Search

To identify protein-protein interaction partners of PER1 (period circadian protein homolog 1), key component of the molecular oscillation system of the circadian rhythm in tumors using bacterial two-hybrid system technique.Human cervical carcinoma cell Hela library was adopted. Recombinant bait plasmid pBT-PER1 and pTRG cDNA plasmid library were cotransformed into the two-hybrid system reporter strain cultured in a special selective medium. Target clones were screened. After isolating the positive clones, the target clones were sequenced and analyzed.Fourteen protein coding genes were identified, 4 of which were found to contain whole coding regions of genes, which included optic atrophy 3 protein (OPA3) associated with mitochondrial dynamics and homo sapiens cutA divalent cation tolerance homolog of E. coli (CUTA) associated with copper metabolism. There were also cellular events related proteins and proteins which are involved in biochemical reaction and signal transduction-related proteins.Identification of potential interacting proteins with PER1 in tumors may provide us new insights into the functions of the circadian clock protein PER1 during tumorigenesis.

Male infertility is one of the major diseases that affect human health and social life, and is influenced by many genetic and environmental factors. Epigenetic modification on DNA strands in response to environmental factors plays an important role in the process of spermatogenesis. Abnormalities of epigenetic regulation may affect both the quantity and quality of sperm production and result in disorders of male reproduction. We hereby review recent progress made in research on epigenetic regulation including DNA methylation, histone modification and non-coding RNA related with male infertility.

To standardize the experimental procedure of the gene test for autosomal dominant cerebellar ataxias (ADCA), and provide the basis for quantitative criteria of the dynamic mutation of spinocerebellar ataxia (SCA) genes in Chinese population.Genotyping of the dynamic mutation loci of the SCA1, SCA2, SCA3, SCA6 and SCA7 genes was performed, using florescence PCR-capillary electrophoresis followed by DNA sequencing, to investigate the variation range of copy number of CAG tandem repeat of the genes in 263 probands of ADCA pedigrees and 261 non-related normal controls. Based on the sequencing result, the bias of the CAG copy number estimation using capillary electrophoresis with different DNA controls was compared to analyze the technical detailes of the electrophresis method in testing the dynamic mutation sites.PCR products containing dynamic mutation loci of the SCA genes showed significantly higher mobility than that of molecular weigh marker with relatively balanced GC content. This was particularly obvious in the SCA2, SCA 6 and SCA7 genes whereas the deviation of copy number could be corrected to +/-1 when known CAG copy number fragments were used as controls. The mobility of PCR products was primarily related to the copy number of CAG repeat when the fragments contained normal CAG repeat. In the 263 ADCA pedigrees, 6 (2.28%) carried SCA1 gene mutation, 8 (3.04%) had SCA2 mutation and 81 (30.80%) harbored SCA3 mutation. The gene mutation of SCA6 and SCA7 was not found. The normal variation range of the CAG repeat was 17-36 copies in SCA1 gene, 13-30 copies in SCA2, 14-39 copies in SCA3, 6-16 copies in SCA6 and 6-13 copies in SCA7. The heterozygosity was 76.1%, 17.7%, 74.4%, 72.1% and 41.3%, respectively. The mutation range of the CAG repeat was 49-56 copies in SCA1 gene, 36-41 copies in SCA2, 59-81 copies in SCA3. Neither homozygous mutation of an SCA gene nor double heterozygous mutation of the SCA genes was observed in the study.The copy number of the CAG repeat in SCA genes could be calculated accurately based on the result of florescence PCR-capillary electrophoresis when limited amount of known repeat copy number controls were used. Our result supported that the notion that SCA3 gene mutation was the most common cause for ADCA, and the obtained data would be helpful for establishing quantitative criteria of the dynamic mutation of the SCA genes in Chinese.

Alpha-2 macroglobulin (alpha2M) is a proteinase inhibitor found in association with senile plaques in Alzheimer's disease (AD). Also alpha2M has been implicated in several pathophysiological processes in AD. In view of the recent contradictory reports on the relationship between AD and a common polymorphism I1000V in A2M gene, the present authors studied a relatively large sample, determined the genotype of the I1000V polymorphism in A2M gene in sporadic AD patients and age-matched controls with normal cognition, and examined the possible association of the polymorphism with AD.Genotypes of A2M and apolipoprotein E (apoE) were detected by polymerase chain reaction combined with restriction fragment length polymorphism in 257 patients and 242 controls in Guangzhou, and 112 patients and 113 controls in Chengdu.The 1000Val allele frequencies in the merged AD and control groups were 7.7% and 8.7%, respectively. The differences of allelic and genotypic frequencies between the patients and control subjects were not statistically significant, even after stratification by apoE epsilon4 status or by age-of-onset of the disease.The results of this study revealed no association between the I1000V polymorphism of A2M and Chinese sporadic AD in Guangzhou and Chengdu.

To analyze the pattern and prevalence of partial copy deletion of deleted-in-azoospermia (DAZ) gene in the azoospermia factor C(AZFc) region of patients with idiopathic azoospermia or severe oligozoospermia.sY581 and sY587 in DAZ gene region were analyzed by polymerase chain reaction-restriction length polymorphism(PCR-RFLP) for its deletion in 197 patients with azoospermia, 166 patients with severe oligozoospermia, and 210 fertile men as controls.Deletion of both DAZ1 and DAZ2 was detected in 18 patients with azoospermia and 10 with severe oligozoospermia, and the prevalence was 9.1% and 6.0% respectively. There was significant difference in deletion rate between the cases and controls.The frequency of partial copy deletion of DAZ gene in Chinese idiopathic azoospermia or severe oligozoospermia patients is much higher than that of fertile controls, suggesting that the deletion of DAZ1/DAZ2 may be one of the important genetic etiological factors of spermatogenesis damage. The pattern and prevalence of DAZ partial copy deletion are similar to those of Caucasians populations, and detection of DAZ gene partial copy deletion by PCR-RFLP may be adopted as an additional clinical gene diagnostic measure after AZF microdeletion detection.

To examine the distribution of 3 polymorphisms of lecithin cholesterol acyltransferase gene in Chinese population and the association of these polymorphisms with lipid metabolism in patients with atherosclerotic heart disease (CHD).Genotypes and frequencies of 3 sites were examined by PCR-restriction fragment length polymorphism technique in 209 unrelated normal control individuals and 203 CHD patients.The observed allele frequencies conform well to Hardy-Weinberg equilibrium. The frequency of 608T allele was significantly higher in controls than that in patients (P=0.034). Compared with the CHD patients without 608T, the CHD patients with 608T exhibited a significant increase in plasma HDL-C concentration (P=0.015). 911T/C and 1188C/T polymorphisms were not found in either group.608T polymorphism of LCAT gene was associated with higher plasma HDL-C level in CHD patients, while 911T/C and 1188C/T polymorphisms maybe very rare in Chinese population.

Both fertilization promoting peptide and adenosine stimulate capacitation but inhibit spontaneous acrosome loss by modulation of the adenylyl cyclase (AC)/cAMP signal transduction pathway. This is a review aimed at analyzing the function of fertilization promoting peptide during this process. The possible molecular basis is also discussed.

To investigate the relationship between the polymorphism of angiotensinogen gene (AGT) and the risk for hypertension in a Chinese population.Three polymorphisms of AGT gene were analyzed in 335 patients with documented essential hypertension and 196 control subjects by using PCR-restriction fragment length polymorphism. Expectation maximization(EM) algorithm was then used for pairwise linkage disequilibrium test and haplotype analysis of AGT polymorphisms.Linkage disequilibrium between M235T and A-20C, between M235T and A-6G, between A-20C and A-6G was observed (P10(-4)). The case-control analysis revealed that the frequency of T235 is significantly higher in essential hypertension patients than in control subjects. But all haplotype frequencies showed no significant difference between the patient and control groups.No association was noted between the haplotypes of AGT gene and hypertension in tested people, but T235 allele might play an important role in increased risk for essential hypertension.

To develop a simple and reliable method for intensifying the hybridization signals of gene chips.The authors added EDTA and another FAM-labeled probe to the normal PCR products, denatured the mixture by heat, and then let the mixture hybridize with the fastened probes on the chip.With the use of EDTA and another FAM-labeled probe, the hybridization signals increased by 6 times or greater.Adding EDTA and another probe to the normal PCR products is a simple and efficient method to intensify the hybridization signal of chips.

To investigate the relationship between major histocompatibility complex class I chain-related A(MICA) gene and systemic lupus erythematosus (SLE).The alleles and frequencies of exons 4 and 5 of MICA gene were determined in 70 cases of SLE and 152 controls of Yunnan Hans by STR genotyping, polymerase chain reaction, single strand conformation polymorphism and bidirection DNA sequencing.Five alleles of exon 5 and 10 alleles of exon 4 were found in this study. The frequency of each allele was determined in patients and controls. There was no significant difference between the two groups in exons 4 and 5 of MICA gene.Exons 4 and 5 of MICA were not related to SLE in Yunnan Hans.

To establish a new nucleic acid hybridization detection technique which may be used in medical genechips.The specific DNA fragment was detected by sequential two hybridization of fluorescence probe with template DNA and fixed DNA probe.Fluorescence probe two-hybridization (FPTH) was applied to genechips for the detection of sex-transmitted pathogens from culture strains, and the results showed that the values of fluorescence density of the positive groups decreased remarkably when compared with those of the negative group. Both the sensitivity and specificity for detecting clinical samples are higher than 90%. There is no need of any additional reagent in hybridization procedure, and the hybridization detection can be accomplished in 40 minutes.The FPTH technique is rapid, simple and reliable, it can also make the clinical detection process completely automatic and integrative.

To investigate the polymorphisms of four microsatellites, D4S1534, D4S1563, D4S423 and D4S414, which are tightly linked to polycystic kidney disease 2 (PKD2) gene, and hence to provide a basis for studying the heterogeneity of adult polycystic kidney disease (APKD).An analysis on the DNA of some unrelated Chinese people was performed using polymerase chain reaction (PCR), polyacrylamide gel electrophoresis (PAGE) and silver staining.In Chinese Hans, there are 11 alleles of D4S1534, and their sizes are 142-162 bp 14 alleles of D4S1563, 205-235 bp 17 alleles of D4S423, 103-135 bp; and 15 alleles of D4S414, 236-264 bp. The polymorphism information contents of the four microsatellites are 0.872, 0.844, 0.921 and 0.871 respectively.In the Chinese Han people studied above, the four microsatellite markers that have many alleles are highly polymorphic genetic markers and may serve as the data of population genetics, suggesting that all four microsatellites could be used in studies on heterogeneity of APKD, linkage analysis of APKD and forensic personal identification.