucidate the association between connexin 40 (Cx40) genetic polymorphisms and atrial fibrillation (AF) in a Chinese population in Xinjiang comprising Uyghur and Han individuals. We enrolled 275 Uyghur and 305 age- and gender-matched Han subjects, and used polymerase chain reaction to detect single nucleotide polymorphisms (SNPs; -44G/A and +71A/G) in the gene encoding Cx40. A mutation screening was performed by direct sequencing and calculation of genotype and allele frequencies among AF patients and control subjects to determine the relationship between these variants and this condition in Uyghur and Han populations. The two SNPs examined were significantly associated with AF in both ethnic groups. Further analysis showed the SNPs to be in perfect linkage disequilibrium in both AF and control groups among Uyghur and Han individuals. In both populations -44AA genotype and A allele frequencies among AF patients were significantly higher than those in the control group. In addition, under the dominant model (GG vs GA+AA), a significant difference in the distribution of Cx40 -44G/A genotypes was detected between patients and controls. Logistic regression analysis revealed that Cx40 genetic polymorphisms increase AF risk in Uyghur and Han residents of Xinjiang. In conclusion, both the -44G/A and +71A/G variants of the gene encoding this protein are associated with AF in Uyghur and Han populations in northern China.
Asunto(s)
Pueblo Asiatico/genética , Fibrilación Atrial/genética , Conexinas/genética , Etnicidad/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple/genética , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Secuencia de Bases , Estudios de Casos y Controles , China , Electroforesis en Gel de Agar , Femenino , Frecuencia de los Genes/genética , Humanos , Desequilibrio de Ligamiento/genética , Modelos Logísticos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Proteína alfa-5 de Unión ComunicanteRESUMEN
We analyzed the susceptibility of intestinal stromal tumors using cell culture and proteomics. Human SGC7901 gastric cells were selected and divided into a blank control group (untransfected SGC7901 cells), a negative control group [SGC7901 cells transfected with negative interference control-small interfering RNA (siRNA)], and a COOH-terminus tensin-like molecule (CTEN)-siRNA-1 group (SGC7901 cells transfected with CTEN-siRNA-1). The cells were successfully transfected and subjected to analyses of cell proliferation, cell cycle, cell invasion, CTEN expression, and proteomics. The percentages of cells in the G0/G1, S, and G2/M phases were similar in the three groups (P > 0.05), and the OD values were also similar at 24, 48, and 72 h (P > 0.05). Compared with the levels in the blank and negative control groups, CTEN protein in the CTEN-siRNA-1 group decreased by 66 and 65%, respectively, and significantly fewer cells in the CTEN-siRNA-1 group were capable of invasion (P < 0.05). Proteomic analysis showed that in the CTEN-siRNA-1 group, 283 proteins were upregulated and 242 were downregulated; from these, the expression levels of E-cadherin and ERK proteins changed significantly. Silencing the expression of CTEN in intestinal stromal tumor cells reduces their invasion capability. Moreover, silencing CTEN at different stages can also regulate the expression levels of E-cadherin and ERK proteins.
Asunto(s)
Tumores del Estroma Gastrointestinal/metabolismo , Proteómica/métodos , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/genética , Regulación Neoplásica de la Expresión Génica/fisiología , Humanos , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , TensinasRESUMEN
Variation in the chloroplast DNA sequence is useful for plant phylogenetic studies. However, the number of variable sequences provided by chloroplast DNA for suggested genes or genomic regions in plant phylogenetic analyses is often inadequate. To identify conserved regions that can be used to design primers and amplify variable sequences for use in plant phylogenetic studies, the complete chloroplast genomic sequences of six plant species (including Oryza sativa, Arabidopsis thaliana, Glycine max, Lotus japonicus, Medicago truncatula, and Phaseolus vulgaris), searched from the taxonomy database of NCBI were investigated. A total of 93 conserved regions, 32 in large single copy and 61 in inverted repeat regions, were identified. A set of five primer pairs were designed according to the conserved sequences located in the psbA~trnK, psbB~psbH, rpl23~trnI, trnR~trnN, and trnY~trnD regions to amplify variable DNA fragments. An additional 18 plant accessions from 14 species were used to validate their utility. Each of the tested species could be distinguished by length polymorphisms of fragments amplified with the five primer pairs. trnR~trnN and rpl23~trnI amplified fragments specific to monocot and legume species, respectively. Three primer pairs located in the psbA~trnK, psbB~psbH, and trnR~trnN regions were applied to amplify variable DNA sequences for phylogenetic analysis using the maximum parsimony method. The consistent result between taxonomy and phylogenetic analysis on the variable sequences amplified with these three primer pairs was revealed. The five newly developed primer pairs are recommended as tools for use in the identification of plant species and in phylogenetic studies.
Asunto(s)
Cartilla de ADN/genética , ADN de Cloroplastos/genética , Genoma del Cloroplasto , Filogenia , Arabidopsis/genética , Variación Genética , Genoma de Planta , Oryza/genéticaRESUMEN
A few insect control genes of Bacillus thuringiensis have been modified successfully to increase the expression in plants by replacing rare codons, increasing GC content, and avoiding the DNA elements that could cause premature transcription termination, mRNA instability, and potential methylation. However, the modification process was intricate and often confused researchers. In this study, we adopted a simple method to modify Cry1Ab only by individually replacing its amino acid sequence with corresponding rice-preferred codons based on analysis of 92,188 coding DNA sequences. Unexpectedly, all elements of A+T richness, which terminate or destabilize transcription in plants, were avoided in the newly designed mCry1Ab. However, mCry1Ab had 2 notable features: less synonymous codons and high GC content. mCry1Ab only employed 22 of the 61 codons to encode protein and had an enhanced GC content of 65%. The increase in GC content caused abundant potential methylation signals to emerge in mCry1Ab. To test whether mCry1Ab could be expressed in rice, we transferred it into Oryza japonica variety Wanjing97. Insect bioassays revealed that transgenic plants harboring this gene driven by 2 promoters, CaMV35S and OsTSP I, were highly resistant to rice leaffolder (Cnaphalocrocis medinalis). Analysis of R0 to R2 generation plants indicated that the mCry1Ab was inherited stably by the progeny. Our study provided a simple modified method for expressing exogenous genes in rice and confirmed that less synonymous codons and high GC content do not affect transgene expression in rice.
Asunto(s)
Proteínas Bacterianas/genética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Oryza/genética , Control Biológico de Vectores , Plantas Modificadas Genéticamente/genética , Secuencia de Aminoácidos , Animales , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis , Lepidópteros/patogenicidad , Oryza/crecimiento & desarrollo , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Regiones Promotoras GenéticasRESUMEN
The TaqI B polymorphism in the cholesterol ester transfer protein (CETP) (B1 and B2 alleles; rs708272) is associated with changes in enzyme activity and lipid concentrations. The B1 allele of the CETP gene is a known independent risk factor for genetic susceptibility to atrial fibrillation (AF); however, little is known about this polymorphism in the minority groups of Xinjiang, China. We examined the role of this polymorphism in AF using two independent case-control studies: the Han population (101 AF patients and 129 control subjects) and the Kazak population (103 AF patients and 101 control subjects). Carriers of the B1B1 genotype were more frequent among AF patients than among controls both in the Han population (34.7 versus 26.4%; χ(2) = 10.686, P = 0.001) and in the Kazak population (53.4 versus 24.8%; χ(2) = 27.802, P < 0.001). The odds ratio (OR) for carriers of the B1B1 genotype to AF susceptibility was 0.187 [95% confidence interval (CI) = 0.071- 0.491] in the Han group and 8.426 (95%CI = 2.295-30.933) in the Kazak population. After adjustment of confounding factors such as gender, age, smoking, alcohol consumption, hypertension, diabetes, as well as serum levels of triglyceride, total cholesterol, and high-density lipoprotein, the difference remained significant in the Han group (P = 0.001; OR = 0.187, 95%CI = 0.071-0.491) and in the Kazak group (P = 0.001; OR = 8.426, 95%CI = 2.295-30.933). The presence of the B1B1 polymorphism of the Taq1B CETP genotype contributes to the development of AF in the Han and Kazak populations in western China (Xinjiang).