Monognnic diabetes is often misdiagnosed with type 2 diabetes due to overlapping characteristics. This study aimed to discover novel causative mutations of monogenic diabetes in patients with clinically diagnosed type...Monognnic diabetes is often misdiagnosed with type 2 diabetes due to overlapping characteristics. This study aimed to discover novel causative mutations of monogenic diabetes in patients with clinically diagnosed type 2 diabetes and to explore potential molecular mechanisms. Whole-exome sequencing was performed on 31 individuals clinically diagnosed with type 2 diabetes. One novel heterozygnus mutation (p^la2Thr) in INS was identified. It was further gnnotyped in an additional case-control population (6523 cases and 4635 controls), and this variant was observed in 0.09% of cases. IntraceUular trafficking of insulin proteins was assessed in INSl-E and HEK293T cells, p.Ala2Thr preproinsuUn-GFP was markedly retained in the endoplasmic reticulum (ER) in INS1-E cells. Activation of the PERK-elF2a-ATF4, IREla-XBP1, and ATF6 pathways as well as upregulated ER chaperones were detected in INS1-E cells transfected with the p.Ala2Thr mutant. In conclusion, we identified a causative mutation in IN5 respon- sible for maturity-onset diabetes of the young 10 (MODYIO) in a Chinese population and demonstrated that this mutation affected 13 cell function by inducing ER stress.展开更多
AIM: To map Usher phenotype in a consanguineous Pakistani family and identify disease-associated mutation in a causative gene to establish phenotype-genotype correlation.· METHODS: A consanguineous Pakistani fa...AIM: To map Usher phenotype in a consanguineous Pakistani family and identify disease-associated mutation in a causative gene to establish phenotype-genotype correlation.· METHODS: A consanguineous Pakistani family in which Usher phenotype was segregating as an autosomal recessive trait was ascertained. On the basis of results of clinical investigations of affected members of this family disease was diagnosed as Usher syndrome(USH). To identify the locus responsible for the Usher phenotype in this family, genomic DNA from blood sample of each individual was genotyped using microsatellite Short Tandem Repeat(STR) markers for the known Usher syndrome loci. Then direct sequencing was performed to find out disease associated mutations in the candidate gene.· RESULTS: By genetic linkage analysis, the USH phenotype of this family was mapped to PCDH15 locus on chromosome 10q21.1. Three different point mutations in exon 11 of PCDH15 were identified and one of them,c.1304AC was found to be segregating with the disease phenotype in Pakistani family with Usher phenotype.This, c.1304 A C transversion mutation predicts an amino-acid substitution of aspartic acid with an alanine at residue number 435(p.D435A) of its protein product.Moreover, in silico analysis revealed conservation of aspartic acid at position 435 and predicated this change as pathogenic.·CONCLUSION:Theidentificationofc.1304ACpathogenic mutation in PCDH15 gene and its association with Usher syndrome in a consanguineous Pakistani family is thefirst example of a missense mutation of PCDH15 causing USH1 phenotype. In previous reports, it was hypothesized that severe mutations such as truncated protein of PCDH15 led to the Usher I phenotype and that missense variants are mainly responsible for non-syndromic hearing impairment.展开更多
Based on the 58 years monthly flow data (from 1956 to 2013) editing by Jingle hydrological station of Fen River and Shangjinyou station, data resources are used to analyze the annual and inter-annual changes from spat...Based on the 58 years monthly flow data (from 1956 to 2013) editing by Jingle hydrological station of Fen River and Shangjinyou station, data resources are used to analyze the annual and inter-annual changes from spatial and temporal scale by statistical methods, mainly annual spatial and temporal distribution, trend of inter-annual changes, cycle and mutation changes. The reasons of runoff into reservoir changes are deeply analyzed by annual precipitation data of catchments above Fenhe Reservoir 1956 to 2013 and the land and water reservation methods which are implemented recently. It shows that there is a significant decrease of the inter-annual run-off with main and second cycle periods, 23a and 13a respectively. Furthermore, it exists mutation point between 1970 and 1971 through runoff series. As for further analysis of the causes of Fenhe Reservoir runoff changes, it illustrates that the change of precipitation is the main reason the facilitate runoff changes. Also, the land and water reservation methods which are implemented in upstream of Fenhe Reservoir increase water storage capacity of soil, showing it non-ignorable effect to runoff changes.展开更多
β/γ-Crystallins are predominant structural proteins in the cytoplasm of lens fber cells and share a similar fold composing of four Greek-key motifs divided into two domains. Numerous cataract-causing mutations have ...β/γ-Crystallins are predominant structural proteins in the cytoplasm of lens fber cells and share a similar fold composing of four Greek-key motifs divided into two domains. Numerous cataract-causing mutations have been identified in various β/γ-crystallins, but the mech- anisms underlying cataract caused by most mutations remains uncharacterized. The S228P mutation in βB1- crystallin has been linked to autosomal dominant con- genital nuclear cataract. Here we found that the S228P mutant was prone to aggregate and degrade in both of the human and E. coli cells. The intracellular S228P aggregates could be redissolved by lanosterol. The S228P mutation modified the refolding pathway of βB1- crystallin by affecting the formation of the dimeric intermediate but not the monomeric intermediate. Compared with native βBl-crystallin, the refolded S228P protein had less packed structures, unquenched Trp fluorophores and increased hydrophobic exposure. The refolded S228P protein was prone to aggregate at the physiological temperature and decreased the protective effect of βB1-crystallin on βA3-crystallin. Molecular dynamic simulation studies indicated that the mutation decreased the subunit binding energy and modified the distribution of surface electrostatic potentials. More importantly, the mutation separated two interacting loops in the C-terminal domain, which shielded the hydrophobic core from solvent in native βB1-crystallin. These two interacting loops are highly conserved in both of the N- and C-terminal domains of all β/γ-crys- tallins. We propose that these two interacting loops play an important role in the folding and structural stability of β/γ-crystallin domains by protecting the hydrophobic core from solvent access.展开更多
超过6000种人类疾病是由非同义单核苷酸变异(Non-synonymous single nucleotide variations,nsSNVs)引发的,快速准确地预测nsSNVs的致病性,有助于理解发病原理和设计新药物,也是生物信息领域的重要研究课题之一。该文给出了nsSNVs致病...超过6000种人类疾病是由非同义单核苷酸变异(Non-synonymous single nucleotide variations,nsSNVs)引发的,快速准确地预测nsSNVs的致病性,有助于理解发病原理和设计新药物,也是生物信息领域的重要研究课题之一。该文给出了nsSNVs致病性研究的重要意义与背景知识;总结了国内外研究的主流方法,包括基于突变频率的方法、基于通路的方法、结合基因组和转录信息的方法、基于序列进化保守性的方法、基于序列和结构混合特征的方法以及综合评价类方法,对代表性方法进行了阐述;给出了nsSNVs致病性研究中常用的数据库、特征表示方法以及性能评价指标,多角度地对12种nsSNVs致病性预测方法进行了比较;最后,展望了nsSNVs致病性预测中可能取得突破的若干研究方向。展开更多
文摘Monognnic diabetes is often misdiagnosed with type 2 diabetes due to overlapping characteristics. This study aimed to discover novel causative mutations of monogenic diabetes in patients with clinically diagnosed type 2 diabetes and to explore potential molecular mechanisms. Whole-exome sequencing was performed on 31 individuals clinically diagnosed with type 2 diabetes. One novel heterozygnus mutation (p^la2Thr) in INS was identified. It was further gnnotyped in an additional case-control population (6523 cases and 4635 controls), and this variant was observed in 0.09% of cases. IntraceUular trafficking of insulin proteins was assessed in INSl-E and HEK293T cells, p.Ala2Thr preproinsuUn-GFP was markedly retained in the endoplasmic reticulum (ER) in INS1-E cells. Activation of the PERK-elF2a-ATF4, IREla-XBP1, and ATF6 pathways as well as upregulated ER chaperones were detected in INS1-E cells transfected with the p.Ala2Thr mutant. In conclusion, we identified a causative mutation in IN5 respon- sible for maturity-onset diabetes of the young 10 (MODYIO) in a Chinese population and demonstrated that this mutation affected 13 cell function by inducing ER stress.
基金Supported by the Kohat University of Science and Technology,Kohat,PakistanInstitute of Biomedical and Genetic Engineering,Islamabad,Pakistan
文摘AIM: To map Usher phenotype in a consanguineous Pakistani family and identify disease-associated mutation in a causative gene to establish phenotype-genotype correlation.· METHODS: A consanguineous Pakistani family in which Usher phenotype was segregating as an autosomal recessive trait was ascertained. On the basis of results of clinical investigations of affected members of this family disease was diagnosed as Usher syndrome(USH). To identify the locus responsible for the Usher phenotype in this family, genomic DNA from blood sample of each individual was genotyped using microsatellite Short Tandem Repeat(STR) markers for the known Usher syndrome loci. Then direct sequencing was performed to find out disease associated mutations in the candidate gene.· RESULTS: By genetic linkage analysis, the USH phenotype of this family was mapped to PCDH15 locus on chromosome 10q21.1. Three different point mutations in exon 11 of PCDH15 were identified and one of them,c.1304AC was found to be segregating with the disease phenotype in Pakistani family with Usher phenotype.This, c.1304 A C transversion mutation predicts an amino-acid substitution of aspartic acid with an alanine at residue number 435(p.D435A) of its protein product.Moreover, in silico analysis revealed conservation of aspartic acid at position 435 and predicated this change as pathogenic.·CONCLUSION:Theidentificationofc.1304ACpathogenic mutation in PCDH15 gene and its association with Usher syndrome in a consanguineous Pakistani family is thefirst example of a missense mutation of PCDH15 causing USH1 phenotype. In previous reports, it was hypothesized that severe mutations such as truncated protein of PCDH15 led to the Usher I phenotype and that missense variants are mainly responsible for non-syndromic hearing impairment.
文摘Based on the 58 years monthly flow data (from 1956 to 2013) editing by Jingle hydrological station of Fen River and Shangjinyou station, data resources are used to analyze the annual and inter-annual changes from spatial and temporal scale by statistical methods, mainly annual spatial and temporal distribution, trend of inter-annual changes, cycle and mutation changes. The reasons of runoff into reservoir changes are deeply analyzed by annual precipitation data of catchments above Fenhe Reservoir 1956 to 2013 and the land and water reservation methods which are implemented recently. It shows that there is a significant decrease of the inter-annual run-off with main and second cycle periods, 23a and 13a respectively. Furthermore, it exists mutation point between 1970 and 1971 through runoff series. As for further analysis of the causes of Fenhe Reservoir runoff changes, it illustrates that the change of precipitation is the main reason the facilitate runoff changes. Also, the land and water reservation methods which are implemented in upstream of Fenhe Reservoir increase water storage capacity of soil, showing it non-ignorable effect to runoff changes.
文摘β/γ-Crystallins are predominant structural proteins in the cytoplasm of lens fber cells and share a similar fold composing of four Greek-key motifs divided into two domains. Numerous cataract-causing mutations have been identified in various β/γ-crystallins, but the mech- anisms underlying cataract caused by most mutations remains uncharacterized. The S228P mutation in βB1- crystallin has been linked to autosomal dominant con- genital nuclear cataract. Here we found that the S228P mutant was prone to aggregate and degrade in both of the human and E. coli cells. The intracellular S228P aggregates could be redissolved by lanosterol. The S228P mutation modified the refolding pathway of βB1- crystallin by affecting the formation of the dimeric intermediate but not the monomeric intermediate. Compared with native βBl-crystallin, the refolded S228P protein had less packed structures, unquenched Trp fluorophores and increased hydrophobic exposure. The refolded S228P protein was prone to aggregate at the physiological temperature and decreased the protective effect of βB1-crystallin on βA3-crystallin. Molecular dynamic simulation studies indicated that the mutation decreased the subunit binding energy and modified the distribution of surface electrostatic potentials. More importantly, the mutation separated two interacting loops in the C-terminal domain, which shielded the hydrophobic core from solvent in native βB1-crystallin. These two interacting loops are highly conserved in both of the N- and C-terminal domains of all β/γ-crys- tallins. We propose that these two interacting loops play an important role in the folding and structural stability of β/γ-crystallin domains by protecting the hydrophobic core from solvent access.
文摘超过6000种人类疾病是由非同义单核苷酸变异(Non-synonymous single nucleotide variations,nsSNVs)引发的,快速准确地预测nsSNVs的致病性,有助于理解发病原理和设计新药物,也是生物信息领域的重要研究课题之一。该文给出了nsSNVs致病性研究的重要意义与背景知识;总结了国内外研究的主流方法,包括基于突变频率的方法、基于通路的方法、结合基因组和转录信息的方法、基于序列进化保守性的方法、基于序列和结构混合特征的方法以及综合评价类方法,对代表性方法进行了阐述;给出了nsSNVs致病性研究中常用的数据库、特征表示方法以及性能评价指标,多角度地对12种nsSNVs致病性预测方法进行了比较;最后,展望了nsSNVs致病性预测中可能取得突破的若干研究方向。