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1.
J Cell Biochem ; 125(4): e30534, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38358025

RESUMO

Missense mutations in the DNA binding domain of p53 are observed frequently in esophageal squamous cell carcinoma (ESCC). Recent studies have revealed the potentially oncogenic transcriptional networks regulated by mutant p53 proteins. However, majority of these studies have focused on common "hotspot" p53 mutations while rarer mutations are poorly characterized. In this study, we report the characterization of rare, "non-hotspot" p53 mutations from ESCC. In vitro tumorigenic assays performed following ectopic-expression of certain "non-hotspot" mutant p53 proteins caused enhancement of oncogenic properties in squamous carcinoma cell lines. Genome-wide transcript profiling of ESCC tumor samples stratified for p53 status, revealed several genes exhibiting elevated transcript levels in tumors harboring mutant p53. Of these, ARF6, C1QBP, and TRIM23 were studied further. Reverse transcription-quantitative PCR (RT-qPCR) performed on RNA isolated from ESCC tumors revealed significant correlation of TP53 transcript levels with those of the three target genes. Ectopic expression of wild-type and several mutant p53 forms followed by RT-qPCR, chromatin affinity-purification (ChAP), and promoter-luciferase assays indicated the exclusive recruitment of p53 mutants-P190T and P278L, to the target genes leading to the activation of expression. Several functional assays following knockdown of the target genes revealed a significant suppression of tumorigenicity in squamous carcinoma cell lines. Rescue experiments confirmed the specificity of the knockdown. The tumorigenic effects of the genes were confirmed in nude mice xenograft assays. This study has therefore identified novel oncogenic targets of "non-hotspot" mutant p53 proteins relevant for ESCC besides validating the functional heterogeneity of the spectrum of tumor-specific p53 mutations.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Animais , Camundongos , Humanos , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Neoplasias Esofágicas/patologia , Camundongos Nus , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proliferação de Células , Proteínas de Ligação ao GTP/genética , Proteínas de Transporte/genética , Proteínas Mitocondriais/genética
2.
Dalton Trans ; 52(16): 5297-5311, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-36988241

RESUMO

Hydrogen fuel plays a ubiquitous role in empowering the sustainable green energy economy. As an eco-friendly production method for hydrogen, photo-assisted water splitting is accepted to be the most reliable. However, the fabrication of stable and efficient photocatalysts is challenging. To overcome this difficulty, here we present a novel and inexpensive oxidant-promoted ultrasonic-assisted liquid phase layer exfoliation technique to fabricate a CdS/H-MoS2 nano hybrid. The newly fabricated CdS/H-MoS2 shows a hydrogen evolution rate of 162.4 mmol g-1h-1, which is 16 times higher compared to that of CdS/Pt and 67 times higher compared to that of bare CdS. Theoretical results clearly demonstrate a built-in electrostatic potential in the heterostructure junction, and that a shift in water reduction potential plays a key role in the enhancement of hydrogen production rate. We believe that the proposed experimental strategies and theoretical studies will open up a new avenue to develop new photocatalysts with high hydrogen evolution efficiency.

3.
Dalton Trans ; 51(48): 18693-18707, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36448739

RESUMO

Solar-driven hydrogen generation using single-semiconductor photocatalysts for hydrogen evolution seems to be challenging due to their poor solar to fuel conversion efficiency because of their fast charge carrier recombination. The ternary heterostructure was prepared by an advanced approach to suppress the recombination of photogenerated charge carriers and has contributed a new platform for designing highly efficient photocatalytic systems. Herein, we fabricated a ternary heterojunction with ultrathin WS2-SnS2 nanosheets and CdS nanorods, and the photocatalytic activity was studied. The optimized CdS/SnS2-WS2 (6 wt%) nanostructures were found to be highly stable and exhibited the highest hydrogen evolution rate of 232.45 mmol g-1 h-1, which was almost 93-fold higher than that of the pristine CdS nanorods. Also, Density Functional Theory (DFT) calculations confirmed that the favorable band alignment for charge transport and superior catalytic activity of the newly fabricated ternary nanostructures make them a potential candidate for solar-driven hydrogen production.

4.
Mater Today Proc ; 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33520674

RESUMO

The epic Covid sickness 2019 (COVID-19) has turned into the significant danger to humankind in year 2020. The pandemic COVID-19 flare-up has influenced more than 2.7 million individuals and caused around 187 thousand fatalities worldwide [1] inside scarcely any months of its first appearance in Wuhan city of China and the number is developing quickly in various pieces of world. As researcher everywhere on the world are battling to discover the fix and treatment for COVID-19, the urgent advance fighting against COVID-19 is the screening of immense number of associated cases for disconnection and isolate with the patients. One of the key methodologies in screening of COVID-19 can be chest radiological imaging. The early investigations on the patients influenced by COVID-19 shows the attributes variations from the norm in chest radiography pictures. This introduced a chance to utilize distinctive counterfeit clever (AI) frameworks dependent on profound picking up utilizing chest radiology pictures for the recognition of COVID-19 and numerous such framework were proposed indicating promising outcomes. In this paper, we proposed a profound learning based convolution neural organization to characterize COVID-19, Pneumonia and Normal cases from chest radiology pictures. The proposed convolution neural organization (CNN) grouping model had the option to accomplish exactness of 94.85% on test dataset. The trial was completed utilizing the subset of information accessible in GitHub and Kaggle.

5.
J Cell Physiol ; 235(5): 4559-4570, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31637714

RESUMO

Though primarily a tumor suppressor, TP53 harboring specific missense mutations located in the region encoding the DNA binding domain exhibits a gain of function by transcriptional activation of oncogenes. We performed microarray-based messenger RNA profiling of squamous cell carcinoma of the oral tongue (SCCOT) and identified significant elevation of SMARCD1 in samples exhibiting p53 nuclear stabilization. Activation of SMARCD1 by mutant p53 was confirmed by evaluation of additional tongue cancer samples as well as The Cancer Genome Atlas expression datasets. SMARCD1 knockdown in HNSCC cells resulted in a significant reduction in several tumorigenic characteristics including cell viability, ability to form colonies in liquid and solid media and cell migration. We identified significantly increased SMARCD1 transcript levels in tumor versus matched normal samples in SCCOT as well as in other cancer types. Increased SMARCD1 expression predicted poor survival in HNSCC tumors harboring missense p53 mutations. Our results suggest SMARCD1 to be a novel transcriptional target of mutant p53.


Assuntos
Proteínas Cromossômicas não Histona/genética , Mutação , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Transcrição Gênica , Proteína Supressora de Tumor p53/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Proteínas Cromossômicas não Histona/metabolismo , Bases de Dados Genéticas , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Bucais/genética , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Proteína Supressora de Tumor p53/metabolismo
6.
RSC Adv ; 9(59): 34158-34165, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-35530013

RESUMO

The temperature dependence of the stability of bulk BaZrO3 (BZO) and of the vacancies in this material are investigated by considering phonon contributions to the free energy. The stability diagram of BZO is determined for different chemical environments. With increasing temperature the stability region becomes smaller which is particularly caused by the strong temperature dependence of the chemical potential of gaseous oxygen. The free formation energy of Ba, Zr, and O vacancies in BZO is calculated for all possible charge states and for different atomic reservoirs. While the free formation energy of Zr vacancies is strongly influenced by temperature a weaker dependence is found for Ba and O vacancies. This also has an effect on the charge transition levels at different temperatures. The present results demonstrate that O poor reservoir conditions and a Fermi level close to the valence band maximum favour a high concentration of doubly positively charged O vacancies which is a prerequisite to get a large number of protonic defects and good proton conductivity. In such a chemical environment the number of Ba and Zr vacancies is low so that Ba and Zr deficiencies are not an important issue and BZO remains sufficiently stable.

7.
Sci Rep ; 8(1): 8005, 2018 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-29789634

RESUMO

Recently the solar energy, an inevitable part of green energy source, has become a mandatory topics in frontier research areas. In this respect, non-centrosymmetric ferroelectric perovskites with open circuit voltage (VOC) higher than the bandgap, gain tremendous importance as next generation photovoltaic materials. Here a non-toxic co-doped Ba1-x(Bi0.5Li0.5) x TiO3 ferroelectric system is designed where the dopants influence the band topology in order to enhance the photovoltaic effect. In particular, at the optimal doping concentration (x opt ~ 0.125) the sample reveals a remarkably high photogenerated field EOC = 320 V/cm (VOC = 16 V), highest ever reported in any bulk polycrystalline non-centrosymmetric systems. The band structure, examined through DFT calculations, suggests that the shift current mechanism is key to explain the large enhancement in photovoltaic effect in this family.

8.
J Mol Med (Berl) ; 96(2): 135-146, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29124284

RESUMO

Our previous extensive analysis revealed a significant proportion of early-onset colorectal tumors from India to be localized to the rectum in younger individuals and devoid of deregulated Wnt/ß-catenin signaling. In the current study, we performed a comprehensive genome-wide analysis of clinically well-annotated microsatellite stable early-onset sporadic rectal cancer (EOSRC) samples. Results revealed extensive DNA copy number alterations in rectal tumors in the absence of deregulated Wnt/ß-catenin signaling. More importantly, transcriptome profiling revealed a (non-Wnt/ß-catenin, non-MSI) genetic signature that could efficiently and specifically identify Wnt- rectal cancer. The genetic signature included a significant representation of genes belonging to Ca2+/NFAT signaling pathways that were validated in additional samples. The validated NFAT target genes exhibited significantly higher expression levels than canonical Wnt/ß-catenin targets in Wnt- samples, an observation confirmed in other CRC expression data sets as well. We confirmed the validated genes to be transcriptionally regulated by NFATc1 by (a) evaluating their respective transcript levels and (b) performing promoter-luciferase and chromatin immunoprecipitation assays following ectopic expression as well as knockdown of NFATc1 in CRC cells. NFATc1 and its targets RUNX2 and GSN could drive increased migration in CRC cells. Finally, the validated genes were associated with poor survival in the cancer genome atlas CRC expression data set. This study is the first comprehensive molecular characterization of EOSRC that appears to be driven by noncanonical tumorigenesis pathways. KEY MESSAGES: Early-onset sporadic rectal cancer exhibits DNA gain and loss without Wnt activation. Ca2+/NFAT signaling appears to be activated in the absence of Wnt activation. An eight-gene genetic signature distinguishes Wnt+ and Wnt- rectal tumors. NFAT and its target genes regulate tumorigenic properties in CRC cells.


Assuntos
Cálcio/metabolismo , Fatores de Transcrição NFATC/metabolismo , Neoplasias Retais/metabolismo , Proteínas Wnt/metabolismo , Adulto , Idade de Início , Células HCT116 , Humanos , Índia , Pessoa de Meia-Idade , Neoplasias Retais/genética , Transdução de Sinais , Adulto Jovem
9.
J Biosci ; 42(4): 695-707, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29229887

RESUMO

ß-Catenin is essential for embryonic development and required for cell renewal/regeneration in adult life. Cellular ß-catenin exists in three different pools: membranous, cytoplasmic and nuclear. In this review, we focus on functions of the nuclear pool in relation to tumorigenesis. In the nucleus, beta-catenin functions as both activator and repressor of transcription in a context-dependent manner. It promotes cell proliferation and supports tumour growth by enhancing angiogenesis. ß-Catenin-mediated signalling regulates cancer cell metabolism and is associated with tumour-initiating cells in multiple malignancies. In addition, it functions as both pro- and anti-apoptotic factor besides acting to inhibit recruitment of inflammatory anti-tumour T-cells. Thus, ß-catenin appears to possess a multifaceted nuclear function that may significantly impact tumour initiation and progression.


Assuntos
Núcleo Celular/metabolismo , Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , Neovascularização Patológica/genética , beta Catenina/genética , Núcleo Celular/imunologia , Proliferação de Células , Transformação Celular Neoplásica/imunologia , Transformação Celular Neoplásica/patologia , Transição Epitelial-Mesenquimal/genética , Transição Epitelial-Mesenquimal/imunologia , Humanos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/imunologia , Neoplasias/imunologia , Neoplasias/patologia , Células-Tronco Neoplásicas/imunologia , Células-Tronco Neoplásicas/patologia , Neovascularização Patológica/imunologia , Neovascularização Patológica/patologia , Transdução de Sinais , Linfócitos T/imunologia , Linfócitos T/patologia , beta Catenina/imunologia
12.
Mol Carcinog ; 54(12): 1807-14, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25420488

RESUMO

Lynch syndrome (LS), the most common form of familial CRC predisposition that causes tumor onset at a young age, is characterized by the presence of microsatellite instability (MSI) in tumors due to germline inactivation of mismatch repair (MMR) system. Two MMR genes namely MLH1 and MSH2 account for majority of LS cases while MSH6 and PMS2 may account for a minor proportion. In order to identify MMR genes causing LS in India, we analyzed MSI and determined expression status of the four MMR genes in forty eight suspected LS patient colorectal tumor samples. Though a majority exhibited MSI, only 58% exhibited loss of MMR expression, a significantly low proportion compared to reports from other populations. PCR-DNA sequencing and MLPA-based mutation and exonic deletion/duplication screening respectively, revealed genetic lesions in samples with and without MMR gene expression. Interestingly, tumor samples with and without MMR expression exhibited significant differences with respect to histological (mucin content) and molecular (instability exhibited by mononucleotide microsatellites) features. The study has revealed for the first time a significant proportion of LS tumors not exhibiting loss of MMR expression.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo de Erro de Pareamento de DNA/genética , Expressão Gênica/genética , Adulto , Idoso , Neoplasias Colorretais/genética , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Mutação/genética
13.
Int J Biol Macromol ; 74: 447-57, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25541359

RESUMO

The presence of occult metastases at the time of diagnosis together with the lack of effective chemotherapies pose a dire need for designing new and targeted therapeutics for pancreatic cancer. Fucoidans from brown algae can be regarded as potential candidates in view of their antioxidant, anti-cancer and anti-angiogenic potential. Herein, we investigated the antioxidant and anti-cancer effects of fucoidans, sulfated polysaccharides from Turbinaria conoides (TCFE) in pancreatic cancer cell lines. TCFE exerted significant antioxidant activities against various free radicals. Significant inhibition of cell proliferation and, induction of apoptotic cell death were observed in pancreatic cancer cells in response to TCFE. Also, TCFE exhibited significant anti-angiogenic potential. Evidently, gelatin zymography revealed that TCFE inhibited matrix metalloproteases -2 and -9 activities in pancreatic cancer cells. These results clearly indicate that TCFE could serve as a potential 'deliverable' to alleviate pancreatic cancer progression by inhibiting tumor cell proliferation and angiogenesis.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Phaeophyceae/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Humanos , Neoplasias Pancreáticas , Polissacarídeos/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier
14.
J Cell Biochem ; 115(3): 566-74, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24130151

RESUMO

Phenylketonuria (PKU) is an autosomal recessive metabolic disorder caused by mutational inactivation of the phenylalanine hydroxylase (PAH) gene. Missense mutations are the most common PAH mutation type detected in PKU patients worldwide. We performed PAH mutation analysis in 27 suspected Indian PKU families (including 7 from our previous study) followed by structure and function analysis of specific missense and splice/insertion-deletion/nonsense mutations, respectively. Of the 27 families, disease-causing mutations were detected in 25. A total of 20 different mutations were identified of which 7 "unique" mutations accounted for 13 of 25 mutation positive families. The unique mutations detected exclusively in Indian PKU patients included three recurrent mutations detected in three families each. The 20 mutations included only 5 missense mutations in addition to 5 splice, 4 each nonsense and insertion-deletion mutations, a silent variant in coding region and a 3'UTR mutation. One deletion and two nonsense mutations were characterized to confirm significant reduction in mutant transcript levels possibly through activation of nonsense mediated decay. All missense mutations affected conserved amino acid residues and sequence and structure analysis suggested significant perturbations in the enzyme activity of respective mutant proteins. This is probably the first report of identification of a significantly low proportion of missense PAH mutations from PKU families and together with the presence of a high proportion of splice, insertion-deletion, and nonsense mutations, points to a unique PAH mutation profile in Indian PKU patients.


Assuntos
Códon sem Sentido/genética , Mutação INDEL/genética , Fenilalanina Hidroxilase/genética , Fenilcetonúrias/genética , Alelos , Povo Asiático/genética , Análise Mutacional de DNA , Feminino , Humanos , Índia , Masculino , Linhagem , Fenilalanina Hidroxilase/metabolismo , Fenilcetonúrias/etiologia , Fenilcetonúrias/patologia , Sítios de Splice de RNA/genética
15.
Cancer Res ; 73(1): 205-14, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23117887

RESUMO

PTEN is a well-defined tumor suppressor gene that antagonizes the PI3K/Akt pathway to regulate a multitude of cellular processes, such as survival, growth, motility, invasiveness, and angiogenesis. While the functions of PTEN have been studied extensively, the regulation of its activity during normal and disease conditions still remains incompletely understood. In this study, we identified the protein phosphatase-1 nuclear targeting subunit PNUTS (PPP1R10) as a PTEN-associated protein. PNUTS directly interacted with the lipid-binding domain (C2 domain) of PTEN and sequestered it in the nucleus. Depletion of PNUTS leads to increased apoptosis and reduced cellular proliferation in a PTEN-dependent manner. PNUTS expression was elevated in certain cancers compared with matched normal tissues. Collectively, our studies reveal PNUTS as a novel PTEN regulator and a likely oncogene.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Proto-Oncogenes/fisiologia , Proteínas de Ligação a RNA/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/genética , Imunofluorescência , Humanos , Immunoblotting , Imuno-Histoquímica , Imunoprecipitação , Neoplasias/genética , Proteínas Nucleares/genética , Transporte Proteico/fisiologia , Proto-Oncogene Mas , Interferência de RNA , RNA Interferente Pequeno , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
16.
Appl Radiat Isot ; 72: 128-32, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23208243

RESUMO

A simple synthesis of the dopamine transporter ligand [(18)F]FECNT with high radiochemical yield and short synthesis time, suitable for routine production is reported. Reaction of 2ß-carbomethoxy-3ß-(4-chlorophenyl)nortropane with [(18)F]2-fluoroethyl triflate ([(18)F]FEtOTf) at room temperature for 4 min provided [(18)F]FECNT in 84% decay corrected radiochemical yield. Since [(18)F]FEtOTf was prepared from [(18)F]2-fluoroethyl bromide that was isolated from its starting material, formation of unwanted side products and the amount of expensive precursor used could be greatly reduced. The overall radiochemical yields of [(18)F]FECNT were 40% (n=29) and the total synthesis time was ca. 100 min. The average specific activity of [(18)F]FECNT was 377.4 GBq/µmol (10.2 Ci/µmol).


Assuntos
Proteínas da Membrana Plasmática de Transporte de Dopamina/análise , Radioisótopos de Flúor/química , Nortropanos/síntese química , Cromatografia Líquida de Alta Pressão
17.
Hemoglobin ; 36(5): 497-503, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22734501

RESUMO

ß-Thalassemia (ß-thal) is a common single gene autosomal recessive disorder resulting in severe anemia due to reduced or absent ß-globin polypeptide synthesis. The disease is caused by mutations in the ß-globin gene; eight common mutations are proposed to cause the majority of ß-thal in India. However, the occurrence of a region-specific mutation spectrum in India has also been suggested. We had earlier carried out analyses of the ß-globin gene mutation spectrum from southern Indian states of Andhra Pradesh and Karnataka. In the current study, we have analyzed three of 73 transfusion-dependent patients visiting a referral hospital in Karnataka State, South India, who did not carry any of the 22 common ß-globin gene mutations as determined by reverse dot-blot analysis. The IVS-II-837 (T>G) (ß(+)) (HBB:c.316-14TG) mutation was detected in two of the three patients analyzed suggesting a higher occurrence of the mutation in ß-thal patients in Karnataka when compared to other regions of India. The rare polyadenylation (poly A) site (T>C) (AATAAA>AACAAA; ß(+)) mutation was detected in the third patient. The IVS-II-837 mutation was also identified in asymptomatic carrier parents during routine high performance liquid chromatography (HPLC)-based Hb A(1c) screening in suspected diabetes patients. This is the first report of the identification of ß-thal trait through HPLC-based diabetes screening in India, revealing the importance of linking diabetes screening with screening for thalassemia.


Assuntos
Mutação , Globinas beta/genética , Talassemia beta/genética , Adolescente , Adulto , Criança , Feminino , Genótipo , Geografia , Humanos , Índia/epidemiologia , Masculino , Adulto Jovem , Talassemia beta/epidemiologia
18.
J Cell Biochem ; 113(10): 3122-32, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22593002

RESUMO

Maple Syrup Urine Disease is a rare metabolic disorder caused by reduced/absent activity of the branched chain α-Ketoacid dehydrogenase enzyme complex. Mutations in BCKDHA, BCKDHB, and DBT, that encode important subunits of the enzyme complex namely E1α, E1ß, and E2, are the primary cause for the disease. We have performed the first molecular genetic analysis of MSUD from India on nine patients exhibiting classical MSUD symptoms. BCKDHA and BCKDHB mutations were identified in four and five patients, respectively including seven novel mutations namely the BCKDHA c.1249delC, c.1312T>C, and c.1561T>A and the BCKDHB c.401T>A, c.548G>A, c.964A>G, and c.1065delT. The BCKDHB c.970C>T (p.R324X) mutation was shown to trigger nonsense mediated decay-based degradation of the transcript. Seven of the total 11 mutations resulted in perturbations in the E1α or E1ß C-termini either through altered termination or through an amino acid change; these are expected to result in disruption of E1 enzyme complex assembly. Our study has therefore revealed that BCKDHA and BCKDHB mutations might be primarily responsible for MSUD in the Indian population.


Assuntos
3-Metil-2-Oxobutanoato Desidrogenase (Lipoamida)/química , Doença da Urina de Xarope de Bordo/genética , Complexos Multienzimáticos/química , Mutação de Sentido Incorreto , Regiões 3' não Traduzidas , 3-Metil-2-Oxobutanoato Desidrogenase (Lipoamida)/genética , Sequência de Aminoácidos , Aminoácidos/química , Sequência de Bases , Códon sem Sentido/química , Códon sem Sentido/genética , Análise Mutacional de DNA , Feminino , Testes Genéticos , Genoma Humano , Genótipo , Humanos , Índia , Lactente , Recém-Nascido , Masculino , Doença da Urina de Xarope de Bordo/diagnóstico , Dados de Sequência Molecular , Complexos Multienzimáticos/genética , Estabilidade de RNA , Alinhamento de Sequência , Análise de Sequência de Proteína , Deleção de Sequência
19.
Proc Natl Acad Sci U S A ; 109(5): E252-9, 2012 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-22233809

RESUMO

Defining the molecular genetic alterations underlying pancreatic cancer may provide unique therapeutic insight for this deadly disease. Toward this goal, we report here an integrative DNA microarray and sequencing-based analysis of pancreatic cancer genomes. Notable among the alterations newly identified, genomic deletions, mutations, and rearrangements recurrently targeted genes encoding components of the SWItch/Sucrose NonFermentable (SWI/SNF) chromatin remodeling complex, including all three putative DNA binding subunits (ARID1A, ARID1B, and PBRM1) and both enzymatic subunits (SMARCA2 and SMARCA4). Whereas alterations of each individual SWI/SNF subunit occurred at modest-frequency, as mutational "hills" in the genomic landscape, together they affected at least one-third of all pancreatic cancers, defining SWI/SNF as a major mutational "mountain." Consistent with a tumor-suppressive role, re-expression of SMARCA4 in SMARCA4-deficient pancreatic cancer cell lines reduced cell growth and promoted senescence, whereas its overexpression in a SWI/SNF-intact line had no such effect. In addition, expression profiling analyses revealed that SWI/SNF likely antagonizes Polycomb repressive complex 2, implicating this as one possible mechanism of tumor suppression. Our findings reveal SWI/SNF to be a central tumor suppressive complex in pancreatic cancer.


Assuntos
Montagem e Desmontagem da Cromatina , Proteínas Cromossômicas não Histona/fisiologia , Genes Supressores de Tumor , Neoplasias Pancreáticas/metabolismo , Fatores de Transcrição/fisiologia , Proteínas Cromossômicas não Histona/genética , Perfilação da Expressão Gênica , Humanos , Mutação , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Fatores de Transcrição/genética , Transcriptoma
20.
Mol Cell Biochem ; 360(1-2): 373-82, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21959974

RESUMO

Familial Hypertrophic Cardiomyopathy (FHC) is an autosomal dominant disorder affecting the cardiac muscle and exhibits varied clinical symptoms because of genetic heterogeneity. Several disease causing genes have been identified and most code for sarcomere proteins. In the current study, we have carried out clinical and molecular analysis of FHC patients from India. FHC was detected using echocardiography and by analysis of clinical symptoms and family history. Disease causing mutations in the ß-cardiac myosin heavy chain (MYH7) and Myosin binding protein C3 (MYBPC3) genes were identified using Polymerase Chain Reaction-Deoxyribose Nucleic Acid (PCR-DNA) sequencing. Of the 55 patient samples screened, mutations were detected in only nineteen in the two genes; MYBPC3 mutations were identified in 12 patients while MYH7 mutations were identified in five, two patients exhibited double heterozygosity. All four MYH7 mutations were missense mutations, whereas only 3/9 MYPBC3 mutations were missense mutations. Four novel mutations in MYBPC3 viz. c.456delC, c.2128G>A (p.E710K), c.3641G>A (p.W1214X), and c.3656T>C (p.L1219P) and one in MYH7 viz. c.965C>T (p.S322F) were identified. A majority of missense mutations affected conserved amino acid residues and were predicted to alter the structure of the corresponding mutant proteins. The study has revealed a greater frequency of occurrence of MYBPC3 mutations when compared to MYH7 mutations.


Assuntos
Miosinas Cardíacas/genética , Cardiomiopatia Hipertrófica Familiar/genética , Proteínas de Transporte/genética , Mutação de Sentido Incorreto , Cadeias Pesadas de Miosina/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , Miosinas Cardíacas/química , Pré-Escolar , Sequência Conservada , Feminino , Estudos de Associação Genética , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Cadeias Pesadas de Miosina/química , Peptidil Dipeptidase A/genética , Estrutura Terciária de Proteína , Análise de Sequência de DNA , Adulto Jovem
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