Showing papers by "Rong Zhang published in 2005"

Effect of polymorphism of uncoupling protein 3 gene -55 (C>T) on the resting energy expenditure, total body fat and regional body fat in Chinese.

Abstract: Objective To investigate the relationship of the C to T variant at the -55 site of the promoter region of uncoupling protein 3 gene (UCP3) with the resting energy expenditure and the parameters of body fat in Chinese population. Methods Three hundred Chinese (91 normal weight subjects, 209 overweight/obesity subjects) were genotyped for the UCP3 gene -55(C>T) by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Resting energy expenditure (REE), fat mass (FM), fat free mass (FFM) and the parameters for regional adipose tissue distribution were measured. Results Genotype frequencies of UCP3 gene -55(C>T) were not associated with obesity and different types of obesity. The REE level in normal weight subjects with TT homozygotes was higher than that in those with CT heterozygotes and CC homozygotes (P=0.0200). Similar tendency was also observed in overweight/obesity subjects. The FM/FFM exhibited significant differentce between the overweight/obesity subjects with a TT genotype and those with a CT or CC genotype (P=0.0096). Conclusion The level of difference in REE caused by the polymorphism of promoter region of UCP3 -55(C>T) may play a role in energy metabolism in Chinese. Key words: uncoupling protein 3 gene ; resting energy expenditure ; genetic polymorphism ;

Cloning and functional analysis of melanocortin 4 receptor mutation gene F261S

Abstract: OBJECTIVE To evaluate the function change of the melanocortin 4 receptor (MC4R) protein with mutation of F261S METHODS Human embryonic cells of the HEK293 line were cultured Wild-type genomic DNA and F261S mutation human melanocortin 4 receptor genes from the genomic DNA of aproband of homozygotic F612 mutation were amplified and cloned into a topo-TA eukaryotic expression plasmid vector After the wild-type and F261S mutated proteins were expressed in HEK293 cells, alpha-MSH (10(-11) approximately 10(-5) mmol/L) was added, then the intracellular cAMP was detected with dual luciferase reporter assay system RESULTS When the concentration of alpha-MSH added was 10(-9) approximately 10(-8) mmol/L, the intracellular alpha-MSH concentration of the cells transfected with wild-type MC4R gene was significantly higher than that of the cells transfected with F261S mutation gene (P < 005) When the concentration of alpha-MSH added went to 10(-7) approximately 10(-5) mmol/L, the differences became even more significant (all P < 001) CONCLUSION The novel MC4R mutation F261S undermines the signal transduction It may be the possible reason leading to monogenic mutation obesity in Chinese

A novel mutation of WFS1 gene in Chinese patients with Wolfram syndrome

Abstract: Objective Wolfram syndrome is an autosomal recessive disorder characterized by early-onset diabetes mellitus, diabetes insipidus, optic atrophy and deafness. The aim of this study was to scan the WFS1 gene mutations in a Chinese Wolfram syndrome pedigree. Methods Eight exons and flanking introns of WFS1 gene were screened using PCR-DNA direct sequencing. Effects of the mutation on the structure and function of the WFS1 gene product, Wolframin, were evaluated by bioinformatics. Results A novel mutation, F417del, in the WFS1 gene was identified. The patient was homozygous of this mutation and the consanguineous parents were heterozygous. The mutation causes the lose of a non-polar amino acid , which was located in the transmembrane domain of the protein product. Bioinformatics predicted that the mutation altered the secondary structure of the transmembrane domain and decreased the hydrophobicity of F417del protein. Conclusions This study identified a novel mutation of WFS1 gene and represented the first cause of molecular characterization of Chinese Wolfram syndrome patients.