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1.
Sci Rep ; 10(1): 20562, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33239665

RESUMO

Utilizing plant biomass for bioethanol production requires an understanding of the molecular mechanisms involved in plant cell wall assembly. Arabinogalactan-proteins (AGPs) are glycoproteins that interact with other cell wall polymers to influence plant growth and developmental processes. Glucuronic acid, which is transferred to the AGP glycan by ß-glucuronosyltransferases (GLCATs), is the only acidic sugar in AGPs with the ability to bind calcium. We carried out a comprehensive genome-wide analysis of a putative GLCAT gene family involved in AGP biosynthesis by examining its sequence diversity, genetic architecture, phylogenetic and motif characteristics, selection pressure and gene expression in plants. We report the identification of 161 putative GLCAT genes distributed across 14 plant genomes and a widely conserved GLCAT catalytic domain. We discovered a phylogenetic clade shared between bryophytes and higher land plants of monocot grass and dicot lineages and identified positively selected sites that do not result in functional divergence of GLCATs. RNA-seq and microarray data analyses of the putative GLCAT genes revealed gene expression signatures that likely influence the assembly of plant cell wall polymers which is critical to the overall growth and development of edible and bioenergy crops.


Assuntos
Galactanos/biossíntese , Glucuronosiltransferase/genética , Mucoproteínas/biossíntese , Sequência de Aminoácidos , Parede Celular/metabolismo , Galactanos/genética , Genoma de Planta , Ácido Glucurônico/química , Ácido Glucurônico/metabolismo , Glucuronosiltransferase/metabolismo , Glicoproteínas/metabolismo , Mucoproteínas/genética , Filogenia , Desenvolvimento Vegetal , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Plantas/genética , Plantas/metabolismo , Análise de Sequência de DNA/métodos
2.
Mol Biol Rep ; 47(10): 7815-7829, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33011893

RESUMO

Fasciclin-like arabinogalactan proteins (FLAs), a class of arabinogalactan proteins (AGPs) are involved in plant growth and development via cell communication and adhesion. FLAs were also associated with fiber and wood formation in plants but no information is available about the roles of FLA proteins during fibre development of jute. Here, we performed molecular characterization, evolutionary relationship and expression profiling of FLAs proteins in jute (Corchorus olitorius). In total, nineteen CoFLA genes have been identified in jute genome, which were divided into four classes like FLAs of other species based on protein structure and similarity. All CoFLAs have N-terminal signal peptide and one or two FAS domain while two FLAs lack well defined AGP region and eight FLAs were devoid of C-terminal glycosylphosphatidylinositol (GPI) anchor. Expression analysis of different regions of jute stem suggested their involvement in different fiber development stages. Four genes CoFLA 11, 12, 20, and 23 were highly or predominately expressed in fiber containing bark tissues while the expression levels of six CoFLA genes 02, 03, 04, 06, 14 and 19 were comparatively higher in stick. Higher transcripts levels of CoFLA 12 and 20 in the middle bark tissues suggest their involvement in fiber elongation. In contrast, the CoFLA 11 and 23 were more expressed in bottom bark tissues suggesting their potential involvement in secondary cell wall synthesis. Our study can serve as solid foundation for further functional exploration of FLAs and in future breeding program of jute aiming fiber improvement.


Assuntos
Corchorus , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Mucoproteínas , Casca de Planta , Corchorus/genética , Corchorus/metabolismo , Estudo de Associação Genômica Ampla , Mucoproteínas/biossíntese , Mucoproteínas/genética , Casca de Planta/genética , Casca de Planta/metabolismo , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética
3.
J Clin Exp Hematop ; 59(4): 187-195, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31866620

RESUMO

The antigenic heterogeneity of the reticular framework of the white pulp and marginal zone is well documented in the human adult spleen. Immunostaining of α-smooth muscle actin characterizes the heterogeneity of the reticular framework of the white pulp and marginal zone. In the human spleen, the blood cells flow in an open circulation. T and B lymphocytes flow out from the arterial terminal, and migrate in the reticular framework. Homing of lymphocytes to lymphoid tissues is regulated by selective interactions between cell surface homing receptors and tissue vascular addressins at sites of lymphocyte recruitment from the blood. In the present study, mucosal addressin cell adhesion molecule-1 was selectively expressed on α-smooth muscle actin-positive reticular framework. The reticular framework may function in lymphocyte homing and segregation into the periarteriolar lymphoid sheath, lymph follicle and marginal zone.


Assuntos
Actinas/biossíntese , Linfócitos B/metabolismo , Moléculas de Adesão Celular/biossíntese , Regulação da Expressão Gênica , Mucoproteínas/biossíntese , Baço/metabolismo , Linfócitos T/metabolismo , Linfócitos B/ultraestrutura , Humanos , Baço/ultraestrutura , Linfócitos T/ultraestrutura
4.
Plant Reprod ; 31(1): 67-75, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29470639

RESUMO

The arabinogalactan protein (AGP) family is one of the most complex protein families and is ubiquitous in the plant kingdom. Moreover, it has been demonstrated to play various roles during plant reproduction. A typical AGP contains a hydroxyproline-rich core protein with high heterogeneity and varying numbers of polysaccharide side chains. However, the functions of the polysaccharide components (i.e. AG sugar chains) remain largely unknown due to the general difficulties associated with studying sugar chains in glycobiology. In recent years, methodological breakthroughs have resulted in substantial progress in AGP research. Here, we summarise the multiple roles of AGPs during plant gametophyte development and male-female communication, with a focus on recent advances. In addition, we discuss the analytical tools used in AGP research, and the biosynthesis and function of AG sugar chains. A comprehensive understanding of the AGP family will help clarify the mechanisms precisely controlling reproductive processes.


Assuntos
Mucoproteínas/fisiologia , Fenômenos Fisiológicos Vegetais , Açúcares/química , Pesquisa Biomédica , Mucoproteínas/biossíntese , Mucoproteínas/química , Proteínas de Plantas/biossíntese , Proteínas de Plantas/química , Proteínas de Plantas/fisiologia , Reprodução , Açúcares/metabolismo
5.
PLoS One ; 12(2): e0172682, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28234963

RESUMO

The study was focused on assessing the presence of arabinogalactan proteins (AGPs) and pectins within the cell walls as well as prenyl lipids, sodium and chlorine content in leaves of Tilia x euchlora trees. The leaves that were analyzed were collected from trees with and without signs of damage that were all growing in the same salt stress conditions. The reason for undertaking these investigations was the observations over many years that indicated that there are trees that present a healthy appearance and trees that have visible symptoms of decay in the same habitat. Leaf samples were collected from trees growing in the median strip between roadways that have been intensively salted during the winter season for many years. The sodium content was determined using atomic spectrophotometry, chloride using potentiometric titration and poly-isoprenoids using HPLC/UV. AGPs and pectins were determined using immunohistochemistry methods. The immunohistochemical analysis showed that rhamnogalacturonans I (RG-I) and homogalacturonans were differentially distributed in leaves from healthy trees in contrast to leaves from injured trees. In the case of AGPs, the most visible difference was the presence of the JIM16 epitope. Chemical analyses of sodium and chloride showed that in the leaves from injured trees, the level of these ions was higher than in the leaves from healthy trees. Based on chromatographic analysis, four poly-isoprenoid alcohols were identified in the leaves of T. x euchlora. The levels of these lipids were higher in the leaves from healthy trees. The results suggest that the differences that were detected in the apoplast and symplasm may be part of the defensive strategy of T. x euchlora trees to salt stress, which rely on changes in the chemical composition of the cell wall with respect to the pectic and AGP epitopes and an increased synthesis of prenyl lipids.


Assuntos
Adaptação Fisiológica , Parede Celular/efeitos dos fármacos , Lipídeos/biossíntese , Cloreto de Sódio/farmacologia , Estresse Fisiológico , Terpenos/metabolismo , Tilia/efeitos dos fármacos , Álcoois/isolamento & purificação , Álcoois/metabolismo , Parede Celular/química , Parede Celular/metabolismo , Lipídeos/isolamento & purificação , Mucoproteínas/biossíntese , Mucoproteínas/isolamento & purificação , Pectinas/biossíntese , Pectinas/isolamento & purificação , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Proteínas de Plantas/biossíntese , Proteínas de Plantas/isolamento & purificação , Salinidade , Solo/química , Terpenos/isolamento & purificação , Tilia/metabolismo , Árvores/efeitos dos fármacos , Árvores/metabolismo
6.
Oncogene ; 36(22): 3094-3103, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27941872

RESUMO

The mechanisms of initiation of pancreatic ductal adenocarcinoma (PDAC) are still largely unknown. In the present study, we analysed the role of anterior gradient-2 (AGR2) in the earliest stages of pancreatic neoplasia. Immunohistochemical analysis of chronic pancreatitis (CP) and peritumoral areas in PDAC tissues showed that AGR2 was present in tubular complexes (TC) and early pancreatic intraepithelial neoplasia (PanINs). Moreover, AGR2 was also found in discrete subpopulations of non-transformed cells neighbouring these pre-neoplastic lesions. In primary cells derived from human patient-derived xenograft (PDX) model, flow-cytometry revealed that AGR2 was overexpressed in pancreatic cancer stem cells (CSC) compared with non-stem cancer cells. In LSL-KrasG12D;Pdx1-Cre (KC) mouse model Agr2 induction preceded the formation of pre-neoplastic lesions and their development was largely inhibited by Agr2 deletion in engineered LSL-KrasG12D;Pdx1-Cre; Agr2-/- mice. In vitro, AGR2 expression was stimulated by tunicamycin-induced endoplasmic reticulum (ER) stress in both KRAS wild-type normal pancreas cells, as well as in KRAS mutated pancreatic cancer cells and was essential for ER homoeostasis. The unfolded protein response proteins GRP78, ATF6 and XBP1s were found expressed in CP and PDAC peritumoral tissues, but in contrast to AGR2, their expression was switched off during TC and PanIN formation. Real-time PCR and ELISA analyses showed that ER stress induced a pro-inflammatory phenotype in pancreatic normal, cancer and stellate cells. Moreover, AGR2 expression was inducible by paracrine transfer of ER stress and pro-inflammation between different pancreatic cell types. Our findings demonstrate that AGR2 induced in ER-stressed and inflammatory pre-neoplastic pancreas is a potential marker of cancer progenitor cells with an important functional role in PDAC initiation.


Assuntos
Carcinoma Ductal Pancreático/patologia , Estresse do Retículo Endoplasmático/fisiologia , Mucoproteínas/metabolismo , Neoplasias Pancreáticas/patologia , Animais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Modelos Animais de Doenças , Chaperona BiP do Retículo Endoplasmático , Humanos , Camundongos , Mucoproteínas/biossíntese , Mucoproteínas/deficiência , Mucoproteínas/genética , Proteínas Oncogênicas , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo
7.
Pathology ; 47(1): 38-44, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25474513

RESUMO

Nodular gastritis is a form of chronic Helicobacter pylori gastritis affecting the gastric antrum and characterised endoscopically by the presence of small nodular lesions resembling gooseflesh. It is generally accepted that hyperplasia of lymphoid follicles histologically characterises nodular gastritis; however, quantitative analysis in support of this hypothesis has not been reported. Our goal was to determine whether nodular gastritis is characterised by lymphoid follicle hyperplasia.The number, size, and location of lymphoid follicles in nodular gastritis were determined and those properties compared to samples of atrophic gastritis. The percentages of high endothelial venule (HEV)-like vessels were also evaluated.The number of lymphoid follicles was comparable between nodular and atrophic gastritis; however, follicle size in nodular gastritis was significantly greater than that seen in atrophic gastritis. Moreover, lymphoid follicles in nodular gastritis were positioned more superficially than were those in atrophic gastritis. The percentage of MECA-79 HEV-like vessels was greater in areas with gooseflesh-like lesions in nodular versus atrophic gastritis.Superficially located hyperplastic lymphoid follicles characterise nodular gastritis, and these follicles correspond to gooseflesh-like nodular lesions observed endoscopically. These observations suggest that MECA-79 HEV-like vessels could play at least a partial role in the pathogenesis of nodular gastritis.


Assuntos
Mucosa Gástrica/patologia , Gastrite/patologia , Tecido Linfoide/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Superfície/análise , Antígenos de Superfície/biossíntese , Moléculas de Adesão Celular , Criança , Pré-Escolar , Endotélio Vascular/metabolismo , Feminino , Gastrite/microbiologia , Infecções por Helicobacter/complicações , Helicobacter pylori , Humanos , Imunoglobulinas/análise , Imunoglobulinas/biossíntese , Imuno-Histoquímica , Tecido Linfoide/irrigação sanguínea , Tecido Linfoide/metabolismo , Masculino , Proteínas de Membrana/análise , Proteínas de Membrana/biossíntese , Pessoa de Meia-Idade , Mucoproteínas/análise , Mucoproteínas/biossíntese , Adulto Jovem
8.
Cancer Res ; 75(2): 356-66, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25488752

RESUMO

Agr2 is a disulfide isomerase residing in the endoplasmic reticulum (ER), which physiologically regulates protein folding and mediates resistance to ER stress. Agr2 is overexpressed in adenocarcinomas of various organs, where it participates in neoplastic transformation and metastasis, therefore acts as a pro-oncogenic protein. Besides its normal localization in the ER, Agr2 is also found in the serum and urine of cancer patients, although the physiological significance of extracellular Agr2 is poorly understood. In this study, we demonstrated that extracellular Agr2 can activate stromal fibroblasts and promote fibroblast-associated cancer invasion in gastric signet-ring cell carcinoma (SRCC), where Agr2 is highly expressed. Agr2 secreted from SRCC cells was incorporated by the surrounding gastric fibroblasts and promoted invasion by these cells. In turn, activated fibroblasts coordinated the invasive behavior of fibroblasts and cancer cells. Our findings suggested that Agr2 drives progression of gastric SRCC by exerting paracrine effects on fibroblasts in the tumor microenvironment, acting also to increase the growth and resistance of SRCC cells to oxidative and hypoxic stress as cell autonomous effects.


Assuntos
Carcinoma de Células em Anel de Sinete/metabolismo , Carcinoma de Células em Anel de Sinete/patologia , Mucoproteínas/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Animais , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Fibroblastos/metabolismo , Fibroblastos/patologia , Células HEK293 , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Mucoproteínas/biossíntese , Invasividade Neoplásica , Proteínas Oncogênicas , Estresse Oxidativo/fisiologia , Células Estromais/metabolismo , Células Estromais/patologia
9.
Andrology ; 2(2): 282-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24519996

RESUMO

Seminoma, the most common testicular malignant neoplasm, originates from germ cells and is characterized by the presence of numerous tumour-infiltrating lymphocytes (TILs). Although it is widely accepted that TILs function in surveillance and cytotoxicity in various tumours including seminoma, detailed mechanisms governing TIL recruitment are not fully understood. It has been shown that high endothelial venule (HEV)-like vessels are induced in inflamed and neoplastic tissues and contribute to lymphocyte recruitment in a manner similar to the way physiological lymphocyte homing occurs in secondary lymphoid organs. Here, we report that HEV-like vessels, which express MECA-79(+) 6-sulfo sialyl Lewis X-capped structures, are induced in TIL aggregates in seminoma, and that such vessels potentially recruit circulating lymphocytes, as an E-selectin•IgM chimera bound these vessels in a calcium-dependent manner. These HEV-like vessels express intercellular adhesion molecule 1 (ICAM-1), but not vascular cell adhesion molecule 1 (VCAM-1) or mucosal addressin cell adhesion molecule 1 (MAdCAM-1), which likely contributes to lymphocyte firm attachment. We also found that the number of T cells attached to the luminal surface of HEV-like vessels was greater than the number of B cells (p < 0.0001). Interestingly, while CD8(+) cytotoxic T lymphocytes (CTLs) attached to the lumen of HEV-like vessels were scarcely detected, significant numbers of proliferative CTLs were observed outside vessels. These histological findings strongly suggest that TILs, particularly T cells, are recruited to seminoma tissues via HEV-like vessels, and that tumour-infiltrating CTLs then undergo proliferation after transmigration through HEV-like vessels in testicular seminoma.


Assuntos
Linfócitos do Interstício Tumoral/imunologia , Seminoma/patologia , Linfócitos T Citotóxicos/imunologia , Neoplasias Testiculares/patologia , Testículo/patologia , Adulto , Antígenos CD20/biossíntese , Antígenos de Superfície/biossíntese , Linfócitos B/imunologia , Complexo CD3/biossíntese , Antígenos CD79/biossíntese , Moléculas de Adesão Celular , Proliferação de Células , Endotélio Vascular , Humanos , Imunoglobulinas/biossíntese , Molécula 1 de Adesão Intercelular/biossíntese , Antígenos CD15/análogos & derivados , Ativação Linfocitária , Contagem de Linfócitos , Masculino , Proteínas de Membrana/biossíntese , Pessoa de Meia-Idade , Mucoproteínas/biossíntese , Oligossacarídeos/biossíntese , Seminoma/irrigação sanguínea , Antígeno Sialil Lewis X/análogos & derivados , Testículo/irrigação sanguínea , Testículo/imunologia , Molécula 1 de Adesão de Célula Vascular/biossíntese , Vênulas/metabolismo
10.
J Biol Chem ; 288(6): 4321-33, 2013 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-23209296

RESUMO

Recent studies of epithelial tissues have revealed the presence of tissue-specific stem cells that are able to establish multiple cell lineages within an organ. The stem cells give rise to progenitors that replicate before differentiating into specific cell lineages. The mechanism by which homeostasis is established between proliferating stem or progenitor cells and terminally differentiated cells is unclear. This study demonstrates that Agr2 expression by mucous neck cells in the stomach promotes the differentiation of multiple cell lineages while also inhibiting the proliferation of stem or progenitor cells. When Agr2 expression is absent, gastric mucous neck cells increased in number as does the number of proliferating cells. Agr2 expression loss also resulted in the decline of terminally differentiated cells, which was supplanted by cells that exhibited nuclear SOX9 labeling. Sox9 expression has been associated with progenitor and stem cells. Similar effects of the Agr2 null on cell proliferation in the intestine were also observed. Agr2 consequently serves to maintain the balance between proliferating and differentiated epithelial cells.


Assuntos
Diferenciação Celular , Linhagem da Célula , Regulação da Expressão Gênica no Desenvolvimento , Mucoproteínas/biossíntese , Células-Tronco/metabolismo , Estômago/embriologia , Animais , Proliferação de Células , Hiperplasia , Camundongos , Camundongos Mutantes , Mucoproteínas/genética , Proteínas Oncogênicas , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Células-Tronco/patologia , Estômago/patologia
11.
Mol Reprod Dev ; 79(8): 517-24, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22674895

RESUMO

Sperm proteins of marine sessile invertebrates have been extensively studied to understand the molecular basis of reproductive isolation. Apart from molecules such as bindin of sea urchins or lysin of abalone species, the acrosomal protein M7 lysin of Mytilus edulis has been analyzed. M7 lysin was found to be under positive selection, but mechanisms driving the evolution of this protein are not fully understood. To explore functional aspects, this study investigated the protein expression pattern of M7 and M6 lysin in gametes and somatic tissue of male and female M. edulis. The study employs a previously published monoclonal antibody (G26-AG8) to investigate M6 and M7 lysin protein expression, and explores expression of both genes. It is shown that these proteins and their encoding genes are expressed in gametes and somatic tissue of both sexes. This is in contrast to sea urchin bindin and abalone lysin, in which gene expression is strictly limited to males. Although future studies need to clarify the functional importance of both acrosomal proteins in male and female somatic tissue, new insights into the evolution of sperm proteins in marine sessile invertebrates are possible. This is because proteins with male-specific expression (bindin, lysin) might evolve differently than proteins with expression in both sexes (M6/M7 lysin), and the putative function of both proteins in females opens the possibility that the evolution of M6/M7 lysin is under sexual antagonistic selection, for example, mutations beneficial to the acrosomal function that are less beneficial the function in somatic tissue of females.


Assuntos
Acrossomo/metabolismo , Evolução Molecular , Regulação da Expressão Gênica/fisiologia , Mucoproteínas/biossíntese , Mytilus edulis/metabolismo , Oócitos/metabolismo , Animais , Embrião não Mamífero/citologia , Embrião não Mamífero/embriologia , Feminino , Masculino , Mytilus edulis/citologia , Mytilus edulis/embriologia , Oócitos/citologia
12.
Am J Respir Cell Mol Biol ; 47(2): 178-85, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22403803

RESUMO

Mucins are gel-forming proteins that are responsible for the characteristic viscoelastic properties of mucus. Mucin overproduction is a hallmark of asthma, but the cellular requirements for airway mucin production are poorly understood. The endoplasmic reticulum (ER) protein anterior gradient homolog 2 (AGR2) is required for production of the intestinal mucin MUC2, but its role in the production of the airway mucins MUC5AC and MUC5B is not established. Microarray data were analyzed to examine the relationship between AGR2 and MUC5AC expression in asthma. Immunofluorescence was used to localize AGR2 in airway cells. Coimmunoprecipitation was used to identify AGR2-immature MUC5AC complexes. Agr2(-/-) mice were used to determine the role of AGR2 in allergic airway disease. AGR2 localized to the ER of MUC5AC- and MUC5B-producing airway cells and formed a complex with immature MUC5AC. AGR2 expression increased together with MUC5AC expression in airway epithelium from "Th2-high" asthmatics. Allergen-challenged Agr2(-/-) mice had greater than 50% reductions in MUC5AC and MUC5B proteins compared with allergen-challenged wild-type mice. Impaired mucin production in Agr2(-/-) mice was accompanied by an increase in the proportion of mucins contained within the ER and by evidence of ER stress in airway epithelium. This study shows that AGR2 increases with mucin overproduction in individuals with asthma and in mouse models of allergic airway disease. AGR2 interacts with immature mucin in the ER and loss of AGR2 impairs allergen-induced MUC5AC and MUC5B overproduction.


Assuntos
Alérgenos/administração & dosagem , Asma/metabolismo , Mucina-5AC/biossíntese , Mucina-5B/biossíntese , Mucoproteínas/biossíntese , Proteínas/metabolismo , Alérgenos/imunologia , Animais , Asma/genética , Asma/imunologia , Hiper-Reatividade Brônquica/genética , Hiper-Reatividade Brônquica/imunologia , Hiper-Reatividade Brônquica/metabolismo , Linhagem Celular Tumoral , Retículo Endoplasmático/imunologia , Retículo Endoplasmático/metabolismo , Expressão Gênica , Humanos , Hipersensibilidade Imediata/genética , Hipersensibilidade Imediata/imunologia , Hipersensibilidade Imediata/metabolismo , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Camundongos , Camundongos Transgênicos , Mucina-5AC/genética , Mucina-5AC/imunologia , Mucina-5AC/metabolismo , Mucina-5B/genética , Mucina-5B/imunologia , Mucina-5B/metabolismo , Mucoproteínas/genética , Mucoproteínas/imunologia , Mucoproteínas/metabolismo , Proteínas Oncogênicas , Proteínas/genética , Proteínas/imunologia , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo , Células Th2/imunologia , Células Th2/metabolismo
13.
Biochim Biophys Acta ; 1824(5): 711-22, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22425601

RESUMO

Fiber-forming proteins and peptides are being scrutinized as a promising source of building blocks for new nanomaterials. Arabinogalactan-like (AGL) proteins expressed at the symbiotic interface between plant roots and arbuscular mycorrhizal fungi have novel sequences, hypothesized to form polyproline II (PPII) helix structures. The functional nature of these proteins is unknown but they may form structures for the establishment and maintenance of fungal hyphae. Here we show that recombinant AGL1 (rAGL1) and recombinant AGL3 (rAGL3) are extended proteins based upon secondary structural characteristics determined by electronic circular dichroism (CD) spectroscopy and can self-assemble into fibers and microtubes as observed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). CD spectroscopy results of synthetic peptides based on repeat regions in AGL1, AGL2 and AGL3 suggest that the synthetic peptides contain significant amounts of extended PPII helices and that these structures are influenced by ionic strength and, at least in one case, by concentration. Point mutations of a single residue of the repeat region of AGL3 resulted in altered secondary structures. Self-assembly of these repeats was observed by means of AFM and optical microscopy. Peptide (APADGK)(6) forms structures with similar morphology to rAGL1 suggesting that these repeats are crucial for the morphology of rAGL1 fibers. These novel self-assembling sequences may find applications as precursors for bioinspired nanomaterials.


Assuntos
Materiais Biomiméticos/síntese química , Mucoproteínas/química , Micorrizas/química , Nanofibras/química , Peptídeos/síntese química , Polilisina/química , Dicroísmo Circular , Escherichia coli/genética , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Mucoproteínas/biossíntese , Mucoproteínas/genética , Micorrizas/fisiologia , Nanofibras/ultraestrutura , Concentração Osmolar , Peptídeos/química , Proteínas de Plantas/biossíntese , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas/microbiologia , Mutação Puntual , Estrutura Secundária de Proteína , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Simbiose
14.
Plant Biol (Stuttg) ; 13(3): 431-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21489093

RESUMO

AtAGP17 and AtAGP19 are members of the lysine-rich arabinogalactan protein (AGP) subfamily in Arabidopsis. Detailed anatomical analysis of promoter activity of the AtAGP19 gene was carried out using transgenic Arabidopsis plants expressing a P(AtAGP19):GUS fusion. AtAGP19 promoter activity was tissue-specific and associated with vascular bundles, particularly differentiating xylem elements. Peptide-specific antibodies were raised against the Lys-rich regions of AtAGP17 and AtAGP19 and used to study the organ-specific expression patterns of these two AGPs. AtAGP17 and AtAGP19 were most abundant in roots and flowers, moderately abundant in stems, seedlings and siliques and virtually absent in leaves. Antibodies specific for AtAGP17 and AtAGP19, as reported here, represent valuable tools for understanding the biology of these two AGPs.


Assuntos
Proteínas de Arabidopsis/biossíntese , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Mucoproteínas/biossíntese , Mucoproteínas/genética , Sequência de Aminoácidos , Anticorpos/química , Anticorpos/imunologia , Especificidade de Anticorpos , Proteínas de Arabidopsis/imunologia , Western Blotting , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Lisina/metabolismo , Dados de Sequência Molecular , Mucoproteínas/imunologia , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Proteínas de Plantas/imunologia , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas
15.
Methods Mol Biol ; 715: 209-19, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21222087

RESUMO

Structural proteins of the primary cell wall present unusual but interesting problems for structural biologists in particular and plant biologists in general. As structure is the key to function; then the biochemical isolation of these glycoproteins for further study is paramount. Here, we detail the "classical" method for isolating soluble extensin monomers by elution of monomeric precursors to network extensin from tissue cultures. We also outline an additional approach involving genetic engineering that can potentially yield the complete genomic range of extensins and other hydroxyproline-rich glycoprotein (HRGPs) currently underutilized for biotechnology.


Assuntos
Parede Celular/química , Glicoproteínas/química , Mucoproteínas/isolamento & purificação , Nicotiana/química , Técnicas de Cultura de Células , Glicoproteínas/biossíntese , Glicoproteínas/genética , Glicoproteínas/isolamento & purificação , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/isolamento & purificação , Mucoproteínas/biossíntese , Proteínas Periplásmicas/biossíntese , Proteínas Periplásmicas/isolamento & purificação , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Nicotiana/genética , Nicotiana/metabolismo , Transformação Genética
16.
Biochem Biophys Res Commun ; 404(1): 261-7, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21111712

RESUMO

Th2 cytokines and their downstream Janus kinase (JAK)-signal transducer and activation of transcription (STAT) pathways play a critical role in allergic asthma. We studied the effects of a pan-JAK inhibitor, pyridone 6 (P6), on asthmatic responses in a mouse model and investigated the mechanism for its biological effects. Mice were sensitized and challenged by ovalbumin (OVA). P6 treatment during the challenge phase suppressed eosinophilia in bronchoalveolar lavage (BAL) fluids but did not affect airway hyperresponsiveness (AHR). To improve the efficacy of the JAK inhibitor, P6 was encapsulated in polylactic-coglycolic acid nanoparticles (P6-PLGA). P6-PLGA treatment just before OVA challenge suppressed both airway eosinophilia and AHR. Although the IL-13 levels in BAL fluids and the OVA-specific IgE levels in serum after the challenge phase treatment with P6-PLGA were similar to those after a sham treatment, the eotaxin levels in BAL fluids and lung mCLCA3/Gob-5 expression were decreased in P6-PLGA-treated mice. Interestingly, the local IL-13 levels and serum OVA-specific IgE were decreased, while IL-17-producing T cells were increased by P6-PLGA treatment during the sensitization plus challenge phases. In vitro, P6 strongly suppressed the differentiation of Th2 from naive CD4 T cells, but it partly enhanced Th17 differentiation. P6 potently suppressed IL-13-mediated STAT6 activation and mCLCA3/Gob-5 expression in mouse tracheal epithelial cells. These findings suggest that the JAK inhibitor P6 suppresses asthmatic responses by inhibiting Th2 inflammation and that application of PLGA nanoparticles improves the therapeutic potency of P6.


Assuntos
Asma/tratamento farmacológico , Benzimidazóis/uso terapêutico , Hiper-Reatividade Brônquica/tratamento farmacológico , Janus Quinases/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico , Piridonas/uso terapêutico , Animais , Asma/imunologia , Asma/fisiopatologia , Benzimidazóis/administração & dosagem , Hiper-Reatividade Brônquica/imunologia , Hiper-Reatividade Brônquica/fisiopatologia , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Cápsulas , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/biossíntese , Eosinofilia/tratamento farmacológico , Eosinofilia/imunologia , Interleucina-13/imunologia , Ácido Láctico/química , Pulmão/imunologia , Camundongos , Mucoproteínas/antagonistas & inibidores , Mucoproteínas/biossíntese , Nanopartículas/administração & dosagem , Nanopartículas/química , Nanopartículas/uso terapêutico , Ovalbumina/imunologia , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Piridonas/administração & dosagem , Fator de Transcrição STAT6/metabolismo , Células Th2/imunologia
17.
Plant J ; 61(6): 1107-21, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20409281

RESUMO

Plant cell walls are composites of various carbohydrates, proteins and other compounds. Cell walls provide plants with strength and protection, and also represent the most abundant source of renewable biomass. Despite the importance of plant cell walls, comparatively little is known about the identities of genes and functions of proteins involved in their biosynthesis. The model plant Arabidopsis and the availability of its genome sequence have been invaluable for the identification and functional characterization of genes encoding enzymes involved in plant cell-wall biosynthesis. This review covers recent progress in the identification and characterization of genes encoding proteins involved in the biosynthesis of Arabidopsis cell-wall polysaccharides and arabinogalactan proteins. These studies have improved our understanding of both the mechanisms of cell-wall biosynthesis and the functions of various cell-wall polymers, and have highlighted areas where further research is needed.


Assuntos
Arabidopsis/genética , Parede Celular/enzimologia , Mucoproteínas/biossíntese , Polissacarídeos/biossíntese , Arabidopsis/enzimologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Parede Celular/genética , Celulose/biossíntese , Genes de Plantas , Glucanos/biossíntese , Mananas/biossíntese , Pectinas/biossíntese , Proteínas de Plantas/biossíntese , Xilanos/biossíntese
18.
Pediatr Transplant ; 14(5): 614-7, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20214743

RESUMO

We studied the effect of the combined treatment with FK506, FTY720, and ex vivo graft irradiation. Five groups of SBT animals were studied on days 3, 5, and 7 after operation (untreated, FK506, FTY720, FK506 + FTY720, FK506 + FTY720 + irradiation). Indirect immunoperoxidase staining was performed against CD4 and MAdCAM-1. The numbers of CD4 positive cells in allografts were also analyzed by flow cytometry. The graft survival was prolonged in all of the FK506- and FTY720-treated groups. SBT allografts treated by FK506 and FTY720 demonstrated less infiltration of CD4 positive cells, but the irradiation group did not show any effects on its expression. In FK506- and FTY720-treated groups, MAdCAM-1 expression on the HEVs in PPs was up-regulated, and its expression on the ECVs in the LP was down-regulated compared with other allograft groups. Irradiation did not show any effects on MAdCAM-1 expression on both HEVs in PPs and ECVs in LP. FK506 and FTY720 prevented the infiltration of CD4 positive cells, the down-regulation of MAdCAM-1 expression on HEVs in PPs, and the up-regulation of MAdCAM-1 expression on ECVs in LP during the early phase of SBT.


Assuntos
Imunoglobulinas/biossíntese , Imunossupressores/farmacologia , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/efeitos da radiação , Mucoproteínas/biossíntese , Propilenoglicóis/farmacologia , Esfingosina/análogos & derivados , Tacrolimo/farmacologia , Animais , Terapia Combinada , Cloridrato de Fingolimode , Intestino Delgado/metabolismo , Intestino Delgado/transplante , Ratos , Esfingosina/farmacologia , Transplantes
19.
J Histochem Cytochem ; 58(5): 413-20, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20086233

RESUMO

Tissue microarray (TMA) is a new high-throughput method that enables simultaneous analysis of the profiles of protein expression in multiple tissue samples. TMA technology has not previously been adapted for physiological and pathophysiological studies of rodent kidneys. We have evaluated the validity and reliability of using TMA to assess protein expression in mouse and rat kidneys. A representative TMA block that we have produced included: (1) mouse and rat kidney cortex, outer medulla, and inner medulla fixed with different fixatives; (2) rat kidneys at different stages of development fixed with different fixatives; (3) mouse and rat kidneys with different physiological or pathophysiological treatments; and (4) built-in controls. As examples of the utility, immunostaining for cyclooxygenase-2, renin, Tamm Horsfall protein, aquaporin-2, connective tissue growth factor, and synaptopodin was carried out with kidney TMA slides. Quantitative analysis of cyclooxygense-2 expression in kidneys confirms that individual cores provide meaningful representations comparable to whole-kidney sections. These studies show that kidney TMA technique is a promising and useful tool for investigating the expression profiles of proteins of interest in rodent kidneys under different physiological and pathophysiological conditions.


Assuntos
Rim/metabolismo , Análise Serial de Tecidos , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Animais , Aquaporina 2/biossíntese , Fator de Crescimento do Tecido Conjuntivo/biossíntese , Ciclo-Oxigenase 2/biossíntese , Fixadores , Imuno-Histoquímica , Rim/anatomia & histologia , Rim/crescimento & desenvolvimento , Camundongos , Mucoproteínas/biossíntese , Ratos , Renina/biossíntese , Fixação de Tecidos , Uromodulina
20.
Hum Pathol ; 40(5): 699-704, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19157500

RESUMO

Mucosal addressin cell adhesion molecule 1, expressed on gut endothelial cells, in conjunction with integrin alpha(4)beta(7), expressed on lymphocytes, is critical in lymphocyte homing to the gut. The mucosal addressin cell adhesion molecule 1/integrin alpha(4)beta(7) pathway is involved in the pathogenesis of chronic intestinal inflammation by recruiting lymphocytes into inflamed gut. We explored the duodenal expression of mucosal addressin cell adhesion molecule 1 and the peripheral T-cell expression of integrin alpha(4)beta(7) in patients with celiac disease. Duodenal biopsies and a peripheral blood sample were collected from 15 celiac patients, before and after 12 months of gluten-free diet, and from 12 control subjects. Treated celiac biopsies were cultured with peptic-tryptic digest of gliadin and/or an anti-interferon alpha neutralizing antibody. Mucosal addressin cell adhesion molecule 1 was determined by confocal immunofluorescence microscopy and immunoblotting. Integrin beta(7)-positive T cells were analyzed by flow cytometry. Mucosal addressin cell adhesion molecule 1 expression was significantly higher in active celiac disease than in normal mucosa. After gluten-free diet, a dramatic reduction of mucosal addressin cell adhesion molecule 1 was also observed. No difference was seen between patients with celiac disease after treatment and controls. Ex vivo peptic-tryptic digest of gliadin challenge induced a marked increase of mucosal addressin cell adhesion molecule 1 expression. Blocking interferon alpha inhibited the peptic-tryptic digest of gliadin-induced mucosal addressin cell adhesion molecule 1 overexpression. The percentage of circulating beta(7)-positive T cells was significantly lower in untreated celiac disease in comparison to controls but normalized after gluten-free diet. Mucosal addressin cell adhesion molecule 1 is strongly up-regulated in active celiac disease dependent on interferon alpha and is associated with peripheral depletion of integrin alpha(4)beta(7)-expressing T cells. We conclude that mucosal addressin cell adhesion molecule 1 may represent an important determinant for the generation of mucosal damage in celiac disease.


Assuntos
Doença Celíaca/imunologia , Duodeno/imunologia , Imunoglobulinas/biossíntese , Mucoproteínas/biossíntese , Subpopulações de Linfócitos T/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Western Blotting , Doença Celíaca/metabolismo , Moléculas de Adesão Celular , Duodeno/metabolismo , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Imunofluorescência , Humanos , Integrinas/imunologia , Integrinas/metabolismo , Microscopia Confocal , Pessoa de Meia-Idade , Técnicas de Cultura de Órgãos
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