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1.
Genes (Basel) ; 14(1)2023 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-36672963

RESUMO

The SOX transcription factor family is pivotal in controlling aspects of development. To identify genotype-phenotype relationships of SOX proteins, we performed a non-biased study of SOX using 1890 open-reading frame and 6667 amino acid sequences in combination with structural dynamics to interpret 3999 gnomAD, 485 ClinVar, 1174 Geno2MP, and 4313 COSMIC human variants. We identified, within the HMG (High Mobility Group)- box, twenty-seven amino acids with changes in multiple SOX proteins annotated to clinical pathologies. These sites were screened through Geno2MP medical phenotypes, revealing novel SOX15 R104G associated with musculature abnormality and SOX8 R159G with intellectual disability. Within gnomAD, SOX18 E137K (rs201931544), found within the HMG box of ~0.8% of Latinx individuals, is associated with seizures and neurological complications, potentially through blood-brain barrier alterations. A total of 56 highly conserved variants were found at sites outside the HMG-box, including several within the SOX2 HMG-box-flanking region with neurological associations, several in the SOX9 dimerization region associated with Campomelic Dysplasia, SOX14 K88R (rs199932938) flanking the HMG box associated with cardiovascular complications within European populations, and SOX7 A379V (rs143587868) within an SOXF conserved far C-terminal domain heterozygous in 0.716% of African individuals with associated eye phenotypes. This SOX data compilation builds a robust genotype-to-phenotype association for a gene family through more robust ortholog data integration.


Assuntos
Proteínas de Grupo de Alta Mobilidade , Fatores de Transcrição SOX , Humanos , Proteínas de Grupo de Alta Mobilidade/química , Proteínas de Grupo de Alta Mobilidade/genética , Proteínas de Grupo de Alta Mobilidade/metabolismo , Fatores de Transcrição SOX/genética , Sequência de Aminoácidos , Dimerização , Genótipo , Fatores de Transcrição SOXF/genética , Fatores de Transcrição SOXF/metabolismo , Fatores de Transcrição SOXB2/genética , Fatores de Transcrição SOXB2/metabolismo , Fatores de Transcrição SOXE/genética
2.
Intractable Rare Dis Res ; 10(3): 179-189, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34466340

RESUMO

Fibrodysplasia Ossificans Progressiva (FOP) is a rare congenital intractable disease associated with a mutation in ACVR1 gene, characterized by skeleton malformations. Ascorbic acid (AA) and propranolol (PP) in combination is reported to minimize flare-ups in patients. FOP leukocyte phenotype may possibly be modulated by AA and PP treatment. In this study, expression of 22 potential target genes was analyzed by RT-PCR in peripheral blood mononuclear cells culture (PBMC) from FOP patients and controls to determine effectiveness of the combination therapy. PBMC were treated with AA, PP and AA+PP combination. Basal expression of 12 of the 22 genes in FOP PBMC was statistically different from controls. ACVR1, ADCY2, ADCY9 and COL3 were downregulated while COL1 was upregulated. ADRB1, ADRB2, RUNX2, TNF-α and ACTB, were all overexpressed in FOP PBMC. In control, AA upregulated COL1, SVCT1, ACTB, AGTR2 and downregulated ADCY2. In FOP cells, AA upregulated ACVR1, BMP4, COL1, COL3, TNF-α, ADCY2, ADCY9, AGTR2 and MAS, while downregulated ADBR2, RUNX2, ADCY1, SVCT1 and ACTB. PP increased ADBR1 and decreased RUNX2, TNF-α, AGTR1, ACTB and CHRNA7 genes in treated control PBMC compared to untreated. PP upregulated ADBR1, ADBR2 and MAS, and downregulated TNF-α and ACTB in treated FOP PBMC versus untreated. AA+PP augmented ADRB1 and ADRB2 expressions in control PBMC. In FOP PBMC, AA+PP augmented ACVR1, COL1, COL3, ADBR1, AGTR2 and MAS expression and downregulated ADBR2, RUNX2, ACTB and MRGD. These data show distinct gene expression modulation in leukocytes from FOP patients when treated with AA and or PP.

3.
Intractable Rare Dis Res ; 8(1): 24-28, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30881854

RESUMO

Fibrodysplasia ossificans progressiva (FOP) is a rare, intractable and devastating genetic connective tissue disorder characterized by progressive ectopic ossification in the soft tissues and skeleton. Three patients, one teenage girl (P1), one male adult (P2) and one male child (P3), were studied and treated with FOPCON (combined formulation of 14 mg of propranolol and 250 mg of ascorbic acid), given three times per day. P1 started treatment in March 2012, P2 in October 2012 and P3 in July 2015. The clinical follow-up of these three patients, before initiating treatment with FOPCON, showed that FOP flare-ups used to occur frequently and that under FOPCON therapy, none of these patients had flare-ups. The striking feature of this treatment with FOPCON, is that, all three cases suffered accidental falls with documented injures until complete healing and that where major flare-ups should occur, injures or sequels, there was none. The present clinical observation shows that ascorbic acid plus the nonspecific beta blocker propranolol can be effectively useful, when administered previously and continually, in the prophylaxis of FOP flare-ups, especially for accidental falls. In this regard, FOPCON could be a prophylactic aid in cases of surgery of patients with FOP, hoping that it may benefit patients from having the severe sequels, characteristic of heterotopic bone formation. All three patients reported, to date, they no longer had flare-ups nor heterotopic ossification and showed normal scar healing.

4.
Biol Sex Differ ; 7: 10, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26848384

RESUMO

BACKGOUND: The male-specific region of chromosome-Y (MSY) contributes to phenotypes outside of testis development and has a high rate of evolution between mammalian species. With a lack of genomic crossover, MSY is one of the few genomic areas under similar variation and evolutionary selection in inbred and outbred animal populations, allowing for an assessment of evolutionary mechanisms to translate between the populations. METHODS: Using next-generation sequencing, MSY consomic strains, molecular characterization, and large-scale phenotyping, we present here regions of MSY that contribute to inbred strain phenotypes. RESULTS: We have shown that (1) MSY of rat has nine autosomal gene transposition events with strain-specific selection; (2) sequence variants in MSY occur with a 1.98-fold higher number of variants than other chromosomes in seven sequenced rat strains; (3) Sry, the most studied MSY gene, has undergone extensive gene duplications, driving ubiquitous expression not seen in human or mouse; (4) the expression profile of Sry in the rat is driven by the insertion of the Sry2 copy into an intron of the ubiquitously expressed Kdm5d gene in antisense orientation, but due to several loss of function mutations in the Sry2 protein, nuclear localization and transcriptional control are decreased; (5) expression of Sry copies other than Sry2 in the rat overlaps with the expression profile for human SRY; (6) gene duplications and sequence variants (P76T) of Sry can be selected for phenotypes such as high blood pressure and androgen receptor signaling within inbred mating; and most importantly, (7) per chromosome size, MSY contributes to higher strain-specific phenotypic variation relative to all other chromosomes, with 53 phenotypes showing both a male to female and consomic cross significance. CONCLUSION: The data presented supports a high probability of MSY genetic variation altering a broad range of inbred rat phenotypes.

5.
Physiol Genomics ; 47(5): 177-86, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25759379

RESUMO

The renin-angiotensin system (RAS) is subject to sex-specific modulation by hormones and gene products. However, sex differences in the balance between the vasoconstrictor/proliferative ACE/ANG II/AT1 axis, and the vasodilator/antiproliferative ACE2/ANG-(1-7)/MAS axis are poorly known. Data in the rat have suggested the male-specific Y-chromosome gene Sry to contribute to balance between these two axes, but why the testis-determining gene has these functions remains unknown. A combination of in silico genetic/protein comparisons, functional luciferase assays for promoters of the human RAS, and RNA-Seq profiling in rat were used to address if regulation of Sry on the RAS is conserved in the homologous X-chromosome gene, Sox3. Both SRY and SOX3 upregulated the promoter of Angiotensinogen (AGT) and downregulated the promoters of ACE2, AT2, and MAS, likely through overlapping mechanisms. The regulation by both SRY and SOX3 on the MAS promoter indicates a cis regulation through multiple SOX binding sites. The Renin (REN) promoter is upregulated by SRY and downregulated by SOX3, likely through trans and cis mechanisms, respectively. Sry transcripts are found in all analyzed male rat tissues including the kidney, while Sox3 transcripts are found only in the brain and testis, suggesting that the primary tissue for renin production (kidney) can only be regulated by SRY and not SOX3. These results suggest that SRY regulation of the RAS is partially shared with its X-chromosome homolog SOX3, but SRY gained a sex-specific control in the kidney for the rate-limiting step of the RAS, potentially resulting in male-specific blood pressure regulation.


Assuntos
Regulação da Expressão Gênica , Regiões Promotoras Genéticas , Sistema Renina-Angiotensina/genética , Fatores de Transcrição SOXB1/genética , Proteína da Região Y Determinante do Sexo/genética , Cromossomo X/genética , Cromossomo Y/genética , Sequência de Aminoácidos , Angiotensinogênio/genética , Animais , Sequência de Bases , Sítios de Ligação , Células CHO , Sequência Conservada , Cricetinae , Cricetulus , Feminino , Perfilação da Expressão Gênica , Humanos , Luciferases/metabolismo , Masculino , Dados de Sequência Molecular , Peptidil Dipeptidase A/genética , Renina/genética , Fatores de Transcrição SOXB1/química , Fatores de Transcrição SOXB1/metabolismo , Homologia de Sequência do Ácido Nucleico , Proteína da Região Y Determinante do Sexo/química , Proteína da Região Y Determinante do Sexo/metabolismo
6.
Int J Mol Sci ; 16(3): 4392-415, 2015 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-25706513

RESUMO

There has been an intense research effort in the last decades in the field of biofouling prevention as it concerns many aspects of everyday life and causes problems to devices, the environment, and human health. Many different antifouling and antimicrobial materials have been developed to struggle against bacteria and other micro- and macro-organism attachment to different surfaces. However the "miracle solution" has still to be found. The research presented here concerns the synthesis of bio-based polymeric materials and the biological tests that showed their antifouling and, at the same time, antibacterial activity. The raw material used for the coating synthesis was natural rubber. The polyisoprene chains were fragmented to obtain oligomers, which had reactive chemical groups at their chain ends, therefore they could be modified to insert polymerizable and biocidal groups. Films were obtained by radical photopolymerization of the natural rubber derived oligomers and their structure was altered, in order to understand the mechanism of attachment inhibition and to increase the efficiency of the anti-biofouling action. The adhesion of three species of pathogenic bacteria and six strains of marine bacteria was studied. The coatings were able to inhibit bacterial attachment by contact, as it was verified that no detectable leaching of toxic molecules occurred.


Assuntos
Anti-Infecciosos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Butadienos/farmacologia , Hemiterpenos/farmacologia , Pentanos/farmacologia , Polímeros/farmacologia , Anti-Infecciosos/química , Aderência Bacteriana/fisiologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Butadienos/química , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/fisiologia , Hemiterpenos/química , Espectroscopia de Ressonância Magnética , Microscopia de Força Atômica , Estrutura Molecular , Pentanos/química , Polímeros/química , Água do Mar/microbiologia , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
7.
Gen Comp Endocrinol ; 215: 106-16, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25260253

RESUMO

The details of protein pathways at a structural level provides a bridge between genetics/molecular biology and physiology. The renin-angiotensin system is involved in many physiological pathways with informative structural details in multiple components. Few studies have been performed assessing structural knowledge across the system. This assessment allows use of bioinformatics tools to fill in missing structural voids. In this paper we detail known structures of the renin-angiotensin system and use computational approaches to estimate and model components that do not have their protein structures defined. With the subsequent large library of protein structures, we then created a species specific protein library for human, mouse, rat, bovine, zebrafish, and chicken for the system. The rat structural system allowed for rapid screening of genetic variants from 51 commonly used rat strains, identifying amino acid variants in angiotensinogen, ACE2, and AT1b that are in contact positions with other macromolecules. We believe the structural map will be of value for other researchers to understand their experimental data in the context of an environment for multiple proteins, providing pdb files of proteins for the renin-angiotensin system in six species. With detailed structural descriptions of each protein, it is easier to assess a species for use in translating human diseases with animal models. Additionally, as whole genome sequencing continues to decrease in cost, tools such as molecular modeling will gain use as an initial step in designing efficient hypothesis driven research, addressing potential functional outcomes of genetic variants with precompiled protein libraries aiding in rapid characterizations.


Assuntos
Angiotensinogênio/química , Evolução Biológica , Biologia Computacional , Modelos Moleculares , Sistema Renina-Angiotensina , Renina/química , Sequência de Aminoácidos , Angiotensinogênio/metabolismo , Animais , Bovinos , Galinhas , Humanos , Camundongos , Dados de Sequência Molecular , Conformação Proteica , Ratos , Renina/metabolismo , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Peixe-Zebra
8.
PLoS One ; 9(3): e92751, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24663438

RESUMO

Leptin is a pleiotropic protein best known for regulation of appetite and fat storage in mammals. While many leptin orthologs have been identified among vertebrates, an authentic leptin in birds has remained elusive and controversial. Here we identify leptin sequence from the Peregrine falcon, Falco peregrinus (pfleptin), and identify sequences from two other birds (mallard and zebra finch), and 'missing' vertebrates (elephant shark, alligator, Indian python, Chinese soft-shelled turtle, and coelacanth). The pattern of genes surrounding leptin (snd1, rbm28) is syntenic between the falcon and mammalian genomes. Phylogenetic analysis of all known leptin protein sequences improves our understanding of leptin's evolution. Structural modeling of leptin orthologs highlights a highly conserved hydrophobic core in the four-helix cytokine packing domain. A docked model of leptin with the leptin receptor for Peregrine falcon reveals several conserved amino acids important for the interaction and possible coevolution of leptin with its receptor. We also show for the first time, an authentic avian leptin sequence that activates the JAK-STAT signaling pathway. These newly identified sequences, structures, and tools for avian leptin and its receptor will allow elucidation of the function of these proteins in feral and domestic birds.


Assuntos
Aves/genética , Evolução Molecular , Leptina , Modelos Moleculares , Filogenia , Receptores para Leptina , Animais , Leptina/química , Leptina/genética , Receptores para Leptina/química , Receptores para Leptina/genética , Répteis/genética , Análise de Sequência de Proteína
9.
Math Med Biol ; 31(2): 179-204, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23518337

RESUMO

Lung failure due to chronic bacterial infection is the leading cause of death for patients with cystic fibrosis (CF). It is thought that the chronic nature of these infections is, in part, due to the increased tolerance and recalcitrant behaviour of bacteria growing as biofilms. Inhalation of silver carbene complex (SCC) antimicrobial, either encased in polymeric biodegradable particles or in aqueous form, has been proposed as a treatment. Through a coordinated experimental and mathematical modelling effort, we examine this proposed treatment of lung biofilms. Pseudomonas aeruginosa biofilms grown in a flow-cell apparatus irrigated with an artificial CF sputum medium are analysed as an in vitro model of CF lung infection. A 2D mathematical model of biofilm growth within the flow-cell is developed. Numerical simulations demonstrate that SCC inactivation by the environment is critical in aqueous SCC, but not SCC-polymer, based treatments. Polymer particle degradation rate is shown to be an important parameter that can be chosen optimally, based on environmental conditions and bacterial susceptibility.


Assuntos
Biofilmes/crescimento & desenvolvimento , Fibrose Cística/complicações , Modelos Imunológicos , Infecções por Pseudomonas/complicações , Pseudomonas aeruginosa/crescimento & desenvolvimento , Prata/farmacologia , Biofilmes/efeitos dos fármacos , Simulação por Computador , Fibrose Cística/imunologia , Humanos , Técnicas In Vitro , Microscopia Confocal , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa/ultraestrutura , Prata/administração & dosagem , Escarro/microbiologia
10.
Clin Sci (Lond) ; 126(10): 727-38, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24128372

RESUMO

The ACE2 (angiotensin-converting enzyme 2)/Ang-(1-7) [angiotensin-(1-7)]/MAS axis of the RAS (renin-angiotensin system) has emerged as a pathway of interest in treating both cardiovascular disorders and cancer. The MAS protein is known to bind to and be activated by Ang-(1-7); however, the mechanisms of this activation are just starting to be understood. Although there are strong biochemical data regarding the regulation and activation of the AT1R (angiotensin II type 1 receptor) and the AT2R (angiotensin II type 2 receptor), with models of how AngII (angiotensin II) binds each receptor, fewer studies have characterized MAS. In the present study, we characterize the MAS promoter and provide a potential feedback mechanism that could compensate for MAS degradation following activation by Ang-(1-7). Analysis of ENCODE data for the MAS promoter revealed potential epigenetic control by KRAB (Krüppel-associated box)/KAP-1 (KRAB-associated protein-1). A proximal promoter construct for the MAS gene was repressed by the SOX [SRY (sex-determining region on the Y chromosome) box] proteins SRY, SOX2, SOX3 and SOX14, of which SRY is known to interact with the KRAB domain. The KRAB-KAP-1 complex can be tyrosine-nitrated, causing the dissociation of the KAP-1 protein and thus a potential loss of epigenetic control. Activation of MAS can lead to an increase in nitric oxide, suggesting a feedback mechanism for MAS on its own promoter. The results of the present study provide a more complete view of MAS regulation and, for the first time, suggest biochemical outcomes for nitration of the KRAB domain.


Assuntos
Retroalimentação Fisiológica , Regulação da Expressão Gênica , Fatores de Transcrição Kruppel-Like/química , Fatores de Transcrição Kruppel-Like/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/genética , Receptores Acoplados a Proteínas G/genética , Tirosina/metabolismo , Animais , Humanos , Modelos Biológicos , Modelos Moleculares , Óxido Nítrico/metabolismo , Nitrosação , Ligação Proteica/genética , Estrutura Terciária de Proteína , Proto-Oncogene Mas , Proteína da Região Y Determinante do Sexo
11.
BMC Genomics ; 14: 792, 2013 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-24228692

RESUMO

BACKGROUND: Gene copy number variation plays a large role in the evolution of genomes. In Rattus norvegicus and other rodent species, the Y-chromosome has accumulated multiple copies of Sry loci. These copy number variations have been previously linked with changes in phenotype of animal models such as the spontaneously hypertensive rat (SHR). This study characterizes the Y-chromosome in the Sry region of Rattus norvegicus, while addressing functional variations seen in the Sry protein products. RESULTS: Eleven Sry loci have been identified in the SHR with one (nonHMG Sry) containing a frame shift mutation. The nonHMGSry is found and conserved in the related WKY and SD rat strains. Three new, previously unidentified, Sry loci were identified in this study (Sry3BII, Sry4 and Sry4A) in both SHR and WKY. Repetitive element analysis revealed numerous LINE-L1 elements at regions where conservation is lost among the Sry copies. In addition we have identified a retrotransposed copy of Med14 originating from spliced mRNA, two autosomal genes (Ccdc110 and HMGB1) and a normal mammalian Y-chromosome gene (Zfy) in the Sry region of the rat Y-chromosome. Translation of the sequences of each Sry gene reveals eight proteins with amino acid differences leading to changes in nuclear localization and promoter activation of a Sry-responsive gene. Sry-ß (coded by the Sry2 locus) has an increased cytoplasmic fraction due to alterations at amino acid 21. Sry-γ has altered gene regulation of the Sry1 promoter due to changes at amino acid 76. CONCLUSIONS: The duplication of Sry on the Rattus norvegicus Y-chromosome has led to proteins with altered functional ability that may have been selected for functions in addition to testis determination. Additionally, several other genes not normally found on the Y-chromosome have duplicated new copies into the region around the Sry genes. These suggest a role of active transposable elements in the evolution of the mammalian Y-chromosome in species such as Rattus norvegicus.


Assuntos
Variações do Número de Cópias de DNA/genética , Proteína da Região Y Determinante do Sexo/genética , Cromossomo Y/genética , Animais , Sequência de Bases , Proteínas de Ligação a DNA , Regulação da Expressão Gênica , Humanos , Masculino , Ratos , Ratos Endogâmicos SHR , Proteína da Região Y Determinante do Sexo/biossíntese , Testículo/metabolismo
12.
Biochem Biophys Res Commun ; 438(4): 691-6, 2013 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-23921230

RESUMO

In the medical field, attached bacteria can cause infections associated with catheters, incisions, burns, and medical implants especially in immunocompromised patients. The problem is exacerbated by the fact that attached bacteria are ∼1000 times more resistant to antibiotics than planktonic cells. The rapid spread of antibiotic resistance in these and other organisms has led to a significant need to find new methods for preventing bacterial attachment. The goal of this research was to evaluate the effectiveness of novel polymer coatings to prevent the attachment of three medically relevant bacteria. Tests were conducted with Pseudomonas aeruginosa, Staphylococcus epidermidis, and Staphylococcus aureus for oligomers derived from modifications of natural rubber (cis 1,4-polyisoprene). The different oligomers were: PP04, with no quaternary ammonium (QA); MV067, one QA; PP06, three QA groups. In almost all experiments, cell attachment was inhibited to various extents as long as the oligomers were used. PP06 was the most effective as it decreased the planktonic cell numbers by at least 50% for all bacteria. Differences between species sensitivity were also observed. P. aeruginosa was the most resistant bacteria tested, S. aureus, the most sensitive. Further experiments are required to understand the full extent and mode of the antimicrobial properties of these surfaces.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Borracha/química , Borracha/farmacologia , Staphylococcus/efeitos dos fármacos , Hemiterpenos/química , Hemiterpenos/farmacologia , Humanos , Látex/química , Látex/farmacologia , Infecções por Pseudomonas/prevenção & controle , Pseudomonas aeruginosa/fisiologia , Infecções Estafilocócicas/prevenção & controle , Staphylococcus/fisiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/fisiologia
13.
PLoS One ; 8(6): e65307, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23755216

RESUMO

The renin-angiotensin system is involved in multiple conditions ranging from cardiovascular disorders to cancer. Components of the pathway, including ACE, renin and angiotensin receptors are targets for disease treatment. This study addresses three receptors of the pathway: AT1, AT2, and MAS and how the receptors are similar and differ in activation by angiotensin peptides. Combining biochemical and amino acid variation data with multiple species sequence alignments, structural models, and docking site predictions allows for visualization of how angiotensin peptides may bind and activate the receptors; allowing identification of conserved and variant mechanisms in the receptors. MAS differs from AT1 favoring Ang-(1-7) and not Ang II binding, while AT2 recently has been suggested to preferentially bind Ang III. A new model of Ang peptide binding to AT1 and AT2 is proposed that correlates data from site directed mutagenesis and photolabled experiments that were previously considered conflicting. Ang II binds AT1 and AT2 through a conserved initial binding mode involving amino acids 111 (consensus 325) of AT1 (Asn) interacting with Tyr (4) of Ang II and 199 and 256 (consensus 512 and 621, a Lys and His respectively) interacting with Phe (8) of Ang II. In MAS these sites are not conserved, leading to differential binding and activation by Ang-(1-7). In both AT1 and AT2, the Ang II peptide may internalize through Phe (8) of Ang II propagating through the receptors' conserved aromatic amino acids to the final photolabled positioning relative to either AT1 (amino acid 294, Asn, consensus 725) or AT2 (138, Leu, consensus 336). Understanding receptor activation provides valuable information for drug design and identification of other receptors that can potentially bind Ang peptides.


Assuntos
Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Proteínas Proto-Oncogênicas/química , Receptor Tipo 1 de Angiotensina/química , Receptor Tipo 2 de Angiotensina/química , Receptores Acoplados a Proteínas G/química , Sequência de Aminoácidos , Angiotensina I/química , Angiotensina II/química , Angiotensina III/química , Humanos , Dados de Sequência Molecular , Peptídeos/química , Peptidil Dipeptidase A/química , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Transporte Proteico , Proto-Oncogene Mas , Renina/química , Alinhamento de Sequência , Homologia Estrutural de Proteína
14.
J Mol Model ; 19(9): 3463-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23708613

RESUMO

Binding of transcription factors to DNA is a dynamic process allowing for spatial- and sequence-specificity. Many methods for determination of DNA-protein structures do not allow for identification of dynamics of the search process, but provide only a single snapshot of the most stable binding. In order to better understand the dynamics of DNA binding as a protein encounters its cognate site, we have created a computer-based DNA scanning array macro that sequentially inserts a high affinity DNA consensus binding site at all possible locations in a predicted protein-DNA interface. We show, using short molecular dynamic simulations at each location in the interface, that energy minimized states and decreased movement of evolutionary conserved amino acids can be readily observed and used to predict the consensus binding site. The macro was applied to SNAIL class C2H2 zinc finger family proteins. The analysis suggests that (1) SNAIL binds to the E-box in multiple states during its encounter with its cognate site; (2) several different amino acids contribute to the E-box binding in each state; (3) the linear array of zinc fingers contributes differentially to overall folding and base-pair recognition; and (4) each finger may be specialized for stability and sequence specificity. Moreover, the macromolecular movement observed using this dynamic approach may allow the NH2-terminal finger to bind without sequence specificity yet result in higher binding energy. This macro and overall approach could be applicable to many evolutionary conserved transcription factor families and should help to better elucidate the varied mechanisms used for DNA sequence-specific binding.


Assuntos
DNA/química , Elementos E-Box , Simulação de Dinâmica Molecular , Fatores de Transcrição/química , Sequência de Aminoácidos , Sítios de Ligação , Simulação por Computador , DNA/genética , DNA/metabolismo , Conformação Molecular , Simulação de Acoplamento Molecular , Dados de Sequência Molecular , Ligação Proteica , Fatores de Transcrição da Família Snail , Fatores de Transcrição/metabolismo , Dedos de Zinco
15.
J Theor Biol ; 308: 68-78, 2012 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-22677397

RESUMO

We present a mathematical model of mushroom-like architecture and cavity formation in Pseudomonas aeruginosa biofilms. We demonstrate that a proposed disparity in internal friction between the stalk and cap extracellular polymeric substances (EPS) leads to spatial variation in volumetric expansion sufficient to produce the mushroom morphology. The capability of diffusible signals to induce the formation of a fluid-filled cavity within the cap is then investigated. We assume that conversion of bacteria to the planktonic state within the cap occurs in response to the accumulation or depletion of some signal molecule. We (a) show that neither simple nutrient starvation nor signal production by one or more subpopulations of bacteria is sufficient to trigger localized cavity formation. We then (b) demonstrate various hypothetical scenarios that could result in localized cavity formation. Finally, we (c) model iron availability as a detachment signal and show simulation results demonstrating cavity formation by iron starvation. We conclude that iron availability is a plausible mechanism by which fluid-filled cavities form in the cap region of mushroom-like structures.


Assuntos
Biofilmes/crescimento & desenvolvimento , Deficiências de Ferro , Modelos Biológicos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/fisiologia , Biofilmes/efeitos dos fármacos , Simulação por Computador , Oligopeptídeos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
16.
BMC Bioinformatics ; 13 Suppl 2: S3, 2012 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-22536866

RESUMO

BACKGROUND: The DNA binding domain of HMG proteins is known to be important in many diseases, with the Sox sub-family of HMG proteins of particular significance. Numerous natural variants in HMG proteins are associated with disease phenotypes. Integrating these natural variants, molecular dynamic simulations of DNA interaction and sequence and structure alignments give detailed molecular knowledge of potential amino acid function such as DNA or protein interaction. RESULTS: A total of 33 amino acids in HMG proteins are known to have natural variants in diseases. Eight of these amino acids are normally conserved in human HMG proteins and 27 are conserved in the human Sox sub-family. Among the six non-Sox conserved amino acids, amino acids 16 and 45 are likely targets for interaction with other proteins. Docking studies between the androgen receptor and Sry/Sox9 reveals a stable amino acid specific interaction involving several Sox conserved residues. CONCLUSION: The HMG box has structural conservation between the first two of the three helixes in the domain as well as some DNA contact points. Individual sub-groups of the HMG family have specificity in the location of the third helix, DNA specific contact points (such as amino acids 4 and 29), and conserved amino acids interacting with other proteins such as androgen receptor. Studies such as this help to distinguish individual members of a much larger family of proteins and can be applied to any protein family of interest.


Assuntos
Aminoácidos/química , Domínios HMG-Box , Proteínas de Grupo de Alta Mobilidade/química , Simulação de Dinâmica Molecular , DNA/química , DNA/metabolismo , Doença/genética , Variação Genética , Proteínas de Grupo de Alta Mobilidade/genética , Proteínas de Grupo de Alta Mobilidade/metabolismo , Humanos , Estrutura Secundária de Proteína , Alinhamento de Sequência , Análise de Sequência de Proteína , Homologia Estrutural de Proteína
17.
Int J Hypertens ; 2012: 724240, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22315667

RESUMO

The testis determining protein, Sry, has functions outside of testis determination. Multiple Sry loci are found on the Y-chromosome. Proteins from these loci have differential activity on promoters of renin-angiotensin system genes, possibly contributing to elevation of blood pressure. Variation at amino acid 76 accounts for the majority of differential effects by rat proteins Sry1 and Sry3. Human SRY regulated rat promoters in the same manner as rat Sry, elevating Agt, Ren, and Ace promoter activity while downregulating Ace 2. Human SRY significantly regulated human promoters of AGT, REN, ACE2, AT2, and MAS compared to control levels, elevating AGT and REN promoter activity while decreasing ACE2, AT2, and MAS. While the effect of human SRY on individual genes is often modest, we show that many different genes participating in the renin-angiotensin system can be affected by SRY, apparently in coordinated fashion, to produce more Ang II and less Ang-(1-7).

18.
Virol J ; 8: 334, 2011 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-21718481

RESUMO

Apoptosis can be induced or inhibited by viral proteins, it can form part of the host defense against virus infection, or it can be a mechanism for viral spread to neighboring cells. Canine distemper virus (CDV) induces apoptotic cells in lymphoid tissues and in the cerebellum of dogs naturally infected. CDV also produces a cytopathologic effect, leading to apoptosis in Vero cells in tissue culture. We tested canine distemper virus, a member of the Paramyxoviridae family, for the ability to trigger apoptosis in HeLa cells, derived from cervical cancer cells resistant to apoptosis. To study the effect of CDV infection in HeLa cells, we examined apoptotic markers 24 h post infection (pi), by flow cytometry assay for DNA fragmentation, real-time PCR assay for caspase-3 and caspase-8 mRNA expression, and by caspase-3 and -8 immunocytochemistry. Flow cytometry showed that DNA fragmentation was induced in HeLa cells infected by CDV, and immunocytochemistry revealed a significant increase in the levels of the cleaved active form of caspase-3 protein, but did not show any difference in expression of caspase-8, indicating an intrinsic apoptotic pathway. Confirming this observation, expression of caspase-3 mRNA was higher in CDV infected HeLa cells than control cells; however, there was no statistically significant change in caspase-8 mRNA expression profile. Our data suggest that canine distemper virus induced apoptosis in HeLa cells, triggering apoptosis by the intrinsic pathway, with no participation of the initiator caspase -8 from the extrinsic pathway. In conclusion, the cellular stress caused by CDV infection of HeLa cells, leading to apoptosis, can be used as a tool in future research for cervical cancer treatment and control.


Assuntos
Apoptose , Vírus da Cinomose Canina/patogenicidade , Vírus Oncolíticos/patogenicidade , Caspase 3/biossíntese , Caspase 8/biossíntese , Fragmentação do DNA , Citometria de Fluxo , Perfilação da Expressão Gênica , Células HeLa , Humanos , Imuno-Histoquímica
19.
Am J Physiol Regul Integr Comp Physiol ; 301(3): R561-71, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21677270

RESUMO

The Sry locus on the mammalian Y chromosome is the developmental switch responsible for testis determination. Inconsistent with this important function, the Sry locus is transcribed in adult males at times and in tissues not involved with testis determination. Sry is expressed in multiple tissues of the peripheral and central nervous system. Sry is derived from Sox3 and is similar to other SOXB family loci. The SOXB loci are responsible for nervous system development. Sry has been demonstrated to modulate the catecholamine pathway, so it should have functional consequences in the central and peripheral nervous system. The nervous system expression and potential function are consistent with Sry as a SOXB family member. In mammals, Sox3 is X-linked and undergoes dosage compensation in females. The expression of Sry in adult males allows for a type of sexual differentiation independent of circulating gonadal hormones. A quantitative difference in Sox3 plus Sry expression in males vs. females could drive changes in the transcriptome of these cells, differentiating male and female cells. Sry expression and its transcriptional effects should be considered when investigating sexual dimorphic phenotypes.


Assuntos
Proteína da Região Y Determinante do Sexo/metabolismo , Transdução de Sinais , Testículo/metabolismo , Cromossomo Y , Animais , Feminino , Regulação da Expressão Gênica , Genótipo , Humanos , Masculino , Sistema Nervoso/metabolismo , Sistemas Neurossecretores/metabolismo , Organogênese , Fenótipo , Conformação Proteica , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Caracteres Sexuais , Processos de Determinação Sexual , Proteína da Região Y Determinante do Sexo/química , Proteína da Região Y Determinante do Sexo/genética , Testículo/embriologia
20.
Gend Med ; 8(2): 126-38, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21536231

RESUMO

BACKGROUND: Sex-determining region Y (Sry) is a transcription factor. Our research group has shown that there are multiple copies of Sry in Wistar-Kyoto (WKY) and spontaneous hypertensive (SHR) rats, and that they have novel functions separate from testes determination. OBJECTIVE: We hypothesized that exogenously delivered Sry3 to the normotensive WKY male kidney would activate the renin-angiotensin system (RAS) and raise blood pressure (BP), based on previous in vitro studies. METHODS: Sry3 or control vector was electroporated to the left kidney of male WKY rats and the following measurements were taken: BP by telemetry, renin-angiotensin measures by radioimmunoassay, plasma and tissue catecholamines by HPLC with electrochemical detection, sodium by flame photometry, and inulin by ELISA. RESULTS: Sry3 increased BP 10 to 20 mm Hg compared with controls (P < 0.01) and produced a significant 40% decrease in urine sodium compared with controls (P < 0.05). Sry3 increased renal angiotensin II and plasma renin activity by >100% compared with controls (P < 0.01 and P < 0.05, respectively). CONCLUSION: The findings presented here confirm and extend the argument for Sry3 as one of the genes responsible for the SHR hypertensive Y chromosome phenotype and are consistent with increased tissue RAS activity due to Sry3 and increased sodium reabsorption.


Assuntos
Pressão Sanguínea/genética , Hipertensão/genética , Rim/metabolismo , Sistema Renina-Angiotensina/genética , Cromossomo Y/genética , Análise de Variância , Animais , Pressão Sanguínea/fisiologia , Catecolaminas/metabolismo , Cromatografia Líquida de Alta Pressão , Creatinina/metabolismo , Eletroforese , Ensaio de Imunoadsorção Enzimática , Marcadores Genéticos , Taxa de Filtração Glomerular , Indicadores Básicos de Saúde , Masculino , Ratos , Ratos Endogâmicos WKY , Sistema Renina-Angiotensina/fisiologia , Fatores de Risco , Proteína da Região Y Determinante do Sexo/genética , Proteína da Região Y Determinante do Sexo/metabolismo , Cromossomo Y/metabolismo
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