The effect of small ubiquitin-like modifier-1 modification on the formation of Lewy body-like inclusions in cytoplasm and apoptosis of HEK293 cell induced by overexpression and mutation of alpha-synuclein / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the effect of small ubiquitin-like modifier (SUMO-1) modification on the formation of Lewy body like inclusions in cytoplasm and apoptosis of HEK293 cell induced by overexpression and mutation of alpha-synuclein.</p><p><b>METHODS</b>cDNA encoding the human alpha-synuclein without the stop codon was cloned into a pGEM T-easy vector. Restriction enzyme mapping and DNA sequencing were performed to analyze the plasmid, which was then subcloned into a pEGFP-N1 vector. The recombinant plasmid alpha-synuclein-pEGFP was transfected into HEK293 cells by lipofectamin method. Inclusions in the cultured cells were identified with HE staining. Apoptosis of the HEK293 cell was measured by Hoechst 33258 staining, MTT and Annexin V-PE flow cytometry.</p><p><b>RESULTS</b>The Lewy-body like inclusions were found in cytoplasm of cultured cells. Hoechst staining showed that the nuclei of cells were enlarged in the wild-type and A53T mutation groups 48 h after transfection, chromatin were accumulated and appeared spot-like. The nucleus stain was equitable in the K96R and K96R-A53T groups. MTT assay showed that the viability of cells transfected with empty plasmid was 96.2%, but it dropped to 53.4% and 56.1% in cells transfected with wild-type alpha-synuclein-pEGFP and A53T mutant group, respectively. The viability was 72.3% and 69.8% in cells transfected with K96R and K96R-A53T, respectively (P<0.05). Forty eight hours after transfection, the apoptosis rate was 3.9% in empty plasmid group, 32.2% and 34.1% in cells transfected with wild-type and mutant alpha-synuclein-pEGFP, 19.4% and 20.3% in the K96R and K96R-A53T transfected cells. There was significant difference between the two groups (P<0.05).</p><p><b>CONCLUSION</b>SUMO-1 modification did not have influence on the Lewy body-like inclusions formation in cytoplasm of HEK293 cell in vitro, but had a toxic effect which could increase the apoptosis induced by wild type overexpression and mutation of alpha-synuclein.</p>

Effect of SUMO-1 on mitochondria subcellular localization of alpha-synuclein and its degradation via ubiquitin-proteasome system / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the effect of sumoylation of alpha-synuclein by SUMO-1 on the mitochondria subcellular localization of alpha-synuclein and its degradation via ubiquitin-proteasome system.</p><p><b>METHODS</b>Primers of wild-type, A53T pathogenic mutant and K96R mutant of human alpha-synuclein were designed to amplify the corresponding cDNAs without stop codon. The cDNAs were cloned into pGEM T-easy vector, analyzed by using enzyme mapping and DNA sequencing, and subcloned into pEGFP-N1 vector. The recombinant plasmids of pEGFP-alpha-synuclein-WT, pEGFP-alpha-synuclein-A53T and pEGFP-alpha-synuclein-K96R were transfected into HEK293 cells by lipofectamine method. The expression of the alpha-synuclein protein was measured by immunofluorescence and confocal microscope. Then mitochondria staining as well as immunofluorescence were utilized to investigate the effect of wild-type, A53T mutant and sumoylation of alpha-synuclein on mitochondria subcellular localization of alpha-synuclein. The effect of sumoylation of alpha-synuclein on its degradation via the ubiquitin-proteasome system in the cells was assayed by Western-blot.</p><p><b>RESULTS</b>The enzyme mapping suggested that the eukaryotic expression plasmids for human wild-type, A53T and K96R mutants of the alpha-synuclein gene were constructed successfully. By immunofluorescence and confocal microscope, it was observed that alpha-synuclein-WT and alpha-synuclein-A53T proteins aggregated in cytoplasm, and alpha-synuclein-K96R protein aggregation was decreased in cytoplasm of cultured cells. The alpha-synuclein proteins of wild-type, A53T and K96R mutants were co-localized with mitochondria. Western-blot analysis revealed that both wild-type and A53T mutant affected the amount of the ubiquitinated proteins.</p><p><b>CONCLUSION</b>Neither overexpression of wild-type and A53T pathogenic mutant alpha-synuclein, nor sumoylation of alpha-synuclein, affected the subcellular localization in the mitochondria. However, overexpression of wild-type and A53T mutant alpha-synuclein affected the amount of the ubiquitinated proteins.</p>

Blockade of the aberrant aggregation of alpha-synuclein in HEK293 cells induced by overexpression of wild-type alpha-synuclein by RNA interference / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To construct specific and effective RNA interference(RNAi) plasmid for alpha-synuclein gene and investigate RNAi blockade of the aberrant aggregation of alpha-synuclein in HEK293 cells induced by overexpression of wild-type alpha-synuclein.</p><p><b>METHODS</b>Hairpin RNAs for four target sites were designed to construct four RNAi plasmids pSYNi-1, pSYNi-2, pSYNi-3 and pSYNi-4, using plasmid pBSHH1 vector under the control of the H1 promoter. Western blot and reverse transcription-PCR(RT-PCR) were performed to screen the most specific and effective RNAi plasmid. After confirming the sequences of the plasmids, they were co-transfected into HEK293 cells with the recombinant plasmids alpha-synuclein-pEGFP by using lipofectamin 2000. The aberrant aggregation of alpha-synuclein was measured by EGFP fluorescence and immunocytochemistry for alpha-synuclein. The inclusions in the cultured cells were identified with HE staining.</p><p><b>RESULTS</b>By Western blot and RT-PCR, pSYNi-1 showed the most effective RNAi gene silencing effect (69.6%). After transfecting the RNAi plasmid, the aberrant aggregation of alpha-synuclein in HEK293 cells induced by overexpression of wild-type alpha-synuclein was inhibited. The Lewy body-like inclusions were found in cytoplasm of cultured cells in control group, but disappeared in HEK293 cells cotransfected by pSYNi-1 and alpha-synuclein-pEGFP plasmid.</p><p><b>CONCLUSION</b>RNAi can block the aberrant aggregation and Lewy body-like inclusion formation in cytoplasm of HEK293 cell induced by overexpression of wild-type alpha-synuclein.</p>

The wild-type alpha-synuclein over-expression to induce the protein aberrant aggregation of alpha-synuclein in HEK293 cells in vitro / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate over-expression of wild-type alpha-synuclein inducing the aberrant aggregation of alpha-synuclein in HEK293 cell in vitro.</p><p><b>METHODS</b>The cDNA encoding the human alpha-synuclein without the stop code was cloned into PGEM T-easy vector. Using enzyme map and DNA sequencing analyzed and determined the recombinant plasmid, and then sub-clone the alpha-synuclein cDNA fragment into pEGFP-N1 vector. The recombinant plasmids alpha-synuclein-pEGFP were transfected into HEK293 cells by lipofectamin 2000. The aberrant aggregation of alpha-synuclein was measured by EGFP fluorescence, anti-alpha-synuclein immunocytochemistry. The inclusions in the cultured cells were identified with HE staining.</p><p><b>RESULTS</b>The restriction enzyme map suggested that eukaryotic expression vector for human wild-type alpha-synuclein gene was constructed successfully. By EGFP fluorescence, anti-alpha-synuclein immunocytochemistry, it could be observed that the alpha-synuclein protein could aggregate in cytoplasm and the Lewy body-like inclusions found in cytoplasm of cultured cells.</p><p><b>CONCLUSION</b>The over-expression of wild-type alpha-synuclein can induce protein aberrant aggregation and Lewy body-like inclusions formation in cytoplasm of HEK293 cell in vitro.</p>

A related analysis for alpha, beta fibrinogen gene haplotypes and nucleotide polymorphisms associated with the ischemic stroke in Hainan Han population / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To analyze the association of that the polymorphisms and haplotypes of Taq I site in beta fibrinogen gene and the single nucleotide sites -455 G/A, -249 C/T, -148 C/T, +1689T/G, Bsm A I G/C, 448 G/A, Bcl I G/A, Hinf I A/C in beta-fibrinogen gene are linked up with the ischemic stroke(IS).</p><p><b>METHODS</b>Turbidmetric assay was used to measure the plasma fibrinogen level of one hundred and sixty cases with ischemic stroke and one hundred and thirty healthy individuals from Hainanese Han population. The polymorphisms and genotypes were characterized by PCR-RFLP. Hardy-Weinberg equilibrium and statistical differences of allelic, genotype and haplotype frequencies were obtained by Chi-square test. Pairwise linkage disequilibrium was calculated and haplotypes of nine or four polymorphisms were estimated by the EH + program.</p><p><b>RESULTS</b>There were highly significant differences in genotype frequencies and allelic frequencies of the polymorphisms -455 G/A, -148 C/T, 448 G/A, which happened between the IS group and control subjects (P< 0.01). However, the significant differences of the allelic frequencies in the other six polymorphisms were not found between the IS group and the control (P> 0.05). The odds ratio(OR) with the rare alleles of A -455, T -148 and A 448 is 2.46, 2.30 and 2.08 (95% confidence interval 1.153%-3.924%, 1.429%-3.694% and 1.298%-3.329%) respectively. No definite haplotype block was found by linkage disequilibrium analysis in the control group and the IS group. Association of haplotypes constructed from the nine polymorphisms with IS was not found. Among the haplotypes constructed from four polymorphisms including -455 G/A, -148 C/T, 448 G/A alleles, haplotype differences were found between the control group and the IS group. Haplotypes with G -455, C -148, G448 alleles appeared more frequently in control group(P< or = 0.01), whereas haplotypes with A -455, T -148, A 448 occurred more frequently in the IS group(P< 0.01).</p><p><b>CONCLUSION</b>The results of multi-allele and haplotype analysis indicated that the polymorphisms -455 G/A, -148 C/T, 448 G/A in beta fibrinogen gene were the possible risk factors associated with the occurrence of ischemic stroke in Hainan Han population.</p>

Clinical application of diffusion tensor imaging in cognitive impairment of patients with acute cerebral infarction / 中华神经科杂志

Objective To evaluate the value of diffusion tensor imaging(DTI)in cognitive impairment of patients with acute cerebral infarction.Methods Diffusion tensor images were obtained from 30 volunteers who underwent clinical MR imaging and were found to have no abnormalities on conventional MR images and 30 patients who were clinically diagnosed cerebral infarction and were found to have infarction lesions on conventional MR images.Color-coded FA images and three-dimensional color-coded tensor images were reconstructed.For volunteers,average apparent diffusion coefficient(ADC)and fractional anisotropy(FA)were measured in some main white matter structures of peripheral white matter, basal ganglia,and cerebral peduncle,etc.For infarction patients,ADC and FA were measured and compared between infarction lesions and corresponding contralateral normal regions.Pearson correlation analysis was used to determine correlation with cognitive impairment.Results In infarction patients group, FA and ADC of lesions unrecovered declined.Change in ADC and FA had positive correlation with cognitive impairment of patients with acute cerebral infarction.Conclusion DTI has positive correlation with cognitive impairment of patients with acute cerebral infarction.

RESEARCH ADVANCES ON PSEUDORABIES NEW-TYPE VACCINES / 微生物学通报

Pseudorabies is an important infectious disease for many kinds of livestock and wild animals, and causes important economics losses for pig industry. Many kinds of vaccines including attenuated live viruses or inactivated are widely used for vaccination of pigs and other animals. In the present review, research advances on pseudorabies new-type vaccines such as subunit vaccine, DNA vaccine, recombination vaccine, deletion-mutant vaccine is presented and point out the further development of the vaccine.