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1.
Polymers (Basel) ; 16(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38611192

RESUMO

In the process of paper recycling, certain amounts of metals can be found in the cellulose suspension, the source of which is mainly printing inks. The paper industry often uses different technologies to reduce heavy metal emissions. The recycling of laminated packaging contributes to the formation of sticky particles, which affects the concentration of heavy metals. This study aimed to determine the mass fraction of metals in the different phases of the deinking process to optimize the cellulose pulp's quality and design healthy correct packaging products. In this research, the deinking flotation of laminated and non-laminated samples was carried out by the Ingede 11 method. As a result of the study, the mass fractions of metals in cellulose pulp were divided into four groups according to the mass fraction's increasing value and the metals' increasing electronegativity. The quantities of metals were analyzed using Inductively Coupled Mass Spectrometry (ICP-MS). The separation of metals from cellulose pulp is influenced by the presence of adhesives and the electronegativity of the metal. The results of the study show that the recycling process removes certain heavy metals very well, which indicates the good recycling potential of pharmaceutical cardboard samples.

2.
PLoS Genet ; 14(5): e1007391, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29758044

RESUMO

Planar cell polarity (PCP) instructs tissue patterning in a wide range of organisms from fruit flies to humans. PCP signaling coordinates cell behavior across tissues and is integrated by cells to couple cell fate identity with position in a developing tissue. In the fly eye, PCP signaling is required for the specification of R3 and R4 photoreceptors based upon their positioning relative to the dorso-ventral axis. The 'core' PCP pathway involves the asymmetric localization of two distinct membrane-bound complexes, one containing Frizzled (Fz, required in R3) and the other Van Gogh (Vang, required in R4). Inhibitory interactions between the cytosolic components of each complex reinforce asymmetric localization. Prickle (Pk) and Spiny-legs (Pk-Sple) are two antagonistic isoforms of the prickle (pk) gene and are cytoplasmic components of the Vang complex. The balance between their levels is critical for tissue patterning, with Pk-Sple being the major functional isoform in the eye. Here we uncover a post-translational role for Nemo kinase in limiting the amount of the minor isoform Pk. We identified Pk as a Nemo substrate in a genome-wide in vitro band-shift screen. In vivo, nemo genetically interacts with pkpk but not pksple and enhances PCP defects in the eye and leg. Nemo phosphorylation limits Pk levels and is required specifically in the R4 photoreceptor like the major isoform, Pk-Sple. Genetic interaction and biochemical data suggest that Nemo phosphorylation of Pk leads to its proteasomal degradation via the Cullin1/SkpA/Slmb complex. dTAK and Homeodomain interacting protein kinase (Hipk) may also act together with Nemo to target Pk for degradation, consistent with similar observations in mammalian studies. Our results therefore demonstrate a mechanism to maintain low levels of the minor Pk isoform, allowing PCP complexes to form correctly and specify cell fate.


Assuntos
Polaridade Celular/genética , Proteínas de Ligação a DNA/genética , Proteínas de Drosophila/genética , Proteínas com Domínio LIM/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Animais , Animais Geneticamente Modificados , Linhagem Celular , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Olho/citologia , Olho/metabolismo , Receptores Frizzled/genética , Receptores Frizzled/metabolismo , Proteínas com Domínio LIM/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteólise , Transdução de Sinais/genética , Especificidade por Substrato , Asas de Animais/citologia , Asas de Animais/metabolismo
3.
Biol Open ; 1(5): 498-505, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23213442

RESUMO

In addition to their ubiquitous apical-basal polarity, many epithelia are also polarized along an orthogonal axis, a phenomenon termed planar cell polarity (PCP). In the mammalian inner ear and the zebrafish lateral line, PCP is revealed through the orientation of mechanosensitive hair cells relative to each other and to the body axes. In each neuromast, the receptor organ of the lateral line, hair bundles are arranged in a mirror-symmetrical fashion. Here we show that the establishment of mirror symmetry is preceded by rotational rearrangements between hair-cell pairs, a behavior consistently associated with the division of hair-cell precursors. Time-lapse imaging of trilobite mutants, which lack the core PCP constituent Vang-like protein 2 (Vangl2), shows that their misoriented hair cells correlate with misaligned divisions of hair-cell precursors and an inability to complete rearrangements accurately. Vangl2 is asymmetrically localized in the cells of the neuromast, a configuration required for accurate completion of rearrangements. Manipulation of Vangl2 expression or of Notch signaling results in a uniform hair-cell polarity, indicating that rearrangements refine neuromast polarity with respect to the body axes.

4.
Nat Struct Mol Biol ; 18(6): 665-72, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21552260

RESUMO

Frizzled planar cell polarity (PCP) signaling regulates cell motility in several tissues, including ommatidial rotation in Drosophila melanogaster. The Nemo kinase (Nlk in vertebrates) has also been linked to cell-motility regulation and ommatidial rotation but its mechanistic role(s) during rotation remain obscure. We show that nemo functions throughout the entire rotation movement, increasing the rotation rate. Genetic and molecular studies indicate that Nemo binds both the core PCP factor complex of Strabismus-Prickle, as well as the E-cadherin-ß-catenin (E-cadherin-Armadillo in Drosophila) complex. These two complexes colocalize and, like Nemo, also promote rotation. Strabismus (also called Vang) binds and stabilizes Nemo asymmetrically within the ommatidial precluster; Nemo and ß-catenin then act synergistically to promote rotation, which is mediated in vivo by Nemo's phosphorylation of ß-catenin. Our data suggest that Nemo serves as a conserved molecular link between core PCP factors and E-cadherin-ß-catenin complexes, promoting cell motility.


Assuntos
Caderinas/metabolismo , Movimento Celular , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , beta Catenina/metabolismo , Animais , Drosophila melanogaster/fisiologia , Proteínas com Domínio LIM , Fenômenos Fisiológicos Oculares , Fosforilação , Ligação Proteica
5.
Mech Dev ; 125(1-2): 30-42, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18065209

RESUMO

Members of the Frizzled (Fz) family of seven-pass transmembrane receptors are required for the transduction of both Wnt-Fz/beta-catenin and Fz/planar cell polarity (PCP) signals. Although both pathways transduce signals via interactions between Fz and the cytoplasmic protein Dishevelled (Dsh), each pathway has specific and distinct effectors. One explanation for the pathway specificity is that signal-induced conformational changes result in unique Fz-Dsh interactions. Our mutational analyses of Fz-Dsh activities in vivo do however not support this model, since both pathways are affected by all mutations tested. Alternatively, the interaction of Fz or Dsh with other proteins could modulate the signaling outcome. We examined the role of a Dsh-binding PCP molecule, Diego (Dgo), in both Wnt-Fz/beta-catenin and Fz/PCP signaling. Both loss-of-function and gain-of-function results suggest that Dgo promotes Fz-Dsh/PCP signaling at the expense of Wnt-Fz/beta-catenin signaling. Our data suggest that Dgo sequesters Dsh to a functionally distinct Fz/PCP signaling compartment within the cell.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Transporte/fisiologia , Proteínas de Drosophila/fisiologia , Receptores Frizzled/metabolismo , Fosfoproteínas/metabolismo , Transdução de Sinais/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/química , Sequência de Aminoácidos , Animais , Linhagem Celular , Citoplasma/metabolismo , Proteínas Desgrenhadas , Drosophila , Receptores Frizzled/química , Humanos , Imuno-Histoquímica , Dados de Sequência Molecular , Fosfoproteínas/química , Homologia de Sequência de Aminoácidos
6.
Development ; 133(17): 3283-93, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16887833

RESUMO

Ommatidial rotation is a cell motility read-out of planar cell polarity (PCP) signaling in the Drosophila eye. Although the signaling aspects of PCP establishment are beginning to be unraveled, the mechanistic aspects of the associated ommatidial rotation process remain unknown. Here, we demonstrate that the Drosophila DE- and DN-cadherins have opposing effects on rotation. DE-cadherin promotes rotation, as DE-cad mutant ommatidia rotate less than wild type or not at all. By contrast, the two DN-cadherins act to restrict this movement, with ommatidia rotating too fast in the mutants. The opposing effects of DE- and DN-cadherins result in a coordinated cellular movement, enabling ommatidia of the same stage to rotate simultaneously. Genetic interactions, phenotypic analysis and localization studies indicate that EGF-receptor and Frizzled-PCP signaling feed into the regulation of cadherin activity and localization in this context. Thus, DE- and DN-cadherins integrate inputs from at least two signaling pathways, resulting in a coordinated cell movement. A similar input into mammalian E- and N-cadherins might function in the progression of diseases such as metastatic ovarian cancer.


Assuntos
Caderinas/fisiologia , Movimento Celular/fisiologia , Drosophila/crescimento & desenvolvimento , Olho/crescimento & desenvolvimento , Alelos , Animais , Animais Geneticamente Modificados , Caderinas/genética , Olho/citologia , Receptores Frizzled/fisiologia , Fenótipo , Transdução de Sinais
7.
Mech Dev ; 119(1): 9-20, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12385750

RESUMO

Nemo-like kinases define a novel family of serine/threonine kinases that are involved in integrating multiple signaling pathways. They are conserved regulators of Wnt/Wingless pathways, which may coordinate Wnt with TGFbeta-mediated signaling. Drosophila nemo was identified through its involvement in epithelial planar polarity, a process regulated by a non-canonical Wnt pathway. We have previously found that ectopic expression of Nemo using the Gal4-UAS system resulted in embryonic lethality associated with defects in patterning and head development. In this study we present our analyses of the phenotypes of germline clone-derived embryos. We observe lethality associated with head defects and reduction of programmed cell death and conclude that nmo is an essential gene. We also present data showing that nmo is involved in regulating apoptosis during eye development, based on both loss of function phenotypes and on genetic interactions with the pro-apoptotic gene reaper. Finally, we present genetic data from the adult wing that suggest the activity of ectopically expressed Nemo can be modulated by Jun N-terminal kinase (JNK) signaling. Such an observation supports the model that there is cross-talk between Wnt, TGFbeta and JNK signaling at multiple stages of development.


Assuntos
Proteínas de Drosophila , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Quinases JNK Ativadas por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Animais , Apoptose , Morte Celular , Cruzamentos Genéticos , Drosophila melanogaster , Epiderme/embriologia , Epiderme/metabolismo , Heterozigoto , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , MAP Quinase Quinase 4 , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fenótipo , Células Fotorreceptoras de Invertebrados/embriologia , Transdução de Sinais , Fatores de Tempo , Fator de Crescimento Transformador beta/metabolismo , Transgenes
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