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This study describes the novel development of quaternized cassava starch (Q-CS) with antimicrobial and antiviral properties, particularly effective against the MHV-3 coronavirus. The preparation of Q-CS involved the reaction of cassava starch (CS) with glycidyltrimethylammonium chloride (GTMAC) in an alkaline solution. Q-CS physicochemical properties were determined by FTIR, NMR, elemental analysis, zeta potential, TGA, and moisture sorption. FTIR and NMR spectra confirmed the introduction of cationic groups in the CS structure. The elemental analysis revealed a degree of substitution (DS) of 0.552 of the cationic reagent on the hydroxyl groups of CS. Furthermore, Q-CS exhibited a positive zeta potential value (+28.6 ± 0.60 mV) attributed to the high positive charge density shown by the quaternary ammonium groups. Q-CS demonstrated lower thermal stability and higher moisture sorption compared to CS. The antimicrobial activity of Q-CS was confirmed against Escherichia coli (MIC = 0.156 mg mL-1) and Staphylococcus aureus (MIC = 0.312 mg mL-1), along with a remarkable ability to inactivate 99% of MHV-3 coronavirus after only 1 min of direct contact. Additionally, Q-CS showed high cell viability (close to 100%) and minimal cytotoxicity effects, guaranteeing its safe use. Therefore, these findings indicate the potential use of Q-CS as a raw material for antiseptic biomaterials.
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Compuestos de Amonio , Coronavirus , Manihot , Manihot/química , Staphylococcus aureus , Almidón/químicaRESUMEN
BACKGROUND: Understanding the molecular underpinnings of phenotypic variations is critical for enhancing poultry breeding programs. The Brazilian broiler (TT) and laying hen (CC) lines exhibit striking differences in body weight, growth potential, and muscle mass. Our work aimed to compare the global transcriptome of wing and pectoral tissues during the early development (days 2.5 to 3.5) of these chicken lines, unveiling disparities in gene expression and regulation. RESULTS: Different and bona-fide transcriptomic profiles were identified for the compared lines. A similar number of up- and downregulated differentially expressed genes (DEGs) were identified, considering the broiler line as a reference. Upregulated DEGs displayed an enrichment of protease-encoding genes, whereas downregulated DEGs exhibited a prevalence of receptors and ligands. Gene Ontology analysis revealed that upregulated DEGs were mainly associated with hormone response, mitotic cell cycle, and different metabolic and biosynthetic processes. In contrast, downregulated DEGs were primarily linked to communication, signal transduction, cell differentiation, and nervous system development. Regulatory networks were constructed for the mitotic cell cycle and cell differentiation biological processes, as their contrasting roles may impact the development of distinct postnatal traits. Within the mitotic cell cycle network, key upregulated DEGs included CCND1 and HSP90, with central regulators being NF-κB subunits (RELA and REL) and NFATC2. The cell differentiation network comprises numerous DEGs encoding transcription factors (e.g., HOX genes), receptors, ligands, and histones, while the main regulatory hubs are CREB, AR and epigenetic modifiers. Clustering analyses highlighted PIK3CD as a central player within the differentiation network. CONCLUSIONS: Our study revealed distinct developmental transcriptomes between Brazilian broiler and layer lines. The gene expression profile of broiler embryos seems to favour increased cell proliferation and delayed differentiation, which may contribute to the subsequent enlargement of pectoral tissues during foetal and postnatal development. Our findings pave the way for future functional studies and improvement of targeted traits of economic interest in poultry.
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Pollos , Perfilación de la Expresión Génica , Animales , Femenino , Pollos/genética , Biología Computacional , Transcriptoma , Diferenciación Celular/genéticaRESUMEN
We previously reported that the canonical Wnt signaling pathway is activated during compensatory islet hyperplasia in prediabetic mice. Here, we aimed to expand our knowledge concerning the Wnt signaling partners and modulators involved in this process. We report here that Axin1, Axin2, and DACT1, inhibitors of the canonical Wnt signaling pathway, displayed no change in their expression, while GSK-3ß, a multi-functional kinase that acts as a negative regulator of this pathway as well as affects insulin secretion/action, was up-regulated in hyperplastic islets of prediabetic mice. We also observed that COUP-TFII, a protein that acts positively on Wnt-target genes related to cell proliferation, displays a significant increase in gene expression and protein content and is highly immunolabeled in islet cell nuclei of prediabetic mice compared to control islets. These findings suggest that GSK-3ß and COUP-TFII may play a role in beta-cell dysfunction and hyperplasia during type 2 prediabetes.
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Estado Prediabético , Vía de Señalización Wnt , Animales , Proliferación Celular , Glucógeno Sintasa Quinasa 3 beta/genética , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Hiperplasia , Ratones , Estado Prediabético/genética , Vía de Señalización Wnt/fisiología , beta Catenina/metabolismoRESUMEN
LMO7 is a multifunctional PDZ-LIM protein that can interact with different molecular partners and is found in several intracellular locations. The aim of this work was to shed light on LMO7 evolution, alternative transcripts, protein structure and gene regulation through multiple in silico analyses. We also explored the intracellular distribution of the LMO7 protein in chicken and zebrafish embryonic skeletal muscle cells by means of confocal fluorescence microscopy. Our results revealed a single LMO7 gene in mammals, sauropsids, Xenopus and in the holostean fish spotted gar while two lmo7 genes (lmo7a and lmo7b) were identified in teleost fishes. In addition, several different transcripts were predicted for LMO7 in human and in major vertebrate model organisms (mouse, chicken, Xenopus and zebrafish). Bioinformatics tools revealed several structural features of the LMO7 protein including intrinsically disordered regions. We found the LMO7 protein in multiple intracellular compartments in chicken and zebrafish skeletal muscle cells, such as membrane adhesion sites and the perinuclear region. Curiously, the LMO7 protein was detected within the nuclei of muscle cells in chicken but not in zebrafish. Our data showed that a conserved regulatory element may be related to muscle-specific LMO7 expression. Our findings uncover new and important information about LMO7 and open new challenges to understanding how the diverse regulation, structure and distribution of this protein are integrated into highly complex vertebrate cellular milieux, such as skeletal muscle cells.
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Evolución Molecular , Proteínas con Dominio LIM/metabolismo , Modelos Moleculares , Fibras Musculares Esqueléticas/metabolismo , Factores de Transcripción/metabolismo , Empalme Alternativo , Secuencia de Aminoácidos , Animales , Pollos , Simulación por Computador , Humanos , Proteínas con Dominio LIM/genética , Ratones , Modelos Animales , Conformación Proteica , Factores de Transcripción/genética , Pez CebraRESUMEN
Vertebrate skeletal muscle development and repair relies on the precise control of Wnt signaling. Dact1 (Dapper/Frodo) is an important modulator of Wnt signaling, interacting with key components of the various Wnt transduction pathways. Here, we characterized Dact1 mRNA and protein expression in chicken and mouse fetal muscles in vivo and during the differentiation of chick primary and mouse C2C12 myoblasts in vitro. We also performed in silico analysis to investigate Dact1 gene expression in human myopathies, and evaluated the Dact1 protein structure to seek an explanation for the accumulation of Dact1 protein aggregates in the nuclei of myogenic cells. Our results show for the first time that in both chicken and mouse, Dact1 is expressed during myogenesis, with a strong upregulation as cells engage in terminal differentiation, cell cycle withdrawal and cell fusion. In humans, Dact1 expression was found to be altered in specific muscle pathologies, including muscular dystrophies. Our bioinformatic analyses of Dact1 proteins revealed long intrinsically disordered regions, which may underpin the ability of Dact1 to interact with its many partners in the various Wnt pathways. In addition, we found that Dact1 has strong propensity for liquid-liquid phase separation, a feature that explains its ability to form nuclear aggregates and points to a possible role as a molecular 'on'-'off' switch. Taken together, our data suggest Dact1 as a candidate, multi-faceted regulator of amniote myogenesis with a possible pathophysiological role in human muscular diseases.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Regulación del Desarrollo de la Expresión Génica , Desarrollo de Músculos , Músculo Esquelético/metabolismo , Enfermedades Musculares/metabolismo , Mioblastos/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Diferenciación Celular , Núcleo Celular/metabolismo , Proliferación Celular , Pollos , Femenino , Humanos , Ratones , Músculo Esquelético/citología , Enfermedades Musculares/patología , Mioblastos/citología , Proteínas Nucleares/genética , Proteínas de Unión al ARN/genéticaRESUMEN
Envenoming caused by snakebites is a very important neglected tropical disease worldwide. The myotoxic phospholipases present in the bothropic venom disrupt the sarcolemma and compromise the mechanisms of energy production, leading to myonecrosis. Photobiomodulation therapy (PBMT) has been used as an effective tool to treat diverse cases of injuries, such as snake venom-induced myonecrosis. Based on that, the aim of this study was to analyze the effects of PBMT through low-level laser irradiation (904 nm) on the muscle regeneration after the myonecrosis induced by Bothrops jararacussu snake venom (Bjssu) injection, focusing on myogenic regulatory factors expression, such as Pax7, MyoD, and Myogenin (MyoG). Male Swiss mice (Mus musculus), 6-8-week-old, weighing 22 ± 3 g were used. Single sub-lethal Bjssu dose or saline was injected into the right mice gastrocnemius muscle. At 3, 24, 48, and 72 h after injections, mice were submitted to PBMT treatment. When finished the periods of 48 and 72 h, mice were euthanized and the right gastrocnemius were collected for analyses. We observed extensive inflammatory infiltrate in all the groups submitted to Bjssu injections. PBMT was able to reduce the myonecrotic area at 48 and 72 h after envenomation. There was a significant increase of MyoG mRNA expression at 72 h after venom injection. The data suggest that beyond the protective effect promoted by PBMT against Bjssu-induced myonecrosis, the low-level laser irradiation was able to stimulate the satellite cells, thus enhancing the muscle repair by improving myogenic differentiation.
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Bothrops , Venenos de Crotálidos/toxicidad , Regulación de la Expresión Génica/efectos de la radiación , Terapia por Láser , Miogenina/metabolismo , Necrosis/terapia , Animales , Diferenciación Celular , Terapia por Luz de Baja Intensidad , Masculino , Ratones , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/efectos de la radiación , Miogenina/genéticaRESUMEN
Myostatin (MSTN) is one of the key factors regulating myogenesis. Because of its role as a negative regulator of muscle mass deposition, much interest has been given to its protein and, in recent years, several studies have analysed MSTN gene regulation. This review discusses the MSTN gene promoter, focusing on its structure in several animal species, both vertebrate and invertebrate. We report the important binding sites considering their degree of phylogenetic conservation and roles they play in the promoter activity. Finally, we discuss recent studies focusing on MSTN gene regulation via promoter manipulation and the potential applications they have both in medicine and agriculture.
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Tendon injuries represent a clinical challenge in regenerative medicine because their natural repair process is complex and inefficient. The high incidence of tendon injuries is frequently associated with sports practice, aging, tendinopathies, hypertension, diabetes mellitus, and the use of corticosteroids. The growing interest of scientists in using adipose-derived mesenchymal stem cells (ADMSC) in repair processes seems to be mostly due to their paracrine and immunomodulatory effects in stimulating specific cellular events. ADMSC activity can be influenced by GDF-5, which has been successfully used to drive tenogenic differentiation of ADMSC in vitro. Thus, we hypothesized that the application of ADMSC in isolation or in association with GDF-5 could improve Achilles tendon repair through the regulation of important remodeling genes expression. Lewis rats had tendons distributed in four groups: Transected (T), transected and treated with ADMSC (ASC) or GDF-5 (GDF5), or with both (ASC+GDF5). In the characterization of cells before application, ADMSC expressed the positive surface markers, CD90 (90%) and CD105 (95%), and the negative marker, CD45 (7%). ADMSC were also differentiated in chondrocytes, osteoblast, and adipocytes. On the 14th day after the tendon injury, GFP-ADMSC were observed in the transected region of tendons in the ASC and ASC+GDF5 groups, and exhibited and/or stimulated a similar genes expression profile when compared to the in vitro assay. ADMSC up-regulated Lox, Dcn, and Tgfb1 genes expression in comparison to T and ASC+GDF5 groups, which contributed to a lower proteoglycans arrangement, and to a higher collagen fiber organization and tendon biomechanics in the ASC group. The application of ADMSC in association with GDF-5 down-regulated Dcn, Gdf5, Lox, Tgfb1, Mmp2, and Timp2 genes expression, which contributed to a lower hydroxyproline concentration, lower collagen fiber organization, and to an improvement of the rats' gait 24 h after the injury. In conclusion, although the literature describes the benefic effect of GDF-5 for the tendon healing process, our results show that its application, isolated or associated with ADMSC, cannot improve the repair process of partial transected tendons, indicating the higher effectiveness of the application of ADMSC in injured Achilles tendons. Our results show that the application of ADMSC in injured Achilles tendons was more effective in relation to its association with GDF-5.
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Animal models commonly serve as a bridge between in vitro experiments and clinical applications; however, few physiological processes in adult animals are sufficient to serve as proof-of-concept models for cartilage regeneration. Intriguingly, some rodents, such as young adult mice, undergo physiological connective tissue modifications to birth canal elements such as the pubic symphysis during pregnancy; therefore, we investigated whether the differential expression of cartilage differentiation markers is associated with cartilaginous tissue morphological modifications during these changes. Our results showed that osteochondral progenitor cells expressing Runx2, Sox9, Col2a1 and Dcx at the non-pregnant pubic symphysis proliferated and differentiated throughout pregnancy, giving rise to a complex osteoligamentous junction that attached the interpubic ligament to the pubic bones until labour occurred. After delivery, the recovery of pubic symphysis cartilaginous tissues was improved by the time-dependent expression of these chondrocytic lineage markers at the osteoligamentous junction. This process potentially recapitulates embryologic chondrocytic differentiation to successfully recover hyaline cartilaginous pads at 10 days postpartum. Therefore, we propose that this physiological phenomenon represents a proof-of-concept model for investigating the mechanisms involved in cartilage restoration in adult animals.
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Preñez/fisiología , Sínfisis Pubiana/anatomía & histología , Sínfisis Pubiana/patología , Animales , Antígenos de Diferenciación , Cartílago/patología , Tejido Conectivo/patología , Proteína Doblecortina , Femenino , Regulación del Desarrollo de la Expresión Génica/fisiología , Ligamentos/patología , Ratones , Modelos Animales , Pelvis , Periodo Posparto/metabolismo , EmbarazoRESUMEN
Myostatin (MSTN) is a strong inhibitor of skeletal muscle growth in human and other vertebrates. Its transcription is controlled by a proximal promoter/enhancer (Mstn P/E) containing a TATA box besides CREB, NF-Y, MEIS1 and FXR transcription factor binding sites (TFBSs), which are conserved throughout evolution. The aim of this work was to investigate the role of these TFBSs on Mstn P/E activity and evaluate the potential of their putative ligands as Mstn trans regulators. Mstn P/E mutant constructs were used to establish the role of conserved TFBSs using dual-luciferase assays. Expression analyses were performed by RT-PCR and in situ hybridization in C2C12 myoblasts and E10.5 mouse embryos, respectively. Our results revealed that CREB, NF-Y and MEIS1 sites are required to balance Mstn P/E activity, keeping Mstn transcription within basal levels during myoblast proliferation. Furthermore, our data showed that NF-Y site is essential, although not sufficient, to mediate Mstn P/E transcriptional activity. In turn, CREB and MEIS1 binding sites seem to depend on the presence of NF-Y site to induce Mstn P/E. FXR appears not to confer any effect on Mstn P/E activity, except in the absence of all other conserved TFBS. Accordingly, expression studies pointed to CREB, NF-Y and MEIS1 but not to FXR factors as possible regulators of Mstn transcription in the myogenic context. Altogether, our findings indicated that CREB, NF-Y and MEIS1 conserved sites are essential to control basal Mstn transcription during early myogenesis, possibly by interacting with these or other related factors.
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Miostatina/genética , Miostatina/metabolismo , Animales , Sitios de Unión , Factor de Unión a CCAAT , Proteína de Unión a CREB , Línea Celular , Secuencia Conservada , Humanos , Ratones , Desarrollo de Músculos/genética , Proteína 1 del Sitio de Integración Viral Ecotrópica Mieloide , Mioblastos/metabolismo , Regiones Promotoras Genéticas , Secuencias Reguladoras de Ácidos Nucleicos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transcripción GenéticaRESUMEN
BACKGROUND: DACT genes regulates Wnt as well TGF-ß pathway, and were already associated with hepatocellular and lung cancer. Alterations on Wnt/ß-catenin were associated with head and neck cancer through ß-catenin cytoplasmatic accumulation. OBJECTIVE: The aim of the study was to evaluate DACT1 and DACT2 expression and methylation on oral squamous cell cancer (OSCC). METHODS: 47 samples of salivary rinse and tissue were collected from 29 OSCC and 18 control patients. qMSP and RT-PCR reactions were performed in order to detect hypermethylation and expression of DACT1 and DACT2 genes. Statistical analysis was conducted to evaluate these genes as possible biomarkers for OSCC. RESULTS: As expected man over 60 years old with tobacco and alcohol consumption history were associated with OSCC. There was no statistical difference between groups concerning DACT1 and DACT2 either in promoter hypermethylation or transcript levels. Age was associated with DACT2 promoter hypermethylation, especially over 56 years old. CONCLUSION: Patients older than 56 years old were about 5 times more likely to have DACT2 promoter hypermethylation. These findings could partially explain why older subjects are more prone to carcinogenesis. Wnt/ß-catenin pathway plays an important role in carcinogenesis, and the study of their regulators may help understand malignant transformation.
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Proteínas Adaptadoras Transductoras de Señales/genética , Carcinoma de Células Escamosas/genética , Proteínas Portadoras/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias de Cabeza y Cuello/genética , Neoplasias de la Boca/genética , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Proteínas Adaptadoras Transductoras de Señales/biosíntesis , Factores de Edad , Carcinoma de Células Escamosas/metabolismo , Proteínas Portadoras/biosíntesis , Estudios de Casos y Controles , Línea Celular Tumoral , Metilación de ADN , Epigénesis Genética , Femenino , Neoplasias de Cabeza y Cuello/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/metabolismo , Proteínas de Neoplasias/biosíntesis , Proteínas Nucleares/biosíntesis , Regiones Promotoras Genéticas , Estudios Prospectivos , Carcinoma de Células Escamosas de Cabeza y CuelloRESUMEN
BACKGROUND: Dacts are multi-domain adaptor proteins. They have been implicated in Wnt and Tgfß signaling and serve as a nodal point in regulating many cellular activities. Dact genes have so far only been identified in bony vertebrates. Also, the number of Dact genes in a given species, the number and roles of protein motifs and functional domains, and the overlap of gene expression domains are all not clear. To address these problems, we have taken an evolutionary approach, screening for Dact genes in the animal kingdom and establishing their phylogeny and the synteny of Dact loci. Furthermore, we performed a deep analysis of the various Dact protein motifs and compared the expression patterns of different Dacts. RESULTS: Our study identified previously not recognized dact genes and showed that they evolved late in the deuterostome lineage. In gnathostomes, four Dact genes were generated by the two rounds of whole genome duplication in the vertebrate ancestor, with Dact1/3 and Dact2/4, respectively, arising from the two genes generated during the first genome duplication. In actinopterygians, a further dact4r gene arose from retrotranscription. The third genome duplication in the teleost ancestor, and subsequent gene loss in most gnathostome lineages left extant species with a subset of Dact genes. The distribution of functional domains suggests that the ancestral Dact function lied with Wnt signaling, and a role in Tgfß signaling may have emerged with the Dact2/4 ancestor. Motif reduction, in particular in Dact4, suggests that this protein may counteract the function of the other Dacts. Dact genes were expressed in both distinct and overlapping domains, suggesting possible combinatorial function. CONCLUSIONS: The gnathostome Dact gene family comprises four members, derived from a chordate-specific ancestor. The ability to control Wnt signaling seems to be part of the ancestral repertoire of Dact functions, while the ability to inhibit Tgfß signaling and to carry out specialized, ortholog-specific roles may have evolved later. The complement of Dact genes coexpressed in a tissue provides a complex way to fine-tune Wnt and Tgfß signaling. Our work provides the basis for future structural and functional studies aimed at unraveling intracellular regulatory networks.
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Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Cordados/genética , Evolución Molecular , Transducción de Señal , Animales , Cordados/metabolismo , Humanos , Filogenia , Sintenía , Factor de Crecimiento Transformador beta/metabolismo , Vía de Señalización WntRESUMEN
The epididymis has an important role in the maturation of sperm for fertilization, but little is known about the epididymal molecules involved in sperm modifications during this process. We have previously described the expression pattern for an antigen in epididymal epithelial cells that reacts with the monoclonal antibody (mAb) TRA 54. Immunohistochemical and immunoblotting analyses suggest that the epitope of the epididymal antigen probably involves a sugar moiety that is released into the epididymal lumen in an androgen-dependent manner and subsequently binds to luminal sperm. Using column chromatography, SDS-PAGE with in situ digestion and mass spectrometry, we have identified the protein recognized by mAb TRA 54 in mouse epididymal epithelial cells. The â¼65 kDa protein is part of a high molecular mass complex (â¼260 kDa) that is also present in the sperm acrosomal vesicle and is completely released after the acrosomal reaction. The amino acid sequence of the protein corresponded to that of albumin. Immunoprecipitates with anti-albumin antibody contained the antigen recognized by mAb TRA 54, indicating that the epididymal molecule recognized by mAb TRA 54 is albumin. RT-PCR detected albumin mRNA in the epididymis and fertilization assays in vitro showed that the glycoprotein complex containing albumin was involved in the ability of sperm to recognize and penetrate the egg zona pellucida. Together, these results indicate that epididymal-derived albumin participates in the formation of a high molecular mass glycoprotein complex that has an important role in egg fertilization.
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Albúminas/metabolismo , Epidídimo/metabolismo , Glicoproteínas/metabolismo , Óvulo/metabolismo , Espermatozoides/metabolismo , Animales , Anticuerpos Monoclonales , Electroforesis en Gel de Poliacrilamida , Femenino , Fertilización/fisiología , Immunoblotting , Inmunoprecipitación , Masculino , Ratones , Ratones Endogámicos C57BL , Óvulo/fisiología , Espectrometría de Masa por Ionización de Electrospray , Espermatozoides/fisiologíaRESUMEN
BACKGROUND: Dact gene family encodes multifunctional proteins that are important modulators of Wnt and TGF-ß signaling pathways. Given that these pathways coordinate multiple steps of limb development, we investigated the expression pattern of the two chicken Dact genes (Dact1 and Dact2) from early limb bud up to stages when several tissues are differentiating. RESULTS: During early limb development (HH24-HH30) Dact1 and Dact2 were mainly expressed in the cartilaginous rudiments of the appendicular skeleton and perichondrium, presenting expression profiles related, but distinct. At later stages of development (HH31-HH35), the main sites of Dact1 and Dact2 expression were the developing synovial joints. In this context, Dact1 expression was shown to co-localize with regions enriched in the nuclear ß-catenin protein, such as developing joint capsule and interzone. In contrast, Dact2 expression was restricted to the interzone surrounding the domains of bmpR-1b expression, a TGF-ß receptor with crucial roles during digit morphogenesis. Additional sites of Dact expression were the developing tendons and digit blastemas. CONCLUSIONS: Our data indicate that Dact genes are good candidates to modulate and, possibly, integrate Wnt and TGF-ß signaling during limb development, bringing new and interesting perspectives about the roles of Dact molecules in limb birth defects and human diseases.
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Proteínas Adaptadoras Transductoras de Señales/biosíntesis , Proteínas Aviares/biosíntesis , Regulación del Desarrollo de la Expresión Génica/fisiología , Miembro Posterior/embriología , Proteínas Nucleares/biosíntesis , Factor de Crecimiento Transformador beta/metabolismo , Vía de Señalización Wnt/fisiología , Animales , Embrión de Pollo , Miembro Posterior/citología , Humanos , Membrana Sinovial/citología , Membrana Sinovial/embriologíaRESUMEN
Impairment of pelvic organ support has been described in mice with genetic modifications of the proteins involved in elastogenesis, such as lysyl oxidase-like 1 (LOXL1) and fibulin 5. During pregnancy, elastic fiber-enriched pelvic tissues are modified to allow safe delivery. In addition, the mouse pubic symphysis is remodeled in a hormone-controlled process that entails the modification of the fibrocartilage into an interpubic ligament (IpL) and the relaxation of this ligament. After first parturition, recovery occurs to ensure pelvic tissue homeostasis. Because ligaments are the main supports of the pelvic organs, this study aimed to evaluate elastogenesis in the IpL during mouse pregnancy and postpartum. Accordingly, virgin, pregnant, and postpartum C57BL/6 mice were studied using light, confocal, and transmission electron microscopy as well as Western blots and real-time PCR. Female mice exhibited the separation of the pubic bones and the formation, relaxation, and postpartum recovery of the IpL. By the time the IpL was formed, the elastic fibers had increased in profile length and diameter, and they consisted of small conglomerates of amorphous material distributed among the bundles of microfibrils. Our analyses also indicated that elastin/tropoelastin, fibrillin 1, LOXL1/Loxl1, and fibulin 5 were spatially and temporally regulated, suggesting that these molecules may contribute to the synthesis of new elastic fibers during IpL development. Overall, this work revealed that adult elastogenesis may be important to assure the elasticity of the pelvic girdle during preparation for parturition and postpartum recovery. This finding may contribute to our understanding of pathological processes involving elastogenesis in the reproductive tract.
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Tejido Elástico/metabolismo , Periodo Posparto/metabolismo , Sínfisis Pubiana/metabolismo , Aminoácido Oxidorreductasas/metabolismo , Animales , Tejido Elástico/citología , Elasticidad , Elastina/metabolismo , Proteínas de la Matriz Extracelular/metabolismo , Femenino , Fibrilina-1 , Fibrilinas , Ligamentos/citología , Ligamentos/metabolismo , Ratones , Ratones Endogámicos C57BL , Proteínas de Microfilamentos/metabolismo , Pelvis , Embarazo , Sínfisis Pubiana/citología , Proteínas Recombinantes/metabolismoRESUMEN
Dapper (Dpr) proteins are context-dependent regulators of Wnt and Tgfbeta signaling. However, although inroads into their molecular properties have been made, their expression and biological function are not understood. Searching for avian Dpr genes, we found that the chicken harbors a Dpr1 and a Dpr2 paralogue only. The genes are expressed in distinct patterns at gastrulation, neurulation, and organogenesis stages of development with key expression domains being the posterior primitive streak, anterior node and notochord, presomitic mesoderm (segmental plate), lateral and cardiac mesoderm, limb mesenchyme, and neurogenic placodes for Dpr1, and anterior primitive streak, node, epithelial somites, embryonic muscle stem cells, oral ectoderm and endoderm, neural crest cells, limb ectoderm, and lung buds for Dpr2. Expression overlaps in a few tissues; however, in several tissues, expression is complementary.
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Células Madre Embrionarias/metabolismo , Regulación del Desarrollo de la Expresión Génica , Péptidos y Proteínas de Señalización Intracelular/genética , Mesodermo/metabolismo , Mioblastos/metabolismo , Cresta Neural/metabolismo , Animales , Embrión de Pollo , Embrión no Mamífero/embriología , Embrión no Mamífero/metabolismo , Células Madre Embrionarias/citología , Marcadores Genéticos , Mesodermo/citología , Mioblastos/citología , Cresta Neural/citologíaRESUMEN
Myostatin (Mstn) is a negative regulator of skeletal muscle mass, and Mstn mutations are responsible for the double muscling phenotype observed in many animal species. Moreover, Mstn is a positive regulator of adult muscle stem cell (satellite cell) quiescence, and hence, Mstn is being targeted in therapeutic approaches to muscle diseases. In order to better understand the mechanisms underlying Mstn regulation, we searched for the gene's proximal enhancer and promoter elements, using an evolutionary approach. We identified a 260-bp-long, evolutionary conserved region upstream of tetrapod Mstn and teleost mstn b genes. This region contains binding sites for TATA binding protein, Meis1, NF-Y, and for CREB family members, suggesting the involvement of cAMP in Myostatin regulation. The conserved fragment was able to drive reporter gene expression in C2C12 cells in vitro and in chicken somites in vivo; both normally express Mstn. In contrast, the reporter construct remained silent in the avian neural tube that normally does not express Mstn. This suggests that the identified element serves as a minimal promoter, harboring some spatial specificity. Finally, using bioinformatic approaches, we identified additional genes in the human genome associated with sequences similar to the Mstn proximal promoter/enhancer. Among them are genes important for myogenesis. This suggests that Mstn and these genes may form a synexpression group, regulated by a common signaling pathway.
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Miostatina/genética , Regiones Promotoras Genéticas , Animales , Secuencia de Bases , Sitios de Unión , Elementos de Facilitación Genéticos , Humanos , Datos de Secuencia Molecular , Transcripción GenéticaRESUMEN
In this study, the abundance of IGF-II and bFGF transcripts was estimated in the chicken embryos using the competitive RT-PCR analysis. Significant enhancements in the abundance of IGF-II mRNA were observed at stages HH1 and 5, and a new accumulation in these levels was observed at stage HH18 in comparison to the basal levels. The abundance of bFGF mRNA increased significantly at stages HH18 and 20, followed by an upregulation in the expression of these transcripts at stage HH26. These findings provided important information about the temporal expression pattern of IGF-II and bFGF transcripts in the whole chicken embryos during in ovo development.
Fatores de crescimento coordenam múltiplas vias de sinalização durante o desenvolvimento embrionário. Neste estudo, a abundância de mRNA dos genes IGF-II e bFGF foi estimada em embriões de galinha por análises de RT-PCR competitiva. Aumentos na abundância de mRNA de IGF-II foram observados nos estádios HH1, 5. Os níveis de mRNA de bFGF exibiram aumentos a partir dos estádios HH18 e 20, seguido por uma acentuada redução a níveis basais no estádio HH24 e por um segundo pico na expressão destes transcritos no estádio HH26. Tais descobertas proporcionam importantes informações sobre o padrão de expressão destes fatores de crescimento durante a embriogênese de aves