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1.
Genomics ; 107(1): 24-32, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26688439

RESUMO

Familial hypercholesterolemia (FH) is an autosomal dominant disease, predominantly caused by variants in the low-density lipoprotein (LDL) receptor gene (LDLR). Herein, we describe genetic analysis of severely affected homozygous FH patients who were mostly resistant to statin therapy and were managed on an apheresis program. We identified a recurrent frameshift mutation p.(G676Afs*33) in exon 14 of the LDLR gene in 9 probands and their relatives in an apparently unrelated Saudi families. We also describe a three dimensional homology model of the LDL receptor protein (LDLR) structure and examine the consequence of the frameshift mutation p.(G676Afs*33), as this could affect the LDLR structure in a region involved in dimer formation, and protein stability. This finding of a recurrent mutation causing FH in the Saudi population could serve to develop a rapid genetic screening procedure for FH, and the 3D-structure analysis of the mutant LDLR, may provide tools to develop a mechanistic model of the LDLR function.


Assuntos
Mutação da Fase de Leitura , Hiperlipoproteinemia Tipo II/genética , Receptores de LDL/química , Adolescente , Adulto , Sequência de Aminoácidos , Criança , Pré-Escolar , Éxons , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Linhagem , Receptores de LDL/genética
2.
Eur Biophys J ; 44(1-2): 17-26, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25395330

RESUMO

Heat shock protein A6, also known as HSP70B', is a member of the Hsp70 family of molecular chaperones. Under stressed conditions, the level of HSPA6 increases substantially, and the protein has been targeted as a biomarker of cellular stress in several studies. We report the spectroscopic and thermodynamic properties of Arabian camel species cHSPA6, determined by measurement of intrinsic and extrinsic fluorescence emission, and use of far-UV circular dichroism and dynamic multimode spectroscopy. Our results showed that cHSPA6 has similar binding affinity for both ATP and ADP (K D = ~50 nM). Binding of ATP and ADP reduced the surface hydrophobicity of the protein, and slightly altered its secondary structure, suggesting localized conformational rearrangement after ATP or ADP binding. Dynamic multimode spectroscopy revealed that cHSPA6 unfolds through three transitions with melting points (T m) of 42.3 ± 0.2, 61.3 ± 0.1, and 81.2 ± 0.2 °C. To the best of the author's knowledge, and literature search, this is the first report of the spectroscopic and thermodynamic properties of the Arabian camel heat shock protein.


Assuntos
Proteínas de Choque Térmico/química , Simulação de Dinâmica Molecular , Sequência de Aminoácidos , Animais , Camelus , Dados de Sequência Molecular , Proteínas Recombinantes/química
3.
Mar Drugs ; 13(5): 2875-89, 2015 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-26006710

RESUMO

The effect of carrageenans on tomato chlorotic dwarf viroid (TCDVd) replication and symptom expression was studied. Three-week-old tomato plants were spray-treated with iota(É©)-, lambda(λ)-, and kappa(κ)-carrageenan at 1 g·L-1 and inoculated with TCDVd after 48 h. The λ-carrageenan significantly suppressed viroid symptom expression after eight weeks of inoculation, only 28% plants showed distinctive bunchy-top symptoms as compared to the 82% in the control group. Viroid concentration was reduced in the infected shoot cuttings incubated in λ-carrageenan amended growth medium. Proteome analysis revealed that 16 tomato proteins were differentially expressed in the λ-carrageenan treated plants. Jasmonic acid related genes, allene oxide synthase (AOS) and lipoxygenase (LOX), were up-regulated in λ-carrageenan treatment during viroid infection. Taken together, our results suggest that λ-carrageenan induced tomato defense against TCDVd, which was partly jasmonic acid (JA) dependent, and that it could be explored in plant protection against viroid infection.


Assuntos
Carragenina/farmacologia , Replicação do DNA/efeitos dos fármacos , Doenças das Plantas/virologia , Solanum lycopersicum/genética , Solanum lycopersicum/virologia , Viroides/efeitos dos fármacos , Ciclopentanos/metabolismo , Oxirredutases Intramoleculares/genética , Lipoxigenase/genética , Solanum lycopersicum/metabolismo , Oxilipinas/metabolismo , Doenças das Plantas/genética , Proteoma/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Viroides/genética
4.
Mol Genet Genomics ; 289(3): 469-87, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24562863

RESUMO

We screened for the major essential single-nucleotide polymorphism (SNP) variant that might be associated with the MSH2 gene based on the data available from three types of human tissue samples [156 lymphoblastoid cell variations (LCL), 160 epidermis, 166 fat]. An association analysis confirmed that the KCNK12 SNP variant (rs748780) was highly associated (p value 9 × 10(-4)) with the MSH2 gene for all three samples. Using SNP identification, we further found that the recognized SNP was also relevant among Hapmap populations. Techniques that display specific SNPs associated with the gene of interest or nearby genes provide more reliable genetic associations than techniques that rely on data from individual SNPs. We investigated the MSH2 gene regional linkage association with the determined SNP (rs748780), KCNK12 variant (Allele T>C) in the intronic region, in HapMap3 full dataset populations, Yoruba in Ibadan, Nigeria (YRI), Utah residents with ancestry from northern Europe (CEU), Han Chinese in Beijing, China (CHB), and a population of Mexican ancestry in Los Angeles, California (MEX). A gene-based SNP association analysis analyzes the combined impact of every variant within the gene while creating referrals to linkage disequilibrium or connections between markers. Our results indicated that among the four populations studied, this association was highest in the MEX population based on the r(2) value; a similar pattern was also observed in the other three populations. The relevant SNP rs748780 in KCNK12 is related to a superfamily of potassium channel pore-forming P-domain proteins as well as to other non-pore-forming proteins and has been shown to be relevant to neurological disorder predisposition in MEX as well as in other populations.


Assuntos
Reparo de Erro de Pareamento de DNA , Estudos de Associação Genética , Proteína 2 Homóloga a MutS/genética , Polimorfismo de Nucleotídeo Único , Grupos Populacionais/genética , Alelos , Linhagem Celular , Mapeamento Cromossômico , Biologia Computacional/métodos , Frequência do Gene , Estudo de Associação Genômica Ampla , Genômica , Haplótipos , Humanos , Desequilíbrio de Ligação , Anotação de Sequência Molecular
5.
Biol Res ; 46(2): 161-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23959014

RESUMO

DNA repair is one of the central defense mechanisms against mutagenic exposures. Inherited SNPs of DNA repair genes may contribute to variations in DNA repair capacity and susceptibility to cancer. Due to the presence of these variants, inter-individual and ethnic differences in DNA repair capacity have been established in various populations. Saudi Arabia harbors enormous genetic and cultural diversity. In the present study we aimed to determine the genotype and allele frequencies of XRCC1 Arg399Gln (rs25487), XRCC3 Thr241Met (rs861539), XPD Lys751Gln (rs13181), and OGG1 Ser326Cys (rs1052133) gene polymorphisms in 386 healthy individuals residing in the central region of Saudi Arabia and compare them with HapMap and other populations. The genotype and allele frequencies of the four DNA repair gene loci in central Saudi population showed a distinctive pattern. Furthermore, comparison of polymorphisms in these genes with other populations also showed a unique pattern for the central Saudi population. To the best of our knowledge, this is the first report that deals with these DNA repair gene polymorphisms among the central Saudi population.


Assuntos
DNA Glicosilases/genética , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Polimorfismo de Nucleotídeo Único/genética , Proteína Grupo D do Xeroderma Pigmentoso/genética , Adulto , Idoso , Alelos , Distribuição de Qui-Quadrado , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Arábia Saudita , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
6.
Int J Mol Sci ; 14(2): 3921-45, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23434671

RESUMO

Although rice resistance plays an important role in controlling the brown planthopper (BPH), Nilaparvata lugens, not all varieties have the same level of protection against BPH infestation. Understanding the molecular interactions in rice defense response is an important tool to help to reveal unexplained processes that underlie rice resistance to BPH. A proteomics approach was used to explore how wild type IR64 and near-isogenic rice mutants with gain and loss of resistance to BPH respond during infestation. A total of 65 proteins were found markedly altered in wild type IR64 during BPH infestation. Fifty-two proteins associated with 11 functional categories were identified using mass spectrometry. Protein abundance was less altered at 2 and 14 days after infestation (DAI) (T1, T2, respectively), whereas higher protein levels were observed at 28 DAI (T3). This trend diminished at 34 DAI (T4). Comparative analysis of IR64 with mutants showed 22 proteins that may be potentially associated with rice resistance to the brown planthopper (BPH). Ten proteins were altered in susceptible mutant (D1131) whereas abundance of 12 proteins including S-like RNase, Glyoxalase I, EFTu1 and Salt stress root protein "RS1" was differentially changed in resistant mutant (D518). S-like RNase was found in greater quantities in D518 after BPH infestation but remained unchanged in IR64 and decreased in D1131. Taken together, this study shows a noticeable level of protein abundance in the resistant mutant D518 compared to the susceptible mutant D1131 that may be involved in rendering enhanced level of resistance against BPH.

7.
Mar Drugs ; 10(1): 84-105, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22363222

RESUMO

The effects of Tasco®, a product made from the brown seaweed (Ascophyllum nodosum) were tested for the ability to protect Caenorhabditis elegans against Pseudomonas aeruginosa infection. A water extract of Tasco® (TWE) reduced P. aeruginosa inflicted mortality in the nematode. The TWE, at a concentration of 300 µg/mL, offered the maximum protection and induced the expression of innate immune response genes viz.; zk6.7 (Lypases), lys-1 (Lysozyme), spp-1 (Saponin like protein), f28d1.3 (Thaumatin like protein), t20g5.7 (Matridin SK domain protein), abf-1 (Antibacterial protein) and f38a1.5 (Lectin family protein). Further, TWE treatment also affected a number of virulence components of the P. aeuroginosa and reduced its secreted virulence factors such as lipase, proteases and toxic metabolites; hydrogen cyanide and pyocyanin. Decreased virulence factors were associated with a significant reduction in expression of regulatory genes involved in quorum sensing, lasI, lasR, rhlI and rhlR. In conclusion, the TWE-treatment protected the C. elegans against P. aeruginosa infection by a combination of effects on the innate immunity of the worms and direct effects on the bacterial quorum sensing and virulence factors.


Assuntos
Ascophyllum/metabolismo , Caenorhabditis elegans/imunologia , Pseudomonas aeruginosa/patogenicidade , Animais , Biofilmes/efeitos dos fármacos , Caenorhabditis elegans/genética , Caenorhabditis elegans/microbiologia , Imunidade Inata/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/metabolismo , Percepção de Quorum/efeitos dos fármacos , Fatores de Virulência/metabolismo
8.
Mar Drugs ; 9(11): 2256-2282, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22163185

RESUMO

Tasco(®), a commercial product manufactured from the brown alga Ascophyllum nodosum, has been shown to impart thermal stress tolerance in animals. We investigated the physiological, biochemical and molecular bases of this induced thermal stress tolerance using the invertebrate animal model, Caenorhabiditis elegans. Tasco(®) water extract (TWE) at 300 µg/mL significantly enhanced thermal stress tolerance as well as extended the life span of C. elegans. The mean survival rate of the model animals under thermal stress (35 °C) treated with 300 µg/mL and 600 µg/mL TWE, respectively, was 68% and 71% higher than the control animals. However, the TWE treatments did not affect the nematode body length, fertility or the cellular localization of daf-16. On the contrary, TWE under thermal stress significantly increased the pharyngeal pumping rate in treated animals compared to the control. Treatment with TWE also showed differential protein expression profiles over control following 2D gel-electrophoresis analysis. Furthermore, TWE significantly altered the expression of at least 40 proteins under thermal stress; among these proteins 34 were up-regulated while six were down-regulated. Mass spectroscopy analysis of the proteins altered by TWE treatment revealed that these proteins were related to heat stress tolerance, energy metabolism and a muscle structure related protein. Among them heat shock proteins, superoxide dismutase, glutathione peroxidase, aldehyde dehydrogenase, saposin-like proteins 20, myosin regulatory light chain 1, cytochrome c oxidase RAS-like, GTP-binding protein RHO A, OS were significantly up-regulated, while eukaryotic translation initiation factor 5A-1 OS, 60S ribosomal protein L18 OS, peroxiredoxin protein 2 were down regulated by TWE treatment. These results were further validated by gene expression and reporter gene expression analyses. Overall results indicate that the water soluble components of Tasco(®) imparted thermal stress tolerance in the C. elegans by altering stress related biochemical pathways.


Assuntos
Ascophyllum/química , Regulação para Baixo , Transtornos de Estresse por Calor/prevenção & controle , Regulação para Cima , Animais , Caenorhabditis elegans , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Eletroforese em Gel Bidimensional , Perfilação da Expressão Gênica , Genes Reporter , Espectrometria de Massas , Faringe/metabolismo , Proteínas/genética , Solubilidade , Taxa de Sobrevida , Fatores de Tempo
9.
Int J Mol Sci ; 12(7): 4214-36, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21845074

RESUMO

Heat shock proteins are ubiquitous, induced under a number of environmental and metabolic stresses, with highly conserved DNA sequences among mammalian species. Camelus dromedaries (the Arabian camel) domesticated under semi-desert environments, is well adapted to tolerate and survive against severe drought and high temperatures for extended periods. This is the first report of molecular cloning and characterization of full length cDNA of encoding a putative stress-induced heat shock HSPA6 protein (also called HSP70B') from Arabian camel. A full-length cDNA (2417 bp) was obtained by rapid amplification of cDNA ends (RACE) and cloned in pET-b expression vector. The sequence analysis of HSPA6 gene showed 1932 bp-long open reading frame encoding 643 amino acids. The complete cDNA sequence of the Arabian camel HSPA6 gene was submitted to NCBI GeneBank (accession number HQ214118.1). The BLAST analysis indicated that C. dromedaries HSPA6 gene nucleotides shared high similarity (77-91%) with heat shock gene nucleotide of other mammals. The deduced 643 amino acid sequences (accession number ADO12067.1) showed that the predicted protein has an estimated molecular weight of 70.5 kDa with a predicted isoelectric point (pI) of 6.0. The comparative analyses of camel HSPA6 protein sequences with other mammalian heat shock proteins (HSPs) showed high identity (80-94%). Predicted camel HSPA6 protein structure using Protein 3D structural analysis high similarities with human and mouse HSPs. Taken together, this study indicates that the cDNA sequences of HSPA6 gene and its amino acid and protein structure from the Arabian camel are highly conserved and have similarities with other mammalian species.


Assuntos
Camelus/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/química , DNA Complementar/metabolismo , Proteínas de Choque Térmico HSP70/química , Proteínas de Choque Térmico HSP70/genética , Humanos , Masculino , Camundongos , Modelos Moleculares , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Filogenia , Estrutura Terciária de Proteína , RNA/química , RNA/metabolismo , Alinhamento de Sequência , Análise de Sequência de RNA , Homologia de Sequência de Aminoácidos
10.
J Med Biochem ; 38(1): 13-21, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30820179

RESUMO

BACKGROUND: Mutations in BRCA1 gene have been implicated in ovarian cancers, and BRCA testing may be conducted in high-risk women. This study was designed to determine the frequency of three single nucleotide polymorphisms (SNPs) variants in BRCA1 gene and BRCA1 expression in Saudi females with ovarian cancer. METHODS: Expression levels of mRNA of BRCA1 gene were studied in 10 ovarian cancer and 10 normal ovarian tissues, by quantitative real time polymerase chain reaction (qPCR). The study also included 28 females who had suffered from ovarian cancer and had been successfully operated upon and 90 healthy females with no history of cancer. Blood was drawn in EDTA tubes and used for extraction of DNA. The genotyping was carried out using Taqman® SNP Genotyping kit by RT-PCR. The variants investigated included c.871 T>C (rs799917), c.1040 G>A (rs4986852), c.181 T>G (rs28897672) in BRCA1 gene. RESULTS: The c.181 T>G (rs28897672) showed significantly different genotype and allele frequencies between the patients and the control subjects (p value = 0.002 and 0.02, respectively). The genotype TG was significantly protective (OR = 0.36, p value = 0.024). The mRNA expression of BRCA1 gene was found to be low in the ovarian cancer tissues. CONCLUSIONS: This study showed that c.181 T>G in BRCA1 genes is associated with the development of ovarian cancer in Saudis. More studies are needed to unveil other SNPs that may be associated with ovarian cancer and to understand the mechanism(s) involved in reducing the expression of BRCA1 gene in ovarian cancer tissues.

11.
Noncoding RNA Res ; 4(1): 1-14, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30891532

RESUMO

Internal ribosome entry site (IRES) sequences have become a valuable tool in the construction of gene transfer and therapeutic vectors for multi-cistronic gene expression from a single mRNA transcript. The optimal conditions for effective use of this sequence to construct a functional expression vector are not precisely defined but it is generally assumed that the internal ribosome entry site dependent expression of the second gene in such as cassette is less efficient than the cap-dependent expression of the first gene. Mainly tailoring inter-cistronic sequence significantly enhances IRES dependent second gene expression in bicistronic vector further in construction of optimised cassette for gene therapy of familial hypercholesterolemia. We tailored the size of the inter-cistronic spacer sequence at the 5' region of the internal ribosome entry site sequence using sequential deletions and demonstrated that the expression of the 3' gene can be significantly increased to similar levels as the cap-dependent expression of the 5' gene. Maximum expression efficiency of the downstream gene was obtained when the spacer is composed of 18-141 base pairs. In this case a single mRNA transcriptional unit containing both the first and the second Cistron was detected. Whilst constructs with spacer sequences of 216 bp or longer generate a single transcriptional unit containing only the first Cistron. This suggests that long spacers may affect transcription termination. When the spacer is 188 bp, both transcripts were produced simultaneously in most transfected cells, while a fraction of them expressed only the first but not the second gene. Expression analyses of vectors containing optimised cassettes clearly confirm that efficiency of gene transfer and biological activity of the expressed transgenic proteins in the transduced cells can be achieved. Furthermore, Computational analysis was carried out by molecular dynamics (MD) simulation to determine the most emerges as viable containing specific binding site and bridging of 5' and 3' ends involving direct RNA-RNA contacts and RNA-protein interactions. These results provide a mechanistic basis for translation stimulation and RNA resembling for the synergistic stimulation of cap-dependent translation.

12.
Pathol Oncol Res ; 23(3): 525-535, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27822728

RESUMO

The purpose of this study was to test the association between human 8-oxoguanine glycosylase 1 (hOGG1) gene polymorphisms and susceptibility to breast cancer in Saudi population. We have also aimed to screen the hOGG1 Ser326Cys polymorphism effect on structural and functional properties of the hOGG1 protein using in silico tools. We have analyzed four SNPs of hOGG1 gene among Saudi breast cancer patients along with healthy controls. Genotypes were screened using TaqMan SNP genotype analysis method. Experimental data was analyzed using Chi-square, t test and logistic regression analysis using SPSS software (v.16). In silco analysis was conducted using discovery studio and HOPE program. Genotypic analysis showed that hOGG1 rs1052133 (Ser326Cys) is significantly associated with breast cancer samples in Saudi population, however rs293795 (T >C), rs2072668 (C>G) and rs2075747 (G >A) did not show any association with breast cancer. The hOGG1 SNP rs1052133 (Ser326Cys) minor allele T showed a significant association with breast cancer samples (OR = 1.78, χ2 = 7.86, p = 0.02024). In silico structural analysis was carried out to compare the wild type (Ser326) and mutant (Cys326) protein structures. The structural prediction studies revealed that Ser326Cys variant may destabilize the protein structure and it may disturb the hOGG1 function. Taken together this is the first In silico study report to confirm Ser326Cys variant effect on structural and functional properties of hOGG1 gene and Ser326Cys role in breast cancer susceptibility in Saudi population.


Assuntos
Povo Asiático/genética , Neoplasias da Mama/genética , DNA Glicosilases/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Mama/patologia , Estudos de Casos e Controles , Feminino , Frequência do Gene/genética , Genótipo , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Arábia Saudita
13.
Biomed Pharmacother ; 88: 786-794, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28157655

RESUMO

Phytosterols are naturally occurring compounds in plants, structurally similar to cholesterol. The human diet is quite abundant in sitosterol and campesterol. Phytosterols are known to have various bioactive properties including reducing intestinal cholesterol absorption which alleviates blood LDL-cholesterol and cardiovascular problems. It is indicated that phytosterol rich diets may reduce cancer risk by 20%. Phytosterols may also affect host systems, enabling antitumor responses by improving immune response recognition of cancer, affecting the hormone dependent endocrine tumor growth, and by sterol biosynthesis modulation. Moreover, phytosterols have also exhibited properties that directly inhibit tumor growth, including reduced cell cycle progression, apoptosis induction, and tumor metastasis inhibition. The objective of this review is to summarize the current knowledge on occurrences, chemistry, pharmacokinetics and potential anticancer properties of phytosterols in vitro and in vivo. In conclusion, anticancer effects of phytosterols have strongly been suggested and support their dietary inclusion to prevent and treat cancers.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/prevenção & controle , Fitosteróis/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacocinética , Dieta , Humanos , Neoplasias/epidemiologia , Fitosteróis/química , Fitosteróis/farmacocinética
14.
Saudi J Biol Sci ; 23(3): 410-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27081368

RESUMO

The HSPA6, one of the members of large family of HSP70, is significantly up-regulated and has been targeted as a biomarker of cellular stress in several studies. Herein, conditions were optimized to increase the yield of recombinant camel HSPA6 protein in its native state, primarily focusing on the optimization of upstream processing parameters that lead to an increase in the specific as well as volumetric yield of the protein. The results showed that the production of cHSPA6 was increased proportionally with increased incubation temperature up to 37 °C. Induction with 10 µM IPTG was sufficient to induce the expression of cHSPA6 which was 100 times less than normally used IPTG concentration. Furthermore, the results indicate that induction during early to late exponential phase produced relatively high levels of cHSPA6 in soluble form. In addition, 5 h of post-induction incubation was found to be optimal to produce folded cHSPA6 with higher specific and volumetric yield. Subsequently, highly pure and homogenous cHSPA6 preparation was obtained using metal affinity and size exclusion chromatography. Taken together, the results showed successful production of electrophoretically pure recombinant HSPA6 protein from Camelus dromedarius in Escherichia coli in milligram quantities from shake flask liquid culture.

15.
Onco Targets Ther ; 9: 269-77, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26834486

RESUMO

The present study aimed at investigating the relationship between rs1801320 (G>C), rs1801321 (G>T), and rs2619681 (C>T) RAD51 gene polymorphisms and the risk of breast cancer development in Saudi females. The genotypes were analyzed using TaqMan genotyping assay and polymerase chain reaction-restriction fragment length polymorphism. The genotype and allele frequencies were computed using chi-square or Fisher's exact test (two-tailed) by SPSS 21 software. The results showed that rs1801321G>T GG genotype and G allele frequency were strongly (P<0.0001) related to an elevated risk of breast cancer, while the mutant T allele appeared to provide protection against breast cancer development as observed from the significantly lower (P<0.0001) frequencies of the TT and GT genotypes in cancer patients compared to the healthy controls. The variant rs1801320G>C showed no significant differences in the frequencies of the genotypes and alleles in the patients and the control groups. The CC genotype and C allele frequency of rs2619681 (C>T) variant were significantly (P=0.012) higher in cancer patients, whereas the T allele showed a protective effect against cancer development. The frequencies of the three single-nucleotide polymorphisms did not differ in cancer patients with different tumor grades and human epidermal growth factor receptor 2 status (+ or -). However, the genotype frequency of rs1801320 (135G>C) differed in the patients with estrogen receptor (ER)+ and ER-, where CC genotype showed a significantly higher prevalence in the females with ER- who were suffering from breast cancer. In addition, the frequency of C allele of rs2619681 (C>T) was also significantly higher in the breast cancer patients who were ER+ and progesterone receptor (PR)+ compared to those with ER- and PR-. In the Saudi females, rs1801320 did not show an association with risk of breast cancer. Taken together, the results suggest that RAD51 rs1801321 polymorphism may be involved in the etiology of breast cancer in the Saudi females; however, further studies are necessary to confirm this relation.

16.
Gene ; 591(1): 214-226, 2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27401137

RESUMO

Autosomal recessive polycystic kidney disease (ARPKD) a rare genetic disorder, described by formation of cysts in the kidney. A targeted customized sequencing of genes implicated in ARPKD phenotype was performed to identify candidate variants using the Ion torrent PGM next-generation sequencing. The results identified likely pathogenic disease causing variants during the validation process. Four potential pathogenic variants [c.4870C>T, p.(Arg1624Trp)], [c.5725C>T, p.(Arg1909Trp)], c.1736C>T, p.(Thr579Met)] and [(c.10628T>G), p.(Leu3543Trp)] were observed in PKHD1 gene among 12 out of 18 samples. The rest of the patient samples also showed few variants in ADPKD (Autosomal Dominant Polycystic Kidney Disease) disease causing genes PKD1 and PKD2 i.e. [c.12433G>A, p.(Val4145Ile)] and [c.1445T>G, p.(Phe482Cys)], respectively. All causative variants were validated by capillary sequencing, confirming the presence of a novel homozygous variants [c.10628T>G, p.(Leu3543Trp)] found in exon 61 of a male proband. All potentially deleterious variants identified in PKHD1, PKD1, and PKD2 gene, also exhibited pathologically or clinically significance based on the computational predictions involved in predicting the impact of non-synonymous SNPs (nsSNPs) on protein function such as Sorting Intolerant From Tolerant (SIFT) and Polymorphism Phenotyping (PolyPhen2). SIFT classified 50% of our nsSNPs as "deleterious", while PolyPhen2 identified 45% of our nsSNPs as "Probably damaged" and the results from both programs were largely complementary. Taken together, these results suggest that the NGS strategies provide a fast, accurate and cost-effective molecular diagnostic tool for identifying mutations in targeted genes sequence analysis.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Rim Policístico Autossômico Recessivo/genética , Sequência de Bases , Feminino , Ontologia Genética , Estudos de Associação Genética , Humanos , Masculino , Simulação de Dinâmica Molecular , Anotação de Sequência Molecular , Mutação/genética , Rim Policístico Autossômico Recessivo/diagnóstico , Polimorfismo de Nucleotídeo Único/genética , Reprodutibilidade dos Testes
17.
Genom Data ; 10: 127-134, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27843768

RESUMO

A targeted customized sequencing of genes implicated in autosomal recessive polycystic kidney disease (ARPKD) phenotype was performed to identify candidate variants using the Ion torrent PGM next-generation sequencing. The results identified four potential pathogenic variants in PKHD1 gene [c.4870C > T, p.(Arg1624Trp), c.5725C > T, p.(Arg1909Trp), c.1736C > T, p.(Thr579Met) and c.10628T > G, p.(Leu3543Trp)] among 12 out of 18 samples. However, one variant c.4870C > T, p.(Arg1624Trp) was common among eight patients. Some patient samples also showed few variants in autosomal dominant polycystic kidney disease (ADPKD) disease causing genes PKD1 and PKD2 such as c.12433G > A, p.(Val4145Ile) and c.1445T > G, p.(Phe482Cys), respectively. All causative variants were validated by capillary sequencing and confirmed the presence of a novel homozygous variant c.10628T > G, p.(Leu3543Trp) in a male proband. We have recently published the results of these studies (Edrees et al., 2016). Here we report for the first time the effect of the common mutation p.(Arg1624Trp) found in eight samples on the protein structure and function due to the specific amino acid changes of PKHD1 protein using molecular dynamics simulations. The computational approaches provide tool predict the phenotypic effect of variant on the structure and function of the altered protein. The structural analysis with the common mutation p.(Arg1624Trp) in the native and mutant modeled protein were also studied for solvent accessibility, secondary structure and stabilizing residues to find out the stability of the protein between wild type and mutant forms. Furthermore, comparative genomics and evolutionary analyses of variants observed in PKHD1, PKD1, and PKD2 genes were also performed in some mammalian species including human to understand the complexity of genomes among closely related mammalian species. Taken together, the results revealed that the evolutionary comparative analyses and characterization of PKHD1, PKD1, and PKD2 genes among various related and unrelated mammalian species will provide important insights into their evolutionary process and understanding for further disease characterization and management.

18.
Gene ; 565(1): 76-84, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25839937

RESUMO

Familial hypercholesterolemia (FH) is an autosomal dominant inherited disease characterized by elevated plasma low-density lipoprotein cholesterol (LDL-C). It is an autosomal dominant disease, caused by variants in Ldlr, ApoB or Pcsk9, which results in high levels of LDL-cholesterol (LDL-C) leading to early coronary heart disease. Sequencing whole genome for screening variants for FH are not suitable due to high cost. Hence, in this study we performed targeted customized sequencing of FH 12 genes (Ldlr, ApoB, Pcsk9, Abca1, Apoa2, Apoc3, Apon2, Arh, Ldlrap1, Apoc2, ApoE, and Lpl) that have been implicated in the homozygous phenotype of a proband pedigree to identify candidate variants by NGS Ion torrent PGM. Only three genes (Ldlr, ApoB, and Pcsk9) were found to be highly associated with FH based on the variant rate. The results showed that seven deleterious variants in Ldlr, ApoB, and Pcsk9 genes were pathological and were clinically significant based on predictions identified by SIFT and PolyPhen. Targeted customized sequencing is an efficient technique for screening variants among targeted FH genes. Final validation of seven deleterious variants conducted by capillary resulted to only one novel variant in Ldlr gene that was found in exon 14 (c.2026delG, p. Gly676fs). The variant found in Ldlr gene was a novel heterozygous variant derived from a male in the proband.


Assuntos
Apolipoproteína B-100/genética , Doença das Coronárias/genética , Hiperlipoproteinemia Tipo II/genética , Pró-Proteína Convertases/genética , Receptores de LDL/genética , Serina Endopeptidases/genética , Doença das Coronárias/etiologia , Feminino , Variação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Hiperlipoproteinemia Tipo II/complicações , Masculino , Linhagem , Pró-Proteína Convertase 9 , Análise de Sequência de DNA
19.
Dis Markers ; 2015: 869512, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26257461

RESUMO

OBJECTIVE: The aim of this study was to investigate the role of APE1 Asp148Glu polymorphism in breast cancer progression in Saudi population. METHODS: We examined the genetic variations (rs1130409) in the DNA base excision repair gene APE1 at codon 148 (Asp148Glu) and its association with breast cancer risk using genotypic assays and in silico structural as well as functional predictions. In silico structural analysis was performed with Asp148Glu allele and compared with the predicted native protein structure. The wild and mutant 3D structures of APE1 were compared and analyzed using solvent accessibility models for protein stability confirmation. RESULTS: Genotypic analysis of APE1 (rs1130409) showed statistically significant association of Asp148Glu with elevated susceptibility to breast cancer. The in silico analysis results indicated that the nsSNP Asp148Glu may cause changes in the protein structure and is associated with breast cancer risk. CONCLUSION: Taken together, this is the first report that established that Asp148Glu variant has structural and functional effect on the APE1 and may play an important role in breast cancer progression in Saudi population.


Assuntos
Neoplasias da Mama/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Polimorfismo de Nucleotídeo Único , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Arábia Saudita
20.
J Plant Physiol ; 160(8): 859-63, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12964861

RESUMO

Phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) and tyrosine ammonia-lyase (TAL, 4.3.1.), the key enzymes of the phenylpropanoid pathway, are inducible in response to biotic (such as chitin from fungal cell walls) and abiotic cues. Application of chitin and chitosan to soybean leaf tissues caused increased activity of PAL and TAL enzymes. The elevation of enzyme activity was dependent on the chain length of the oligomers and time after treatment. The hexamer of chitin and pentamer of chitosan produced the maximum activities at 36 h after treatment as compared to controls. Total phenolic content of soybean leaves increased following chitosan and chitin oligomer treatments, showing a positive correlation between enzyme activity and total phenolic content.


Assuntos
Amônia-Liases/metabolismo , Quitina/análogos & derivados , Quitina/metabolismo , Glycine max/metabolismo , Oligossacarídeos/metabolismo , Fenilalanina Amônia-Liase/metabolismo , Amônia-Liases/isolamento & purificação , Sequência de Carboidratos , Quitosana , Cinética , Dados de Sequência Molecular , Oligossacarídeos/química , Oligossacarídeos/farmacologia , Fenilalanina Amônia-Liase/isolamento & purificação , Folhas de Planta/enzimologia , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Glycine max/enzimologia
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