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1.
J Endocr Soc ; 6(9): bvac109, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37283844

RESUMO

Nongenomic effects of estrogen receptor α (ERα) signaling have been described for decades. Several distinct animal models have been generated previously to analyze the nongenomic ERα signaling (eg, membrane-only ER, and ERαC451A). However, the mechanisms and physiological processes resulting solely from nongenomic signaling are still poorly understood. Herein, we describe a novel mouse model for analyzing nongenomic ERα actions named H2NES knock-in (KI). H2NES ERα possesses a nuclear export signal (NES) in the hinge region of ERα protein resulting in exclusive cytoplasmic localization that involves only the nongenomic action but not nuclear genomic actions. We generated H2NESKI mice by homologous recombination method and have characterized the phenotypes. H2NESKI homozygote mice possess almost identical phenotypes with ERα null mice except for the vascular activity on reendothelialization. We conclude that ERα-mediated nongenomic estrogenic signaling alone is insufficient to control most estrogen-mediated endocrine physiological responses; however, there could be some physiological responses that are nongenomic action dominant. H2NESKI mice have been deposited in the repository at Jax (stock no. 032176). These mice should be useful for analyzing nongenomic estrogenic responses and could expand analysis along with other ERα mutant mice lacking membrane-bound ERα. We expect the H2NESKI mouse model to aid our understanding of ERα-mediated nongenomic physiological responses and serve as an in vivo model for evaluating the nongenomic action of various estrogenic agents.

2.
Int J Food Sci Technol ; 56(3): 1093-1114, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33776223

RESUMO

For many of the developing world's poorest farmers and food-insecure people, roots, tubers, bananas and plantain crops (RTBs) serve as a critical source of food, nutrition and cash income. RTBs have been particularly important in areas where local agri-food systems are under stress. Under such circumstances, growers, processors and traders often see opportunities to improve food security or increase their incomes with those crops due to shifting tastes and preferences for food and non-food products. Since the early 1990s, cassava output surged in sub-Saharan Africa, while potato production expanded rapidly in Asia. RTBs are consumed by over three billion people in developing countries with a market value of US$ 339 billion. This paper analyses the major changes in production, utilisation and trade of RTBs over the last six decades, assesses estimates of their future trajectory and offers recommendations so that they might achieve their full potential.

3.
J Vis Exp ; (135)2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29912196

RESUMO

In an effort to increase efficiency in the creation of genetically modified mice via ES Cell methodologies, we present an adaptation to the current blastocyst injection protocol. Here we report that a simple rotation of the embryo, and injection through Trans-Inner cell mass (TICM) increased the percentage of chimeric mice from 31% to 50%, with no additional equipment or further specialized training. 26 different inbred clones, and 35 total clones were injected over a period of 9 months. There was no significant difference in either pregnancy rate or recovery rate of embryos between traditional injection techniques and TICM. Therefore, without any major alteration in the injection process and a simple positioning of the blastocyst and injecting through the ICM, releasing the ES cells into the blastocoel cavity can potentially improve the quantity of chimeric production and subsequent germline transmission.


Assuntos
Quimerismo , Células-Tronco Embrionárias/metabolismo , Microinjeções/métodos , Animais , Feminino , Masculino , Camundongos , Gravidez
4.
Bone ; 88: 74-84, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27113526

RESUMO

Bone morphogenetic protein (BMP) signaling pathways play critical roles in skeletal development and new bone formation. Our previous study, however, showed a negative impact of BMP signaling on bone mass because of the osteoblast-specific loss of a BMP receptor (i.e. BMPR1A) showing increased trabecular bone volume and mineral density in mice. Here, we investigated the bone quality and biomechanical properties of the higher bone mass associated with BMPR1A deficiency using the osteoblast-specific Bmpr1a conditional knockout (cKO) mouse model. Collagen biochemical analysis revealed greater levels of the mature cross-link pyridinoline in the cKO bones, in parallel with upregulation of collagen modifying enzymes. Raman spectroscopy distinguished increases in the mature to immature cross-link ratio and mineral to matrix ratio in the trabecular compartments of cKO femora, but not in the cortical compartments. The mineral crystallinity was unchanged in the cKO in either the trabecular or cortical compartments. Further, we tested the intrinsic material properties by nanoindentation and found significantly higher hardness and elastic modulus in the cKO trabecular compartments, but not in the cortical compartments. Four point bending tests of cortical compartments showed lower structural biomechanical properties (i.e. strength and stiffness) in the cKO bones due to the smaller cortical areas. However, there were no significant differences in biomechanical performance at the material level, which was consistent with the nanoindentation test results on the cortical compartment. These studies emphasize the pivotal role of BMPR1A in the determination of bone quality and mechanical integrity under physiological conditions, with different impact on femoral cortical and trabecular compartments.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Osso Esponjoso/metabolismo , Colágeno/metabolismo , Reagentes de Ligações Cruzadas/metabolismo , Fêmur/metabolismo , Osteoblastos/metabolismo , Transdução de Sinais , Animais , Fenômenos Biomecânicos , Matriz Óssea/metabolismo , Osso Esponjoso/fisiologia , Módulo de Elasticidade , Fêmur/fisiologia , Regulação da Expressão Gênica , Dureza , Camundongos Transgênicos , Processamento de Proteína Pós-Traducional
5.
J Biol Chem ; 288(19): 13467-80, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23546880

RESUMO

BACKGROUND: The role of Smad-independent TGF-ß signaling in craniofacial development is poorly elucidated. RESULTS: In craniofacial mesenchymal cells, Tak1 regulates both R-Smad C-terminal and linker region phosphorylation in TGF-ß signaling. CONCLUSION: Tak1 plays an irreplaceable role in craniofacial ecto-mesenchyme during embryogenesis. SIGNIFICANCE: Understanding the mechanisms of TGF-ß signaling contributes to knowledge of pathogenetic mechanisms underlying common craniofacial birth defects. Although the importance of TGF-ß superfamily signaling in craniofacial growth and patterning is well established, the precise details of its signaling mechanisms are still poorly understood. This is in part because of the concentration of studies on the role of the Smad-dependent (so-called "canonical") signaling pathways relative to the Smad-independent ones in many biological processes. Here, we have addressed the role of TGF-ß-activated kinase 1 (Tak1, Map3k7), one of the key mediators of Smad-independent (noncanonical) TGF-ß superfamily signaling in craniofacial development, by deleting Tak1 specifically in the neural crest lineage. Tak1-deficient mutants display a round skull, hypoplastic maxilla and mandible, and cleft palate resulting from a failure of palatal shelves to appropriately elevate and fuse. Our studies show that in neural crest-derived craniofacial ecto-mesenchymal cells, Tak1 is not only required for TGF-ß- and bone morphogenetic protein-induced p38 Mapk activation but also plays a role in agonist-induced C-terminal and linker region phosphorylation of the receptor-mediated R-Smads. Specifically, we demonstrate that the agonist-induced linker region phosphorylation of Smad2 at Thr-220, which has been shown to be critical for full transcriptional activity of Smad2, is dependent on Tak1 activity and that in palatal mesenchymal cells TGFßRI and Tak1 kinases mediate both overlapping and distinct TGF-ß2-induced transcriptional responses. To summarize, our results suggest that in neural crest-derived ecto-mesenchymal cells, Tak1 provides a critical point of intersection in a complex dialogue between the canonical and noncanonical arms of TGF-ß superfamily signaling required for normal craniofacial development.


Assuntos
MAP Quinase Quinase Quinases/fisiologia , Crista Neural/citologia , Processamento de Proteína Pós-Traducional , Proteínas Smad/metabolismo , Motivos de Aminoácidos , Animais , Células Cultivadas , Fissura Palatina/enzimologia , Fissura Palatina/genética , Ectoderma/citologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Cabeça/embriologia , MAP Quinase Quinase Quinases/deficiência , MAP Quinase Quinase Quinases/genética , Masculino , Mandíbula/anormalidades , Camundongos , Camundongos Transgênicos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Proteínas Smad Reguladas por Receptor/metabolismo , Proteínas da Superfamília de TGF-beta/fisiologia , Proteína Wnt1/genética , Proteína Wnt1/metabolismo
6.
J Bone Miner Res ; 28(6): 1422-33, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23281127

RESUMO

Craniosynostosis describes conditions in which one or more sutures of the infant skull are prematurely fused, resulting in facial deformity and delayed brain development. Approximately 20% of human craniosynostoses are thought to result from gene mutations altering growth factor signaling; however, the molecular mechanisms by which these mutations cause craniosynostosis are incompletely characterized, and the causative genes for diverse types of syndromic craniosynostosis have yet to be identified. Here, we show that enhanced bone morphogenetic protein (BMP) signaling through the BMP type IA receptor (BMPR1A) in cranial neural crest cells, but not in osteoblasts, causes premature suture fusion in mice. In support of a requirement for precisely regulated BMP signaling, this defect was rescued on a Bmpr1a haploinsufficient background, with corresponding normalization of Smad phosphorylation. Moreover, in vivo treatment with LDN-193189, a selective chemical inhibitor of BMP type I receptor kinases, resulted in partial rescue of craniosynostosis. Enhanced signaling of the fibroblast growth factor (FGF) pathway, which has been implicated in craniosynostosis, was observed in both mutant and rescued mice, suggesting that augmentation of FGF signaling is not the sole cause of premature fusion found in this model. The finding that relatively modest augmentation of Smad-dependent BMP signaling leads to premature cranial suture fusion suggests an important contribution of dysregulated BMP signaling to syndromic craniosynostoses and potential strategies for early intervention.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Craniossinostoses/embriologia , Crista Neural/embriologia , Transdução de Sinais , Proteínas Smad/metabolismo , Animais , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/antagonistas & inibidores , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Proteínas Morfogenéticas Ósseas/genética , Craniossinostoses/genética , Craniossinostoses/metabolismo , Craniossinostoses/patologia , Humanos , Camundongos , Camundongos Transgênicos , Mutação , Crista Neural/metabolismo , Crista Neural/patologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Proteínas Smad/genética
7.
Genesis ; 47(6): 385-91, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19358156

RESUMO

BMPRIA and its high-affinity ligand BMP4 have recently been shown to be expressed in the beta-cells of the pancreas. Here, we report the abnormalities of heterozygous mice for Bmpr1a in glucose metabolism during the course of intraperitoneal glucose tolerance test. The heterozygous mice had increased blood glucose levels throughout the first 2.5 h after the administration of glucose. Analysis of glucose-stimulated insulin secretion (GSIS) indicates that insulin secretion in the heterozygous mice is compromised, and induction of secreted insulin by stimulation is substantially lower compared with the wild-type controls. No apparent abnormalities in pancreas, thyroid, and liver were seen upon histological examination. Real-time PCR results of selected genes showed an increase in the mRNA level of Ins1 and Ins2 in the heterozygous group. These results indicate that the glucose-sensing pathway in these heterozygous mice is altered because of the heterozygosity in Bmpr1a. Together, our data suggest that BMP signaling through BMPRIA plays an important role in glucose metabolism and possibly working through the GSIS pathway.


Assuntos
Glicemia/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Transdução de Sinais , Animais , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Feminino , Expressão Gênica , Glucose/metabolismo , Teste de Tolerância a Glucose/estatística & dados numéricos , Heterozigoto , Insulina/sangue , Insulina/genética , Insulina/metabolismo , Secreção de Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Mutantes , Proinsulina/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Arch. latinoam. nutr ; 43(2): 105-118, Jun. 1993.
Artigo em Espanhol | LILACS | ID: lil-319041

RESUMO

Post-harvest problems are important constraints to the expansion of production of food in many Latin American countries. Besides problems of bulkiness, perishability and seasonal production patterns, the necessity of reducing transportation costs, increasing rural employment, and finding new markets for processed products, requires the development of processing technologies. Possible processed products include a vast range of alternatives. Given limited time and resources, it is not always feasible to carry out detailed studies. Hence a practical, low-cost methodology is needed to evaluate the available options. This paper presents a series of methods to evaluate different processing possibilities. It describes in detail each method including a rapid initial assessment, market and consumer research, farm-oriented research, costs and returns analysis and finally, some marketing and promotion strategies.


Assuntos
Humanos , Manipulação de Alimentos/normas , Produtos Agrícolas/normas , Custos e Análise de Custo , Índia , América Latina , Manipulação de Alimentos/economia , Marketing de Serviços de Saúde , Produtos Agrícolas/economia , Comportamento do Consumidor
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