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1.
Sensors (Basel) ; 23(4)2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36850785

RESUMEN

In the biometric field, vein identification is a vital process that is constrained by the invisibility of veins as well as other unique features. Moreover, users generally do not wish to have their personal information uploaded to the cloud, so edge computing has become popular for the sake of protecting user privacy. In this paper, we propose a low-complexity and lightweight convolutional neural network (CNN) and we design intellectual property (IP) for shortening the inference time in finger vein recognition. This neural network system can operate independently in client mode. After fetching the user's finger vein image via a near-infrared (NIR) camera mounted on an embedded system, vein features can be efficiently extracted by vein curving algorithms and user identification can be completed quickly. Better image quality and higher recognition accuracy can be obtained by combining several preprocessing techniques and the modified CNN. Experimental data were collected by the finger vein image capture equipment developed in our laboratory based on the specifications of similar products currently on the market. Extensive experiments demonstrated the practicality and robustness of the proposed finger vein identification system.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Humanos , Biometría , Extremidades , Laboratorios
2.
Int J Mol Sci ; 22(20)2021 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-34681875

RESUMEN

Compensatory hepatocyte proliferation and other liver regenerative processes are activated to sustain normal physiological function after liver injury. A major mitogen for liver regeneration is hepatocyte growth factor (HGF), and a previous study indicated that progranulin could modulate c-met, the receptor for HGF, to initiate hepatic outgrowth from hepatoblasts during embryonic development. However, a role for progranulin in compensatory hepatocyte proliferation has not been shown previously. Therefore, this study was undertaken to clarify whether progranulin plays a regulatory role during liver regeneration. To this end, we established a partial hepatectomy regeneration model in adult zebrafish that express a liver-specific fluorescent reporter. Using this model, we found that loss of progranulin A (GrnA) function by intraperitoneal-injection of a Vivo-Morpholino impaired and delayed liver regeneration after partial hepatectomy. Furthermore, transcriptome analysis and confirmatory quantitative real-time PCR suggested that cell cycle progression and cell proliferation was not as active in the morphants as controls, which may have been the result of comparative downregulation of the HGF/c-met axis by 36 h after partial hepatectomy. Finally, liver-specific overexpression of GrnA in transgenic zebrafish caused more abundant cell proliferation after partial hepatectomy compared to wild types. Thus, we conclude that GrnA positively regulates HGF/c-met signaling to promote hepatocyte proliferation during liver regeneration.


Asunto(s)
Hepatectomía/métodos , Factor de Crecimiento de Hepatocito/metabolismo , Hepatocitos/citología , Regeneración Hepática , Progranulinas/metabolismo , Proteínas Proto-Oncogénicas c-met/metabolismo , Proteínas de Pez Cebra/metabolismo , Animales , Proliferación Celular , Factor de Crecimiento de Hepatocito/genética , Hepatocitos/metabolismo , Organogénesis , Progranulinas/genética , Proteínas Proto-Oncogénicas c-met/genética , Transducción de Señal , Pez Cebra , Proteínas de Pez Cebra/genética
3.
J Biol Chem ; 294(7): 2519-2528, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30563844

RESUMEN

Many erythrocyte processes and pathways, including glycolysis, the pentose phosphate pathway (PPP), KCl cotransport, ATP release, Na+/K+-ATPase activity, ankyrin-band 3 interactions, and nitric oxide (NO) release, are regulated by changes in O2 pressure that occur as a red blood cell (RBC) transits between the lungs and tissues. The O2 dependence of glycolysis, PPP, and ankyrin-band 3 interactions (affecting RBC rheology) are controlled by O2-dependent competition between deoxyhemoglobin (deoxyHb), but not oxyhemoglobin (oxyHb), and other proteins for band 3. We undertook the present study to determine whether the O2 dependence of Na+/K+/2Cl- cotransport (catalyzed by Na+/K+/2Cl- cotransporter 1 [NKCC1]) might similarly originate from competition between deoxyHb and a protein involved in NKCC1 regulation for a common binding site on band 3. Using three transgenic mouse strains having mutated deoxyhemoglobin-binding sites on band 3, we found that docking of deoxyhemoglobin at the N terminus of band 3 displaces the protein with no lysine kinase 1 (WNK1) from its overlapping binding site on band 3. This displacement enabled WNK1 to phosphorylate oxidative stress-responsive kinase 1 (OSR1), which, in turn, phosphorylated and activated NKCC1. Under normal solution conditions, the NKCC1 activation increased RBC volume and thereby induced changes in RBC rheology. Because the deoxyhemoglobin-mediated WNK1 displacement from band 3 in this O2 regulation pathway may also occur in the regulation of other O2-regulated ion transporters, we hypothesize that the NKCC1-mediated regulatory mechanism may represent a general pattern of O2 modulation of ion transporters in erythrocytes.


Asunto(s)
Eritrocitos/metabolismo , Hemoglobinas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Miembro 2 de la Familia de Transportadores de Soluto 12/metabolismo , Proteína Quinasa Deficiente en Lisina WNK 1/metabolismo , Animales , Proteína 1 de Intercambio de Anión de Eritrocito/metabolismo , Eritrocitos/citología , Ratones , Fosforilación
4.
Proc Natl Acad Sci U S A ; 113(48): 13732-13737, 2016 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-27856737

RESUMEN

Src homology 2 (SH2) domains are composed of weakly conserved sequences of ∼100 aa that bind phosphotyrosines in signaling proteins and thereby mediate intra- and intermolecular protein-protein interactions. In exploring the mechanism whereby tyrosine phosphorylation of the erythrocyte anion transporter, band 3, triggers membrane destabilization, vesiculation, and fragmentation, we discovered a SH2 signature motif positioned between membrane-spanning helices 4 and 5. Evidence that this exposed cytoplasmic sequence contributes to a functional SH2-like domain is provided by observations that: (i) it contains the most conserved sequence of SH2 domains, GSFLVR; (ii) it binds the tyrosine phosphorylated cytoplasmic domain of band 3 (cdb3-PO4) with Kd = 14 nM; (iii) binding of cdb3-PO4 to erythrocyte membranes is inhibited both by antibodies against the SH2 signature sequence and dephosphorylation of cdb3-PO4; (iv) label transfer experiments demonstrate the covalent transfer of photoactivatable biotin from isolated cdb3-PO4 (but not cdb3) to band 3 in erythrocyte membranes; and (v) phosphorylation-induced binding of cdb3-PO4 to the membrane-spanning domain of band 3 in intact cells causes global changes in membrane properties, including (i) displacement of a glycolytic enzyme complex from the membrane, (ii) inhibition of anion transport, and (iii) rupture of the band 3-ankyrin bridge connecting the spectrin-based cytoskeleton to the membrane. Because SH2-like motifs are not retrieved by normal homology searches for SH2 domains, but can be found in many tyrosine kinase-regulated transport proteins using modified search programs, we suggest that related cases of membrane transport proteins containing similar motifs are widespread in nature where they participate in regulation of cell properties.


Asunto(s)
Proteína 1 de Intercambio de Anión de Eritrocito/genética , Eritrocitos/química , Dominios y Motivos de Interacción de Proteínas/genética , Dominios Homologos src/genética , Proteína 1 de Intercambio de Anión de Eritrocito/química , Sitios de Unión , Secuencia Conservada/genética , Citoplasma/química , Citoplasma/genética , Citoesqueleto/química , Citoesqueleto/genética , Membrana Eritrocítica/genética , Membrana Eritrocítica/metabolismo , Eritrocitos/metabolismo , Modelos Moleculares , Fosforilación , Unión Proteica , Estructura Secundaria de Proteína
5.
Fish Shellfish Immunol ; 43(2): 427-35, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25634257

RESUMEN

The type I interferon (IFN) response has been shown to be crucial for the survival of zebrafish larvae infected with nervous necrosis virus (NNV). Teleost type I IFNs can be divided into two groups, based on their cysteine content. While teleost group I IFNs have been extensively studied in terms of their regulation and anti-viral properties, the characteristics of teleost group II IFNs have been relatively unexplored. In this study, we describe the mechanism by which group II IFNs are activated in response to NNV infection in a zebrafish cell line, by focusing on the relationship between type I IFNs and pattern recognition receptors. Expression profile analysis of infected cells by microarray and qPCR revealed signaling activation of two pattern recognition receptors (PRRs): RIG-I like receptors (RLRs) and MyD88-dependent Toll-like receptors (TLRs). Knockdown of retinoic acid-inducible gene I (RIG-I) specifically repressed induction of group II IFNs (IFNϕ2, IFNϕ3) by NNV infection. Furthermore, Ingenuity Pathway Analysis (IPA) was used to demonstrate that RIG-I knockdown results in down-regulation of the inflammatory response in NNV-infected cells. Taken together, our results indicate that RIG-I plays an essential role in zebrafish group II type I IFN induction and the inflammatory response to NNV infection.


Asunto(s)
Enfermedades de los Peces/inmunología , Interferón Tipo I/genética , Nodaviridae/fisiología , Infecciones por Virus ARN/veterinaria , Receptores de Reconocimiento de Patrones/genética , Proteínas de Pez Cebra/genética , Pez Cebra , Animales , Regulación hacia Abajo , Enfermedades de los Peces/virología , Interferón Tipo I/metabolismo , Infecciones por Virus ARN/inmunología , Infecciones por Virus ARN/virología , Receptores de Reconocimiento de Patrones/metabolismo , Transducción de Señal , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo , Proteínas de Pez Cebra/metabolismo
6.
Mar Drugs ; 14(1): 2, 2015 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-26703631

RESUMEN

Pardaxin (H-GFFALIPKIISSPLFKTLLSAVGSALSSSGGQE-OH), a 33-amino-acid polypeptide, is an antimicrobial peptide (AMP) isolated from the marine fish species Pardachirus marmoratus. Pardaxin shows antibacterial and antitumor activities. However, pardaxin-induced inhibition of oral cancer and the mechanism of tumor reduction in buccal pouch carcinogenesis after pardaxin painting remain undetermined. Additionally, the toxic effects of pardaxin on normal tissue remain unclear. The present study investigated the anticancer activity of pardaxin in oral squamous cell carcinoma (OSCC) cells in the hamster buccal pouch model with or without 7,12-dimethylbenz[a]anthracene (DMBA) pretreatment. This is the first study to confirm the effects of pardaxin on normal tissue and its nontoxic effects in vivo. Cell viability assays and colony formation tests in OSCC cell lines (SCC-4) demonstrated that pardaxin reduced cell viability in a dose-dependent manner. Immunofluorescence staining of cleaved caspase-3 in SCC-4 cells revealed that expression of activated caspase-3 in SCC-4 cells significantly increased after 24-h treatment with pardaxin. Additionally, a cell cycle analysis indicated that pardaxin treatment resulted in the cell cycle arrest of SCC-4 cells in the G2/M phase, thereby limiting cell proliferation. Furthermore, pardaxin treatment substantially alleviated carcinogenesis in the DMBA-induced hamster buccal pouch model by lowering prostaglandin E2 levels. These results suggest that pardaxin is a potential marine drug for adjuvant chemotherapy for human OSCC and oral cancer.


Asunto(s)
Antineoplásicos/farmacología , Venenos de los Peces/farmacología , Animales , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Carcinoma de Células Escamosas/tratamiento farmacológico , Línea Celular Tumoral/efectos de los fármacos , Cricetinae , Modelos Animales de Enfermedad , Venenos de los Peces/química , Venenos de los Peces/uso terapéutico , Humanos , Técnicas In Vitro , Ratones , Neoplasias de la Boca/tratamiento farmacológico
7.
Hepatology ; 56(6): 2268-76, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22729936

RESUMEN

UNLABELLED: The mechanisms that mediate the initiation and development of intrahepatic cholangiocarcinoma (ICC) associated with hepatitis B and C virus (HBV and HCV, respectively) infection remain largely unclear. In this study we conditionally coexpressed hepatitis B virus X (HBx) and hepatitis C virus core (HCP) proteins in zebrafish livers, which caused fibrosis and consequently contributed to ICC formation at the age of 3 months. Suppressing the transgene expression by doxycycline (Dox) treatment resulted in the loss of ICC formation. The biomarker networks of zebrafish ICC identified by transcriptome sequencing and analysis were also frequently involved in the development of human neoplasms. The profiles of potential biomarker genes of zebrafish ICC were similar to those of human cholangiocarcinoma. Our data also showed that the pSmad3L oncogenic pathway was activated in HBx and HCP-induced ICC and included phosphorylation of p38 mitogen-activated proteinbase (MAPK) and p44/42 mitogen-activated protein kinase (ERK1/2), indicating the association with transforming growth factor beta 1 (TGF-ß1) signaling pathway in ICC. Bile duct proliferation, fibrosis, and ICC were markedly reduced by knockdown of TGF-ß1 by in vivo morpholinos injections. CONCLUSION: These results reveal that TGF-ß1 plays an important role in HBx- and HCP-induced ICC development. This in vivo model is a potential approach to study the molecular events of fibrosis and ICC occurring in HBV and HCV infection.


Asunto(s)
Neoplasias de los Conductos Biliares/genética , Conductos Biliares Intrahepáticos , Colangiocarcinoma/genética , Modelos Animales de Enfermedad , Hepacivirus , Transactivadores/genética , Proteínas del Núcleo Viral/genética , Pez Cebra , Animales , Animales Modificados Genéticamente , Antibacterianos/farmacología , Neoplasias de los Conductos Biliares/patología , Colangiocarcinoma/patología , Factor de Crecimiento del Tejido Conjuntivo/genética , Ciclina D1/genética , Doxiciclina/farmacología , Expresión Génica/efectos de los fármacos , Sistema de Señalización de MAP Quinasas , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Smad2/genética , Proteína smad3/genética , Factor de Crecimiento Transformador beta1/genética , Regulación hacia Arriba , Factor A de Crecimiento Endotelial Vascular/genética , Proteínas Reguladoras y Accesorias Virales , Proteínas de Pez Cebra/genética , Proteínas Quinasas p38 Activadas por Mitógenos/genética
8.
J Biol Chem ; 285(52): 41001-9, 2010 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-20961855

RESUMEN

The mechanism that regulates embryonic liver morphogenesis remains elusive. Progranulin (PGRN) is postulated to play a critical role in regulating pathological liver growth. Nevertheless, the exact regulatory mechanism of PGRN in relation to its functional role in embryonic liver development remains to be elucidated. In our study, the knockdown of progranulin A (GrnA), an orthologue of mammalian PGRN, using antisense morpholinos resulted in impaired liver morphogenesis in zebrafish (Danio rerio). The vital role of GrnA in hepatic outgrowth and not in liver bud formation was further confirmed using whole-mount in situ hybridization markers. In addition, a GrnA deficiency was also found to be associated with the deregulation of MET-related genes in the neonatal liver using a microarray analysis. In contrast, the decrease in liver size that was observed in grnA morphants was avoided when ectopic MET expression was produced by co-injecting met mRNA and grnA morpholinos. This phenomenon suggests that GrnA might play a role in liver growth regulation via MET signaling. Furthermore, our study has shown that GrnA positively modulates hepatic MET expression both in vivo and in vitro. Therefore, our data have indicated that GrnA plays a vital role in embryonic liver morphogenesis in zebrafish. As a result, a novel link between PGRN and MET signaling is proposed.


Asunto(s)
Péptidos y Proteínas de Señalización Intercelular/metabolismo , Hígado/embriología , Organogénesis/fisiología , Proteínas Proto-Oncogénicas c-met/biosíntesis , Transducción de Señal/fisiología , Proteínas de Pez Cebra/metabolismo , Pez Cebra/embriología , Animales , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/fisiología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/fisiología , Péptidos y Proteínas de Señalización Intercelular/genética , Oligorribonucleótidos Antisentido/genética , Oligorribonucleótidos Antisentido/farmacología , Organogénesis/efectos de los fármacos , Proteínas Proto-Oncogénicas c-met/genética , Transducción de Señal/efectos de los fármacos , Pez Cebra/genética , Proteínas de Pez Cebra/genética
9.
Transgenic Res ; 20(1): 73-83, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20373020

RESUMEN

Multiple advantages-including the short generation time, large numbers of fertilized eggs, low cost of cultivation and easy maintenance favor the use of fish as bioreactors for the production of pharmaceutical proteins. In the present study, zebrafish eggs were used as bioreactors to produce mature tilapia insulin-like growth factors (IGFs) proteins using the oocyte-specific zona pellucida (zp3) promoter. The chimeric expression plasmids, pT2-ZP-tIGFs-IRES-hrGFP, in which hrGFP was used as reporter of tilapia IGFs expression, were designed to established Tg (ZP:tIGFs:hrGFP) transgenic lines for the expression of tilapia IGF-1 and IGF-2. Recombinant tilapia IGF-1 and IGF-2 were expressed as soluble forms in cytoplasm of fertilized eggs. The content level of tilapia IGF-1 and IGF-2 were 6.5 and 5.0% of the soluble protein, respectively. Using a simple Ni-NTA affinity chromatography purification process, 0.58 and 0.49 mg of purified tilapia IGF-1 and IGF-2 were obtained, respectively, from 650 fertilized eggs. The biological activity of the purified tilapia IGF-1 and IGF-2 was confirmed via a colorimetric bioassay to monitor the growth stimulation of zebrafish embryonic cells (ZF4), tilapia ovary cells (TO-2) and human osteosarcoma epithelial cells (U2OS). These results demonstrate that the use of zebrafish eggs as bioreactors is a promising approach for the production of biological recombinant proteins.


Asunto(s)
Oocitos/metabolismo , Somatomedinas/biosíntesis , Tilapia/metabolismo , Pez Cebra/genética , Animales , Animales Modificados Genéticamente , Reactores Biológicos , Línea Celular , Humanos , Factor I del Crecimiento Similar a la Insulina/biosíntesis , Factor I del Crecimiento Similar a la Insulina/química , Factor II del Crecimiento Similar a la Insulina/biosíntesis , Factor II del Crecimiento Similar a la Insulina/química , Oocitos/citología , Óvulo/citología , Óvulo/metabolismo , Proteínas Recombinantes/biosíntesis , Somatomedinas/química , Tilapia/genética , Pez Cebra/crecimiento & desarrollo , Zona Pelúcida/metabolismo
10.
Sci Transl Med ; 12(567)2020 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-33115948

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a lethal disease with an average life expectancy of 3 to 5 years. IPF is characterized by progressive stiffening of the lung parenchyma due to excessive deposition of collagen, leading to gradual failure of gas exchange. Although two therapeutic agents have been approved from the FDA for IPF, they only slow disease progression with little impact on outcome. To develop a more effective therapy, we have exploited the fact that collagen-producing myofibroblasts express a membrane-spanning protein, fibroblast activation protein (FAP), that exhibits limited if any expression on other cell types. Because collagen-producing myofibroblasts are only found in fibrotic tissues, solid tumors, and healing wounds, FAP constitutes an excellent marker for targeted delivery of drugs to tissues undergoing pathologic fibrosis. We demonstrate here that a low-molecular weight FAP ligand can be used to deliver imaging and therapeutic agents selectively to FAP-expressing cells. Because induction of collagen synthesis is associated with phosphatidylinositol 3-kinase (PI3K) activation, we designed a FAP-targeted PI3K inhibitor that selectively targets FAP-expressing human IPF lung fibroblasts and potently inhibited collagen synthesis. Moreover, we showed that administration of the inhibitor in a mouse model of IPF inhibited PI3K activation in fibrotic lungs, suppressed production of hydroxyproline (major building block of collagen), reduced collagen deposition, and increased mouse survival. Collectively, these studies suggest that a FAP-targeted PI3K inhibitor might be promising for treating IPF.


Asunto(s)
Fibrosis Pulmonar Idiopática , Fosfatidilinositol 3-Quinasas , Animales , Fibroblastos , Fibrosis Pulmonar Idiopática/tratamiento farmacológico , Pulmón , Ratones , Modelos Teóricos , Serina-Treonina Quinasas TOR
11.
EMBO Mol Med ; 12(8): e12034, 2020 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-32597014

RESUMEN

Fibrotic diseases cause organ failure that lead to ~45% of all deaths in the United States. Activated macrophages stimulate fibrosis by secreting cytokines that induce fibroblasts to synthesize collagen and extracellular matrix proteins. Although suppression of macrophage-derived cytokine production can halt progression of fibrosis, therapeutic agents that prevent release of these cytokines (e.g., TLR7 agonists) have proven too toxic to administer systemically. Based on the expression of folate receptor ß solely on activated myeloid cells, we have created a folate-targeted TLR7 agonist (FA-TLR7-54) that selectively accumulates in profibrotic macrophages and suppresses fibrosis-inducing cytokine production. We demonstrate that FA-TLR7-54 reprograms M2-like fibrosis-inducing macrophages into fibrosis-suppressing macrophages, resulting in dramatic declines in profibrotic cytokine release, hydroxyproline biosynthesis, and collagen deposition, with concomitant increases in alveolar airspaces. Although nontargeted TLR7-54 is lethal at fibrosis-suppressing doses, FA-TLR7-54 halts fibrosis without evidence of toxicity. Taken together, FA-TLR7-54 is shown to constitute a novel and potent approach for treating fibrosis without causing dose-limiting systemic toxicities.


Asunto(s)
Bleomicina , Fibrosis Pulmonar , Animales , Fibroblastos , Macrófagos , Macrófagos Alveolares , Ratones , Ratones Endogámicos C57BL , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/tratamiento farmacológico
12.
Sci Total Environ ; 599-600: 94-97, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28467913

RESUMEN

UV (Ultraviolet)-based treatment has been demonstrated to be effective for removal of some disinfection byproducts (DBPs) and to be beneficial for reduction of genotoxicity and cytotoxicity in chlorinated water. However, to a large extent, UV-induced effects on chemistry and toxicology have been treated as a black box, in the sense that little or no UV dose-dependent behavior has been reported. To address this issue, the effects of UV254 irradiation on 1,4-dibenzoquinone (BQ), 2,6-dichloro-1,4-benzoquinone (DCBQ), and chlorocreatinine (Cl-Cre) as model DBPs were examined, both in terms of photodegradation and cytotoxicity. These compounds have been identified as DBPs that are relevant in swimming pool settings; however, these compounds will be relevant in other water treatment settings, including drinking water production and wastewater reuse. UV254 irradiation was shown to promote photodecay of all three compounds. However, for BQ and DCBQ, the corresponding cytotoxicity of the UV-irradiated samples remained essentially unchanged, even when the compound was completely photodegraded. These results indicate that the photodegradation products of BQ and DCBQ carry similar cytotoxicity as their respective parent compounds. On the other hand, UV254-irradiation of Cl-Cre yielded a decrease in cytotoxicity that correlated with photodechlorination of Cl-Cre. These experiments also demonstrated a reduction in cytotoxicity in connection with photodechlorination of an N-chlorinated organic compound. Overall, the results of these experiments indicate the importance of defining products of UV photodecay processes, both in terms of chemistry and toxicity; these attributes are expected to be important in many UV-based applications, including potable water production, water reuse, and recreational water settings.

13.
Oncotarget ; 8(30): 49869-49881, 2017 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-28562331

RESUMEN

Overexpression of the GLI1 gene has frequently been found in various cancer types, particularly in brain tumors, in which aberrant GLI1 induction promotes cancer cell growth. Therefore, identifying the molecular players controlling GLI1 expression is of clinical importance. Previously, we reported that AMPK directly phosphorylated and destabilized GLI1, resulting in the suppression of the Hedgehog signaling pathway. The current study not only demonstrates that AMPK inhibits GLI1 nuclear localization, but further reveals that ß-TrCP plays an essential role in AMPK-induced GLI1 degradation. We found that activation of AMPK promotes the interaction between ß-TrCP and GLI1, and induces ß-TrCP-mediated GLI1-ubiquitination and degradation. Inhibiting AMPK activity results in the dissociation of the ß-TrCP and GLI1 interaction, and diminishes ß-TrCP-mediated-GLI1 ubiquitination and degradation. On GLI1, substitution of AMPK phosphorylation sites to aspartic acid (GLI13E) results in stronger binding affinity of GLI1 with ß-TrCP, accompanied by enhanced GLI1 ubiquitination and later degradation. In contrast, the GLI1 alanine mutant (GLI13A) shows weaker binding with ß-TrCP, which is accompanied by reduced ß-TrCP-mediated ubiquitination and degradation. Together, these results demonstrate that AMPK regulates GLI1 interaction with ß-TrCP by phosphorylating GLI1 and thus both post-translational modifications by AMPK and ß-TrCP ultimately impact GLI1 degradation.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Transducción de Señal , Proteína con Dedos de Zinc GLI1/metabolismo , Proteínas con Repetición de beta-Transducina/metabolismo , Transporte Activo de Núcleo Celular , Animales , Línea Celular Tumoral , Proliferación Celular , Expresión Génica , Humanos , Ratones , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Fosforilación , Transporte de Proteínas , Proteolisis , Ubiquitinación , Proteína con Dedos de Zinc GLI1/genética
14.
PLoS One ; 12(5): e0177887, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28531199

RESUMEN

MicroRNAs (miRs) are mRNA-regulatory molecules that fine-tune gene expression and modulate both processes of development and tumorigenesis. Our previous studies identified progranulin A (GrnA) as a growth factor which induces zebrafish hepatic outgrowth through MET signaling. We also found that miR-145 is one of potential fine-tuning regulators of GrnA involved in embryonic hepatic outgrowth. The low level of miR-145 seen in hepatocarinogenesis has been shown to promote pathological liver growth. However, little is known about the regulatory mechanism of miR-145 in embryonic liver development. In this study, we demonstrate a significant decrease in miR-145 expression during hepatogenesis. We modulate miR-145 expression in zebrafish embryos by injection with a miR-145 mimic or a miR-145 hairpin inhibitor. Altered embryonic liver outgrowth is observed in response to miR-145 expression modulation. We also confirm a critical role of miR-145 in hepatic outgrowth by using whole-mount in situ hybridization. Loss of miR-145 expression in embryos results in hepatic cell proliferation, and vice versa. Furthermore, we demonstrate that GrnA is a target of miR-145 and GrnA-induced MET signaling is also regulated by miR-145 as determined by luciferase reporter assay and gene expression analysis, respectively. In addition, co-injection of GrnA mRNA with miR-145 mimic or MO-GrnA with miR-145 inhibitor restores the liver defects caused by dysregulation of miR-145 expression. In conclusion, our findings suggest an important role of miR-145 in regulating GrnA-dependent hepatic outgrowth in zebrafish embryonic development.


Asunto(s)
Péptidos y Proteínas de Señalización Intercelular/genética , Hígado/crecimiento & desarrollo , MicroARNs/genética , Proteínas de Pez Cebra/genética , Pez Cebra/embriología , Animales , Línea Celular , Proliferación Celular , Regulación del Desarrollo de la Expresión Génica , Hepatocitos/citología , Tamaño de los Órganos , Transducción de Señal , Pez Cebra/genética
15.
Cell Rep ; 12(4): 599-609, 2015 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-26190112

RESUMEN

The Hedgehog (Hh) pathway regulates cell differentiation and proliferation during development by controlling the Gli transcription factors. Cell fate decisions and progression toward organ and tissue maturity must be coordinated, and how an energy sensor regulates the Hh pathway is not clear. AMP-activated protein kinase (AMPK) is an important sensor of energy stores and controls protein synthesis and other energy-intensive processes. AMPK is directly responsive to intracellular AMP levels, inhibiting a wide range of cell activities if ATP is low and AMP is high. Thus, AMPK can affect development by influencing protein synthesis and other processes needed for growth and differentiation. Activation of AMPK reduces GLI1 protein levels and stability, thus blocking Sonic-hedgehog-induced transcriptional activity. AMPK phosphorylates GLI1 at serines 102 and 408 and threonine 1074. Mutation of these three sites into alanine prevents phosphorylation by AMPK. This leads to increased GLI1 protein stability, transcriptional activity, and oncogenic potency.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Meduloblastoma/metabolismo , Procesamiento Proteico-Postraduccional , Factores de Transcripción/metabolismo , Células 3T3 , Secuencia de Aminoácidos , Animales , Línea Celular Tumoral , Células HEK293 , Humanos , Ratones , Datos de Secuencia Molecular , Fosforilación , Estabilidad Proteica , Factores de Transcripción/química , Pez Cebra , Proteína con Dedos de Zinc GLI1
16.
Sci Rep ; 3: 1176, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23378909

RESUMEN

Myogenic progenitor cell (MPC) is responsible for postembryonic muscle growth and regeneration. Progranulin (PGRN) is a pluripotent growth factor that is correlated with neuromuscular disease, which is characterised by denervation, leading to muscle atrophy with an abnormal quantity and functional ability of MPC. However, the role of PGRN in MPC biology has yet to be elucidated. Here, we show that knockdown of zebrafish progranulin A (GrnA) resulted in a reduced number of MPC and impaired muscle growth. The decreased number of Pax7-positive MPCs could be restored by the ectopic expression of GrnA or MET. We further confirmed the requirement of GrnA in MPC activation during muscle regeneration by knockdown and transgenic line with muscle-specific overexpression of GrnA. In conclusion, we demonstrate a critical role for PGRN in the maintenance of MPC and suggest that muscle atrophy under PGRN loss may begin with MPC during postembryonic myogenesis.


Asunto(s)
Péptidos y Proteínas de Señalización Intercelular/metabolismo , Desarrollo de Músculos/fisiología , Músculo Esquelético/metabolismo , Regeneración/fisiología , Células Madre/metabolismo , Proteínas de Pez Cebra/metabolismo , Animales , Animales Modificados Genéticamente/crecimiento & desarrollo , Apoptosis , Proliferación Celular , Proteínas Cardiotóxicas de Elápidos/toxicidad , Regulación de la Expresión Génica/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Péptidos y Proteínas de Señalización Intercelular/genética , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/patología , Factor de Transcripción PAX7/metabolismo , Proteínas Proto-Oncogénicas c-met/genética , Proteínas Proto-Oncogénicas c-met/metabolismo , Células Madre/citología , Pez Cebra/crecimiento & desarrollo , Proteínas de Pez Cebra/antagonistas & inhibidores , Proteínas de Pez Cebra/genética
17.
FEBS Lett ; 586(19): 3485-92, 2012 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-22967900

RESUMEN

It is well known that growth hormone (GH)-induced IGF-1 signaling plays a dominant role in postnatal muscle growth. Our previous studies have identified a growth factor, progranulin (PGRN), that is co-induced with IGF-1 upon GH administration. This result prompted us to explore the function of PGRN and its association with IGF-1. In the present study, we demonstrated that, similar to IGF-1, PGRN can promote C2C12 myotube hypertrophy via the PI(3)K/Akt/mTOR pathway. Moreover, PGRN can rescue the muscle atrophy phenotypes in C2C12 myotube when IGF-1 signaling is blocked. This result shows that PGRN can substitute for IGF-1 signaling in the regulation of muscle growth. Our findings provide new insights into IGF-1-modulated complicated networks that regulate muscle growth.


Asunto(s)
Factor I del Crecimiento Similar a la Insulina/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Animales , Secuencia de Bases , Línea Celular , Cartilla de ADN/genética , Granulinas , Hipertrofia , Factor I del Crecimiento Similar a la Insulina/antagonistas & inhibidores , Factor I del Crecimiento Similar a la Insulina/genética , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intercelular/farmacología , Ratones , Modelos Biológicos , Desarrollo de Músculos/fisiología , Fibras Musculares Esqueléticas/patología , Atrofia Muscular/tratamiento farmacológico , Atrofia Muscular/metabolismo , Atrofia Muscular/patología , Mioblastos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Progranulinas , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
18.
Gen Comp Endocrinol ; 150(2): 212-8, 2007 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-17011560

RESUMEN

Like IGF-I, progranulin (pgrn) is a growth factor involved in tumorigenesis and wound healing. We report here the identification and characterization of pgrn cDNA in tilapia and the regulation of its expression by growth hormone (GH). The tilapia pgrn cDNA was cloned by RT-PCR amplification, using gene specific oligonucleotides as amplification primers. The cDNA contains an open reading frame encoding a peptide of 206 amino acid residues (aa) that contains a presumptive signal peptide (23 aa) and two repeat units of granulin (grn, 51 and 52 aa, respectively) franked by a GAP of 49 aa and the carboxyl terminus with 31 aa. The two predicted grn peptides are arranged in tandem repeats interrupted by a GAP peptide. RT-PCR analysis revealed that high levels of prgn mRNA were present in several tissues such as spleen, gastric cecum, intestine, fat tissue, gill, kidney, eye and pancreas, and lower levels in liver, muscle, heart, brain, skin and stomach. Administration of a single dose (500 ng/g body weight) of recombinant seabream growth hormone (rbGH) by intraperitoneal (ip) injection into one-month-old tilapia resulted in an obvious increase of IGF-I and pgrn mRNA (2.7-fold and 2.5-fold, respectively) in the liver at three hours post-GH treatment. The peptide levels of pgrn in the liver of GH-treated fish also were substantially induced over controls at 12h post-GH treatment as detected by western immuno-blot analysis. The co-induction of IGF-I and pgrn following GH treatment may suggest the involvement of pgrn in GH regulated growth in tilapia.


Asunto(s)
Proteínas de Peces/biosíntesis , Factor I del Crecimiento Similar a la Insulina/biosíntesis , Péptidos y Proteínas de Señalización Intercelular/biosíntesis , Hígado/fisiología , ARN Mensajero/biosíntesis , Tilapia/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting/veterinaria , Western Blotting/veterinaria , Clonación Molecular , Proteínas de Peces/genética , Regulación de la Expresión Génica , Factor I del Crecimiento Similar a la Insulina/genética , Péptidos y Proteínas de Señalización Intercelular/genética , Hígado/metabolismo , Datos de Secuencia Molecular , Progranulinas , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Alineación de Secuencia , Tilapia/metabolismo
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