23 research outputs found
CpG methylation at GATA elements in the regulatory region of CCR3 positively correlates with CCR3 transcription
DNA methylation may regulate gene expression by restricting the access of transcription factors. We have previously demonstrated that GATA-1 regulates the transcription of the CCR3 gene by dynamically interacting with both positively and negatively acting GATA elements of high affinity binding in the proximal promoter region including exon 1. Exon 1 has three CpG sites, two of which are positioned at the negatively acting GATA elements. We hypothesized that the methylation of these two CpGs sites might preclude GATA-1 binding to the negatively acting GATA elements and, as a result, increase the availability of GATA-1 to the positively acting GATA element, thereby contributing to an increase in GATA-1-mediated transcription of the gene. To this end, we determined the methylation of the three CpG sites by bisulfate pyrosequencing in peripheral blood eosinophils, cord blood (CB)-derived eosinophils, PBMCs, and cell lines that vary in CCR3 mRNA expression. Our results demonstrated that methylation of CpG sites at the negatively acting GATA elements severely reduced GATA-1 binding and augmented transcription activity in vitro. In agreement, methylation of these CpG sites positively correlated with CCR3 mRNA expression in the primary cells and cell lines examined. Interestingly, methylation patterns of these three CpG sites in CB-derived eosinophils mostly resembled those in peripheral blood eosinophils. These results suggest that methylation of CpG sites at the GATA elements in the regulatory regions fine-tunes CCR3 transcription
Physical characterisation of an alginate/lysozyme nano-laminate coating and its evaluation on âcoalhoâ cheese shelf life
This work aimed at the characterisation of a nanolaminate
coating produced by the layer-by-layer methodology
and its evaluation on the preservation of âCoalhoâ cheese.
Initially, five alternate layers of alginate and lysozyme were
assembled in an aminolysed/charged polyethylene terephthalate
(A/C PET) and physically characterised by UV/VIS
spectroscopy, contact angle, water vapour (WVTR) and oxygen
(OTR) transmission rates and scanning electron microscopy.
Afterwards, the same methodology was used to
apply the nano-laminate coating in âCoalhoâ cheese and its
shelf life was evaluated during 20 days in terms of mass
loss, pH, lipid peroxidation, titratable acidity and microbial
count. UV/VIS spectroscopy and contact angle analyses
confirmed the layersâ deposition and the successful assembly
of nano-laminate coating on A/C PET surface. The coating
presented WVTR and OTR values of 1.03Ă10â3 and 1.28Ă
10â4 g mâ2 sâ1, respectively. After 20 days, coated cheese
showed lower values of mass loss, pH, lipidic peroxidation,
microorganismsâ proliferation and higher titratable acidity in
comparison with uncoated cheese. These results suggest that
gas barrier and antibacterial properties of alginate/lysozyme
nanocoating can be used to extend the shelf life of âCoalhoâ
cheese.The author Bartolomeu G. de S. Medeiros is recipient of a scholarship from Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES-Brazil). The author Marthyna P. Souza is recipient of a scholarship from Fundacao de Amparo a Ciencia e Tecnologia do Estado de Pernambuco (FACEPE, Brazil) and was recipient of a scholarship from Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES/PDEE-Brazil). The authors Ana C. Pinheiro, Ana I. Bourbon and Miguel A. Cerqueira are recipients of a fellowship (SFRH/BD/48120/2008, SFRH/BD/73178/2010 and SFRH/BPD/72753/2010, respectively), supported by Fundacao para a Ciencia e Tecnologia, POPH-QREN and FSE (FCT, Portugal). Maria G. Carneiro-da-Cunha express is gratitude to the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) for research grant. The present work was supported by CAPES/PROCAD/NF/1415/2007. The support of EU Cost Action FA0904 is gratefully acknowledged
Physical and Functional Interaction between 5-HT6 Receptor and Nova-1
5-HT6 receptor (5-HT6R) is implicated in cognitive dysfunction, mood disorder, psychosis, and eating disorders. However, despite its significant role in regulating the brain functions, regulation of 5-HT6R at the molecular level is poorly understood. Here, using yeast two-hybrid assay, we found that human 5-HT6R directly binds to neuro-oncological ventral antigen 1 (Nova-1), a brain-enriched splicing regulator. The interaction between 5-HT6R and Nova-1 was confirmed using GST pull-down and co-immunoprecipitation assays in cell lines and rat brain. The splicing activity of Nova-1 was decreased upon overexpression of 5-HT6R, which was examined by detecting the spliced intermediates of gonadotropin-releasing hormone (GnRH), a known pre-mRNA target of Nova-1, using RT-PCR. In addition, overexpression of 5-HT6R induced the translocation of Nova-1 from the nucleus to cytoplasm, resulting in the reduced splicing activity of Nova-1. In contrast, overexpression of Nova-1 reduced the activity and the total protein levels of 5-HT6R. Taken together, these results indicate that when the expression levels of 5-HT6R or Nova-1 protein are not properly regulated, it may also deteriorate the function of the other. Copyright © Experimental Neurobiology 2019.1
Synthesis and in Vitro Study of Antibacterial, Antifungal Activities of some Novel Bisquinolines
Efficient syntheses of a series of novel bisquinolines
have been accomplished from8-hydroxy quinolines under
phase transfer catalyzed conditions using tetrabutylamoniumbromide
as phase transfer catalyst. In vitro antibacterial and antifungal
study of the synthesized analogues revealed six of them to
show significant antibacterial and four to show significant antifungal
activity. Among them 3c and 6c show most significant
antibacterial activities with minimum inhibitory concentration
value 32 lg/mL against four bacterial strains. Ultra structural
studies of the microbes treated with 6c demonstrated deformation
of cell wall and cell agglomeration. The bisquinolines
exhibiting bacteriostatic or fungistatic activity may be developed
as newer antimicrobial agents