Analysis of common pathogenic gene mutations of arrhythmogenic right ventricular cardiomyopathy in Yunnan unexplained sudden death cases / 中华地方病学杂志

Objective:To analyze common pathogenic gene mutations of arrhythmogenic right ventricular cardiomyopathy (ARVC) in Yunnan unexplained sudden death (hereinafter referred to as Yunnan sudden death) cases, and explore the etiological relationship between Yunnan sudden death and ARVC.Methods:Four typical Yunnan sudden death affected counties (cities) were selected as investigation sites. Cryopreserved autopsy cardiac cavity blood samples were collected from Yunnan sudden death cases ( n = 3), and peripheral venous blood samples were harvested from their relatives (first, second, third and immediate degree of kinship, n = 67) and control population ( n = 49). The DNA of blood samples was extracted for amplification and sequencing of 97 exons of 5 common ARVC desmosomal protein [desmoplakin (DSP), desmocollin-2 (DSC2), desmoglein-2 (DSG2), plakophilin-2 (PKP2) and junction plakoglobin (JUP)] genes, and genetic lineage of Yunnan sudden death cases was investigated. Results:A total of 17 gene mutation sites were discovered in Yunnan sudden death cases and their relatives, with 6, 5, 4, 1 and 1 in the DSP, DSC2, DSG2, PKP2 and JUP genes, which were not found in the control population. Among them, 9 were newly discovered mutation sites and 8 were reported mutation sites. The DSP gene exon 24 c.8472 G>C, a pure contractual sense mutation, was common in the relatives of 4 cases in the same family surveyed; and one immediate relative carried a deletion mutation at c.2368 - 2370 of exon 15 of DSC2 gene.Conclusion:Yunnan sudden death cases and their relatives carry mutations in the ARVC desmosomal protein DSP, DSC2, DSG2, PKP2, and JUP genes, and the onset of some Yunnan sudden death may be associated with mutations in the ARVC desmosomal protein genes.

Screening of ARVC desmosomal protein gene mutation in Yunnan unexplained sudden death area of a key county, Yunnan / 中华地方病学杂志

Objective:To explore the relationship between arrhythmogenic right ventricular cardiomyopathy (ARVC) desmosomal protein gene mutations and Yunnan unexplained sudden death (hereinafter referred to as Yunnan sudden death) by detecting 5 common ARVC desmosomal protein gene mutations of Yunnan sudden death cases and their relatives in Heqing County, Yunnan Province.Methods:In January 2021, the autopsy heart cavity blood was collected from Yunnan sudden death cases in 8 villages in Heqing County, and peripheral venous blood samples of relatives of the cases were collected. Blood samples' DNA was extracted, after PCR amplification, 97 exons of 5 desmosomal protein genes [desmoplakin (DSP), desmoglein-2 (DSG2), plakophilin-2 (PKP2), junction plakoglobin (JUP) and desmocollin-2 (DSC2)] were sequenced by Sanger method to analyze gene mutations.Results:Three blood samples of Yunnan sudden death cases and 36 blood samples of relatives were collected. A total of 26 gene mutation sites were detected in 39 blood samples, with a total mutation rate of 26.80% (26/97). There were 13, 5, 3, 3 and 2 mutation sites in DSP, DSG2, PKP2, JUP and DSC2 genes, respectively. Among them, 19 were reported mutations and 7 were new mutations: DSP gene exon 3 c.372G>A, exon 15 c.2090A>G, exon 17 c.2371C>A, exon 24-I c.8458T>G; DSG2 gene exon 8 c.861C>T; PKP2 gene exon 3 c.892C>A, exon 8 c.1725G>T. Three Yunnan sudden death cases and 36 relatives were all carriers of compound gene mutation, and the same person carried 3 - 9 gene mutation sites at the same time.Conclusion:Mutations of ARVC desmosomal protein genes DSP, DSG2, PKP2, JUP and DSC2 exist in Yunnan sudden death cases and their relatives, which may be the genetic background factors of some Yunnan sudden death.

Changes in diapause related gene expression pattern during early embryonic development in HCl-treated eggs of bivoltine silkworm Bombyx mori (Lepidoptera: Bombycidae)

Investigation of differential expression of diapause related genes (five metabolic, five heat shock protein and one translational regulatory) in HCl-treated (non-diapause) and untreated (diapause) eggs of B. mori during early embryogenesis (up to 48h following oviposition) revealed the up-regulation of sorbitol dehydrogenase upon HCl treatment, indicating increased glycogen synthesis for further embryonic development but, down-regulation of phosphofructo kinase gene expression after 18h of oviposition indicating an arrest of glycerol and sorbitol conversion. The expression of poly A binding protein gene expression was higher upon HCl treatment, revealing the initiation of translation. The expression levels of other genes analyzed did not vary significantly, except for Hsp90 and Hsp40, which were up-regulated on acid treatment until 18h. Thus, Sorbitoldehydrogenase and phosphofructo kinasegenes have a crucial role in diapause termination as evidenced by HCl treatment, while the other genes did not have major roles.

Convenient genotyping of nine bovine K-casein variants

K-casein gene polymorphisms are of major importance in the dairy industry due to their association with different quality and productive traits (i.e., milk protein). Several methods for genotyping this gene have been proposed; however, none are focused on the simultaneous discrimination of nine K-casein variants. A strategy based on PCR-RFLP was designed to characterize nine K-casein variants (A, B, C, E, F², G, H, I and J) and used to genotype three cattle populations: Gyrholando (3/8 Gyr x 5/8 Holstein), Charolais and Carora. The B variant was the most frequent in the Charolais and Carora breeds, with allelic frequencies of 0.60 and 0.59, respectively. In the Gyrholando breed, four variants were found, with the A variant being the most frequent and E and H the least. The genotyping strategy was effective in detection and differentiation of K-casein variants, and it is proposed for use in laboratories with minimal molecular biology equipment for genotyping and evaluation of the phenotypic effects of nine K-casein variants on milk production and quality.

The significance of methylation status of secreted frizzled-related protein gene promoter in acute leukemia / 中华内科杂志

Objective To investigate the relationship between promoter hypermethylation of secreted frizzled-related protein (SFRP) gene and acute leukemia (AL). Methods We examined the promoter methylation starus of SFRP1, 2, 4 and 5 in primary or relapsed AL patients, cell lines ( HL60,NB4, Molt-4 and Jurkat) and peripheral blood mononuclear cells from healthy people with methylationspecific PCR (MSP). Results None of the normal mononuclear cells showed methylation of any SFRP genes. The frequencies of aberrant methylation among the samples were 33.9% (20/59) for SFRP1,23.7%(14/59) for SFRP2, 6. 8% (4/59) for SFRP4 and 10. 2% (6/59) for SFRP5 in acute myelocytic leukemia (AML), and 39.3% (11/28) for SFRP1, 28.6% (8/28) for SFRP2, 25.0% (7/28) for SFRP4 and 32. 1% (9/28) for SFRP5 in acute lymphoblastic leukemia (ALL). Hypermethylation of SFRP1, 2, 5genes were present in the 4 AL cell lines. SFRP4 was methylated in NB4, Molt-4 and Jurkat cell lines.However, methylation and unmethylation of SFRP4 were both detected in HL60. Conclusions Hypermethylation of SFRP genes is a common event in the evolution of AL. Methylation of SFRP genes might serve as potential independent biomarkers for early detection of AL.

Molecular characterization of 'Candidatus Liberibacter' species/strains causing huanglongbing disease of citrus in Kenya

This study was undertaken to characterize the alpha subgroup of the proteobacteria causing the huanglongbing (HLB) disease of citrus from three different ecological zones of Kenya namely the Lower highlands (LH2, LH3, 1800-1900 m above sea level); Upper midlands (UM3, UM4, 1390-1475m), Lower midlands (LM5, LM4, LM3 of 1290-1340-1390m), by isolation and sequencing DNA encoding the L10 and L12 ribosomal proteins and the intergenic region. A 7I6-basepair DNA fragment was amplified and sequenced and consisted of 536 basepairs of DNA encoding the L10 protein, 44 basepairs of DNA intergenic region and 136 basepairs of DNA that partially encodes the L12 protein. Sequences of rpL10/L12 protein genes from Kenyan strains were 98 percent and 81 percent similar to the South African 'Candidatus Liberibacter africanus strain Nelspruit' and the Asian 'Candidatus Liberibacter asiaticus' strains, respectively. The intergenic rDNA sequence of Kenyan strain from UM and LM showed 84 percent similarity with 'Candidatus L. africanus strain Nelspruit' and 50 percent similarity with 'Candidatus L. asiaticus' strain. However, the LH strain had an 11- basepairs deletion, while the LM4 had a 5-basepair deletion in the intergenic region compared to 'Candidatus L. africanus strain Nelspruit'. The L10 amino acid sequence was 100 percent homologous among HLB bacteria obtained from the agro-ecological zones in Kenya and the L10 protein sequence was also homologus to 'Candidatus L. africanus strain Nelspruit'. Nevertheless, the L10 amino acid sequence of 'Candidatus L. asiaticus' and the 'Candidatus L. africanus subsp. capensis' differed from the Kenyan strains by 18.36 percent and 11.82 percent, respectively. Phylogenetic analysis of both the L10/L12 rDNA sequences and the L10 amino acid sequences clustered the Kenyan strains of the 'Candidatus Liberibacter' species with members of alpha subdivision of proteobacteria.

Aberrant methylation of secreted frizzled-related protein genes in tissues of colorectal cancer and cancer cell lines / 中华消化杂志

Objective To investigate the association of promoter hypermethylation of secreted frizzled-related proteins (SFRPs) in patients with colorectal cancer. Methods The promoter hypermethylation of SFRPs in 20 sporadic colorectal cancer tissues and adjacent mucosa were detected by methylation-specific PCR. The amplified DNA was subcloned into the T-A cloning vector and sequenced. Two colorectal cancer cell lines (HCT116 and SW480) were treated with 5-aza-2' deoxycytidine for demethylation. The promoter hypermethylation and protein expression of SFRPs in colorectal cancer cell lines were detected by methylation-specific PCR and Western blotting. Results It was demonstrated that the hypermethylation of SFRP 1, 2, 4 or 5 was 19/20,17/20,3/20 or 13/20in cancer tissues, respectively, whereas it was 12/20, 8/12, 1/20 or 7/20 in adjacent mucosa,respectively. SFRP 1, 2 or 5 methylation was more frequently found in cancer tissue than in adjacent mucosa (P～0.05). Methylation of SFRP 1, 2, 4 and 5 were found in HCT116 cell line, but only SFRP1 and SFRP2 were found in SW480 cell line. There was a negative correlation between protein expression and methylation of SFRPs. The Western blotting revealed that SFRP protein re-expressedafter it treated with 5-aza-2' deoxyeytidine. Conclusion Methylation of SFRP 1, 2 or 5 gene is associated with the evolution of eolorectal cancer, and is closely related to silencing expression.