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3.
Front Psychol ; 15: 1366617, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39015333

RESUMEN

The nature and origins of addictions and of their adjunctive behaviors, as well as their chronicity, call for treatments that conceptualize and treat them as the long-term and complex processes that they are. Addictions are often comorbid with personality problems and with trauma histories. Patients suffering from these disorders often show poor engagement with treatment and high rates of relapse, possibly because available treatments have yet to address the patient suffering from addiction in a more integrated or holistic manner. In particular, comprehensive treatment models for addictive disorders - like treatments for personality disorders or trauma - are likely to require the integration of behavioral, cognitive, and emotion-focused interventions within a facilitative therapeutic relationship. However, most current treatment models, including ones which are highly effective in stabilization or behavioral change, lack one or more components of treatment that could sustain longer term recovery, wellness, and health for a higher percentage of patients. In this article, I propose approaching addictions and their treatment from the perspective of schema therapy, an integrative, developmental model with a strong track record of positive outcomes in addressing personality disorder symptoms and long-standing trauma histories, commonly comorbid with addictive disorders. In advancing this proposal, I begin by providing some background tying together addictions, attachment, and personality, suggesting they be treated simultaneously to achieve improved outcomes. Then, after briefly reviewing the leading approaches to the treatment of addictions, I introduce the idea that schema therapy is well-situated - both theoretically and practically - to address many of the shortcomings of existing treatment options. In particular, I note how addictive and co-occurring colluding behaviors are deeply intertwined with both early and continued frustration of core developmental needs. I illustrate how the addictive cycle is perpetuated through the process of schema reinforcement and through the operation of schema modes. I then demonstrate how these key terms (i.e., needs, schemas, and modes) inform the patient's assessment and case formulation, guiding treatment interventions from a strong therapeutic relationship that focuses on integrating recovery behavior change, healing dysfunctional schemas and modes, and preventing relapse.

4.
Am Surg ; 90(8): 2124-2126, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38578102

RESUMEN

Tension pneumothorax (TPT) identified in the prehospital setting requires prehospital needle decompression (PHND). This study aimed to evaluate complications from PHND when it was performed without meeting clinical criteria. A retrospective review was performed of patients undergoing (PHND) from 2016 through 2022 at a level 1 trauma center. Patient data who received PHND were reviewed. Of 115 patients, 85 did not meet at least one clinical criterion for PHND. The majority of patients in this cohort 76 (89%) required a chest tube and 22 (25%) had an iatrogenic pneumothorax from PHND. 5 patients (6%) were admitted due to iatrogenic PHND. Two vascular injuries in this population were directly due to PHND and required emergency operative repair. This study shows the negative consequences of PHND when performed without clear indications. Several patients underwent unnecessary procedures with significant clinical consequences.


Asunto(s)
Descompresión Quirúrgica , Servicios Médicos de Urgencia , Agujas , Neumotórax , Humanos , Neumotórax/cirugía , Neumotórax/etiología , Estudios Retrospectivos , Masculino , Femenino , Descompresión Quirúrgica/métodos , Adulto , Persona de Mediana Edad , Enfermedad Iatrogénica , Anciano , Resultado del Tratamiento
5.
Biol Open ; 11(8)2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-35876795

RESUMEN

Formation of a properly sized and patterned embryo during gastrulation requires a well-coordinated interplay between cell proliferation, lineage specification and tissue morphogenesis. Following transient physical or pharmacological manipulations of embryo size, pre-gastrulation mouse embryos show remarkable plasticity to recover and resume normal development. However, it remains unclear how mechanisms driving lineage specification and morphogenesis respond to defects in cell proliferation during and after gastrulation. Null mutations in DNA replication or cell-cycle-related genes frequently lead to cell-cycle arrest and reduced cell proliferation, resulting in developmental arrest before the onset of gastrulation; such early lethality precludes studies aiming to determine the impact of cell proliferation on lineage specification and morphogenesis during gastrulation. From an unbiased ENU mutagenesis screen, we discovered a mouse mutant, tiny siren (tyrn), that carries a hypomorphic mutation producing an aspartate to tyrosine (D939Y) substitution in Pold1, the catalytic subunit of DNA polymerase δ. Impaired cell proliferation in the tyrn mutant leaves anterior-posterior patterning unperturbed during gastrulation but results in reduced embryo size and severe morphogenetic defects. Our analyses show that the successful execution of morphogenetic events during gastrulation requires that lineage specification and the ordered production of differentiated cell types occur in concordance with embryonic growth.


Asunto(s)
ADN Polimerasa III , Gastrulación , Animales , ADN Polimerasa III/genética , Embrión de Mamíferos , Gastrulación/genética , Ratones , Morfogénesis/genética , Mutación
6.
Dev Biol ; 341(1): 154-66, 2010 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-20178780

RESUMEN

During vesicular transport between the endoplasmic reticulum and the Golgi, members of the TMED/p24 protein family form hetero-oligomeric complexes that facilitate protein-cargo recognition as well as vesicle budding. In addition, they regulate each other's level of expression. Despite analyses of TMED/p24 protein distribution in mammalian cells, yeast, and C. elegans, little is known about the role of this family in vertebrate embryogenesis. We report the presence of a single point mutation in Tmed2/p24beta(1) in a mutant mouse line, 99J, identified in an ENU mutagenesis screen for recessive developmental abnormalities. This mutation does not affect Tmed2/p24beta(1) mRNA levels but results in loss of TMED2/p24beta(1) protein. Prior to death at mid-gestation, 99J homozygous mutant embryos exhibit developmental delay, abnormal rostral-caudal elongation, randomized heart looping, and absence of the labyrinth layer of the placenta. We find that Tmed2/p24beta(1) is normally expressed in tissues showing morphological defects in 99J mutant embryos and that these affected tissues lack the TMED2/p24beta(1) oligomerization partners, TMED7/p24gamma(3) and TMED10/p24delta(1). Our data reveal a requirement for TMED2/p24beta(1) protein in the morphogenesis of the mouse embryo and placenta.


Asunto(s)
Embrión de Mamíferos/metabolismo , Morfogénesis , Placenta/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Animales , Retículo Endoplásmico/metabolismo , Femenino , Regulación del Desarrollo de la Expresión Génica , Proteínas de la Membrana , Ratones , Ratones Endogámicos C57BL , Mutación , Embarazo
7.
DNA Repair (Amst) ; 108: 103227, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34601382

RESUMEN

RAD51 paralogs are key components of the homologous recombination (HR) machinery. Mouse mutants have been reported for four of the canonical RAD51 paralogs, and each of these mutants exhibits embryonic lethality, although at different gestational stages. However, the phenotype of mice deficient in the fifth RAD51 paralog, XRCC3, has not been reported. Here we report that Xrcc3 knockout mice exhibit midgestational lethality, with mild phenotypes beginning at about E8.25 but severe developmental abnormalities evident by E9.0-9.5. The most obvious phenotypes are small size and a failure of the embryo to turn to a fetal position. A knockin mutation at a key ATPase residue in the Walker A box results in embryonic lethality at a similar stage. Death of knockout mice can be delayed a few days for some embryos by homozygous or heterozygous Trp53 mutation, in keeping with an important role for XRCC3 in promoting genome integrity. Given that XRCC3 is a unique member of one of two RAD51 paralog complexes with RAD51C, these results demonstrate that both RAD51 paralog complexes are required for mouse development.


Asunto(s)
Proteínas de Unión al ADN , Recombinación Homóloga , Recombinasa Rad51 , Adenosina Trifosfatasas/genética , Animales , Proteínas de Unión al ADN/genética , Femenino , Ratones , Embarazo , Recombinasa Rad51/genética
8.
Cell Rep ; 23(8): 2443-2454, 2018 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-29791854

RESUMEN

Nup133 belongs to the Y-complex, a key component of the nuclear pore complex (NPC) scaffold. Studies on a null mutation in mice previously revealed that Nup133 is essential for embryonic development but not for mouse embryonic stem cell (mESC) proliferation. Using single-pore detection and average NE-fluorescence intensity, we find that Nup133 is dispensable for interphase and postmitotic NPC scaffold assembly in pluripotent mESCs. However, loss of Nup133 specifically perturbs the formation of the nuclear basket as manifested by the absence of Tpr in about half of the NPCs combined with altered dynamics of Nup153. We further demonstrate that its central domain mediates Nup133's role in assembling Tpr and Nup153 into a properly configured nuclear basket. Our findings thus revisit the role of the Y-complex in pore biogenesis and provide insights into the interplay between NPC scaffold architecture, nuclear basket assembly, and the generation of heterogeneity among NPCs.


Asunto(s)
Antígenos de Histocompatibilidad Menor/metabolismo , Células Madre Embrionarias de Ratones/metabolismo , Proteínas de Complejo Poro Nuclear/metabolismo , Poro Nuclear/metabolismo , Animales , Femenino , Imagenología Tridimensional , Interfase , Masculino , Ratones , Antígenos de Histocompatibilidad Menor/química , Proteínas de Complejo Poro Nuclear/química , Dominios Proteicos , Proteínas Proto-Oncogénicas/metabolismo
9.
Arterioscler Thromb Vasc Biol ; 26(9): 2103-9, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16825592

RESUMEN

OBJECTIVE: Angiogenic expansion of the vasa vasorum is a well-known feature of progressive atherosclerosis, suggesting that antiangiogenic therapies may stabilize or regress plaques. Alpha(v)beta3 integrin-targeted paramagnetic nanoparticles were prepared for noninvasive assessment of angiogenesis in early atherosclerosis, for site-specific delivery of antiangiogenic drug, and for quantitative follow-up of response. METHODS AND RESULTS: Expression of alpha(v)beta3 integrin by vasa vasorum was imaged at 1.5 T in cholesterol-fed rabbit aortas using integrin-targeted paramagnetic nanoparticles that incorporated fumagillin at 0 microg/kg or 30 microg/kg. Both formulations produced similar MRI signal enhancement (16.7%+/-1.1%) when integrated across all aortic slices from the renal arteries to the diaphragm. Seven days after this single treatment, integrin-targeted paramagnetic nanoparticles were readministered and showed decreased MRI enhancement among fumagillin-treated rabbits (2.9%+/-1.6%) but not in untreated rabbits (18.1%+/-2.1%). In a third group of rabbits, nontargeted fumagillin nanoparticles did not alter vascular alpha(v)beta3-integrin expression (12.4%+/-0.9%; P>0.05) versus the no-drug control. In a second study focused on microscopic changes, fewer microvessels in the fumagillin-treated rabbit aorta were counted compared with control rabbits. CONCLUSIONS: This study illustrates the potential of combined molecular imaging and drug delivery with targeted nanoparticles to noninvasively define atherosclerotic burden, to deliver effective targeted drug at a fraction of previous levels, and to quantify local response to treatment.


Asunto(s)
Inhibidores de la Angiogénesis/administración & dosificación , Aterosclerosis/metabolismo , Sistemas de Liberación de Medicamentos , Endotelio Vascular/metabolismo , Ácidos Grasos Insaturados/administración & dosificación , Integrina alfaVbeta3/metabolismo , Nanoestructuras , Neovascularización Patológica/prevención & control , Inhibidores de la Angiogénesis/farmacología , Animales , Aorta Abdominal/patología , Aterosclerosis/complicaciones , Aterosclerosis/diagnóstico , Ciclohexanos , Ácidos Grasos Insaturados/farmacología , Hiperlipidemias/sangre , Imagen por Resonancia Magnética , Neovascularización Patológica/etiología , Conejos , Sesquiterpenos
10.
Artículo en Inglés | MEDLINE | ID: mdl-16964911

RESUMEN

We describe characterization of backscatter from tumor tissue targeted with a nanoparticle-based ultrasound contrast agent in vivo using analogs of thermodynamic quantities. We apply these waveform characteristics to detection of tumor neovasculature in tumors implanted in athymic nude mice, which were imaged using a research ultrasound scanner over a 2-hour period after injection of alpha upsilon beta3-targeted perfluorocarbon nanoparticles. Images were constructed from backscattered ultrasound using two different approaches: fundamental B-mode imaging and a signal receiver based on a thermodynamic analog (H(C)). The study shows that the thermodynamic analog is capable of detecting differences in backscattered signals that are not apparent with the B-mode approach.


Asunto(s)
Algoritmos , Neoplasias de la Mama/diagnóstico por imagen , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Procesamiento de Señales Asistido por Computador , Ultrasonografía/métodos , Animales , Línea Celular Tumoral , Medios de Contraste , Sistemas de Liberación de Medicamentos/métodos , Humanos , Ratones , Ratones Desnudos , Termodinámica
11.
Lab Anim (NY) ; 35(10): 27-34, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17077832

RESUMEN

The times they are a-changin' for GEM and the facilities that maintain them. Core facilities are expanding beyond their original conception as producers of transgenic mice to encompass a wide range of services, including research animal maintenance. In this paper, the authors describe the logistics and administration of the newly dubbed Mouse Genetics Core Facility at the Memorial Sloan-Kettering Cancer Center as a blueprint for other institutions seeking to expand and update their own transgenic cores for research in the twenty-first century.


Asunto(s)
Crianza de Animales Domésticos/organización & administración , Investigación Biomédica/organización & administración , Ciencia de los Animales de Laboratorio/organización & administración , Ciencia de los Animales de Laboratorio/tendencias , Ratones Transgénicos , Crianza de Animales Domésticos/métodos , Crianza de Animales Domésticos/tendencias , Animales , Investigación Biomédica/métodos , Investigación Biomédica/tendencias , Ratones , New York , Registros , Técnicas de Cultivo de Tejidos
12.
Cancer Res ; 63(18): 5838-43, 2003 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-14522907

RESUMEN

Early noninvasive detection and characterization of solid tumors and their supporting neovasculature is a fundamental prerequisite for effective therapeutic intervention, particularly antiangiogenic treatment regimens. Emerging molecular imaging techniques now allow recognition of early biochemical, physiological, and anatomical changes before manifestation of gross pathological changes. Although new tumor, vascular, extracellular matrix, and lymphatic biomarkers continue to be discovered, the alpha(nu)beta(3)-integrin remains an attractive biochemical epitope that is highly expressed on activated neovascular endothelial cells and essentially absent on mature quiescent cells. In this study, we report the first in vivo use of a magnetic resonance (MR) molecular imaging nanoparticle to sensitively detect and spatially characterize neovascularity induced by implantation of the rabbit Vx-2 tumor using a common clinical field strength (1.5T). New Zealand White rabbits (2 kg) 12 days after implantation of fresh Vx-2 tumors (2 x 2 x 2 mm(3)) were randomized into one of three treatment groups: (a) alpha(nu)beta(3)-targeted, paramagnetic formulation; (b) nontargeted, paramagnetic formulation; and (c) alpha(nu)beta(3)-targeted nonparamagnetic nanoparticles followed by (2 h) the alpha(nu)beta(3)-targeted, paramagnetic formulation to competitively block magnetic resonance imaging (MRI) signal enhancement. After i.v. systemic injection (0.5 ml of nanoparticles/kg), dynamic T(1)-weighted MRI was used to spatially and temporally determine nanoparticle deposition in the tumor and adjacent tissues, including skeletal muscle. At 2-h postinjection, alpha(nu)beta(3)-targeted paramagnetic nanoparticles increased MRI signal by 126% in asymmetrically distributed regions primarily in the periphery of the tumor. Similar increases in MR contrast were also observed within the walls of some vessels proximate to the tumor. Despite their relatively large size, nanoparticles penetrated into the leaky tumor neovasculature but did not appreciably migrate into the interstitium, leading to a 56% increase in MR signal at 2 h. Pretargeting of the alpha(nu)beta(3)-integrin with nonparamagnetic nanoparticles competitively blocked the specific binding of alpha(nu)beta(3)-targeted paramagnetic nanoparticles, decreasing the MR signal enhancement (50%) to a level attributable to local extravasation. The MR signal of adjacent hindlimb muscle or contralateral control tissues was unchanged by either the alpha(nu)beta(3)-targeted or control paramagnetic agents. Immunohistochemistry of alpha(nu)beta(3)-integrin corroborated the extent and asymmetric distribution of neovascularity observed by MRI. These studies demonstrate the potential of this targeted molecular imaging agent to detect and characterize (both biochemically and morphologically) early angiogenesis induced by minute solid tumors with a clinical 1.5 Tesla MRI scanner, facilitating the localization of nascent cancers or metastases, as well as providing tools to phenotypically categorize and segment patient populations for therapy and to longitudinally follow the effectiveness of antitumor treatment regimens.


Asunto(s)
Integrina alfaVbeta3/metabolismo , Angiografía por Resonancia Magnética/métodos , Neoplasias Experimentales/irrigación sanguínea , Neovascularización Patológica/metabolismo , Animales , Miembro Posterior , Integrina alfaVbeta3/biosíntesis , Masculino , Nanotecnología , Trasplante de Neoplasias , Neovascularización Patológica/diagnóstico , Tamaño de la Partícula , Conejos
13.
Dev Cell ; 37(6): 488-90, 2016 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-27326926

RESUMEN

The signaling pathways and cellular mechanisms that achieve alignment of dorsal and ventral midline structures remain a poorly understood aspect of vertebrate development. In this issue of Developmental Cell, Arraf et al. (2016) find a requisite role for bilaterally symmetrical BMP signaling in coordinating dorsal and ventral tissue morphogenesis.


Asunto(s)
Proteínas Morfogenéticas Óseas/metabolismo , Crecimiento y Desarrollo , Animales , Embrión de Pollo , Pollos , Modelos Biológicos , Morfogénesis , Transducción de Señal
14.
Circulation ; 108(18): 2270-4, 2003 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-14557370

RESUMEN

BACKGROUND: Angiogenesis is a critical feature of plaque development in atherosclerosis and might play a key role in both the initiation and later rupture of plaques that lead to myocardial infarction and stroke. The precursory molecular or cellular events that initiate plaque growth and that ultimately contribute to plaque instability, however, cannot be detected directly with any current diagnostic modality. METHODS AND RESULTS: Atherosclerosis was induced in New Zealand White rabbits fed 1% cholesterol for approximately 80 days. alpha(v)beta3-Integrin-targeted, paramagnetic nanoparticles were injected intravenously and provided specific detection of the neovasculature within 2 hours by routine magnetic resonance imaging (MRI) at a clinically relevant field strength (1.5 T). Increased angiogenesis was detected as a 47+/-5% enhancement in MRI signal averaged throughout the abdominal aortic wall among rabbits that received alpha(v)beta3-targeted, paramagnetic nanoparticles. Pretreatment of atherosclerotic rabbits with alpha(v)beta3-targeted, nonparamagnetic nanoparticles competitively blocked specific contrast enhancement of the alpha(v)beta3-targeted paramagnetic agent. MRI revealed a pattern of increased alpha(v)beta3-integrin distribution within the atherosclerotic wall that was spatially heterogeneous along both transverse and longitudinal planes of the abdominal aorta. Histology and immunohistochemistry confirmed marked proliferation of angiogenic vessels within the aortic adventitia, coincident with prominent, neointimal proliferation among cholesterol-fed, atherosclerotic rabbits in comparison with sparse incidence of neovasculature in the control animals. CONCLUSIONS: This molecular imaging approach might provide a method for defining the burden and evolution of atherosclerosis in susceptible individuals as well as responsiveness of individual patients to antiatherosclerotic therapies.


Asunto(s)
Arteriosclerosis/metabolismo , Arteriosclerosis/patología , Integrina alfaVbeta3/metabolismo , Neovascularización Patológica/patología , Animales , Aorta/patología , Arteriosclerosis/inducido químicamente , Colesterol en la Dieta , Medios de Contraste/administración & dosificación , Modelos Animales de Enfermedad , Inmunohistoquímica , Integrina alfaVbeta3/análisis , Imagen por Resonancia Magnética , Masculino , Tamaño de la Partícula , Conejos , Sensibilidad y Especificidad
15.
Cell Rep ; 9(2): 674-87, 2014 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-25373905

RESUMEN

Sorting and degradation of receptors and associated signaling molecules maintain homeostasis of conserved signaling pathways during cell specification and tissue development. Yet, whether machineries that sort signaling proteins act preferentially on different receptors and ligands in different contexts remains mysterious. Here, we show that Vacuolar protein sorting 25, Vps25, a component of ESCRT-II (Endosomal Sorting Complex Required for Transport II), directs preferential endosome-mediated modulation of FGF signaling in limbs. By ENU-induced mutagenesis, we isolated a polydactylous mouse line carrying a hypomorphic mutation of Vps25 (Vps25(ENU)). Unlike Vps25-null embryos we generated, Vps25(ENU/ENU) mutants survive until late gestation. Their limbs display FGF signaling enhancement and consequent hyperactivation of the FGF-SHH feedback loop causing polydactyly, whereas WNT and BMP signaling remain unperturbed. Notably, Vps25(ENU/ENU) Mouse Embryonic Fibroblasts exhibit aberrant FGFR trafficking and degradation; however, SHH signaling is unperturbed. These studies establish that the ESCRT-II machinery selectively limits FGF signaling in vertebrate skeletal patterning.


Asunto(s)
Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , Endosomas/metabolismo , Factores de Crecimiento de Fibroblastos/metabolismo , Proteínas Hedgehog/metabolismo , Polidactilia/genética , Transducción de Señal , Proteínas de Transporte Vesicular/genética , Animales , Complejos de Clasificación Endosomal Requeridos para el Transporte/genética , Extremidades/crecimiento & desarrollo , Retroalimentación Fisiológica , Fibroblastos/metabolismo , Ratones , Ratones Endogámicos C57BL , Mutación , Polidactilia/metabolismo , Proteínas de Transporte Vesicular/metabolismo
16.
Curr Opin Genet Dev ; 23(4): 461-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23706163

RESUMEN

Ventral folding morphogenesis (VFM), a vital morphogenetic process in amniotes, mediates gut endoderm internalization, linear heart tube formation, ventral body wall closure and encasement of the fetus in extraembryonic membranes. Aberrant VFM underlies a number of birth defects such as gastroschisis and ectopia cordis in human and misplacement of head and heart in mouse. Recent cell lineage-specific mouse mutant analyses identified the Bone Morphogenetic Protein (BMP) pathway and Anterior Visceral Endoderm (AVE) as key regulators of anterior VFM. Loss of BMP2 expression solely from embryonic visceral endoderm (EmVE) and the AVE blocks formation of foregut invagination, and simultaneously, aberrantly positions the heart anterior/dorsal to the head, suggesting a mechanistic link between foregut and head/heart morphogenesis.


Asunto(s)
Tipificación del Cuerpo/genética , Proteína Morfogenética Ósea 2/genética , Endodermo/crecimiento & desarrollo , Morfogénesis/genética , Animales , Proteína Morfogenética Ósea 2/metabolismo , Linaje de la Célula , Desarrollo Embrionario , Endodermo/metabolismo , Regulación del Desarrollo de la Expresión Génica , Cabeza/crecimiento & desarrollo , Corazón/crecimiento & desarrollo , Humanos , Ratones
18.
Cell Res ; 22(8): 1258-69, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22453236

RESUMEN

Mutations of the CUL4B ubiquitin ligase gene are causally linked to syndromic X-linked mental retardation (XLMR). However, the pathogenic role of CUL4B mutations in neuronal and developmental defects is not understood. We have generated mice with targeted disruption of Cul4b, and observed embryonic lethality with pronounced growth inhibition and increased apoptosis in extra-embryonic tissues. Cul4b, but not its paralog Cul4a, is expressed at high levels in extra-embryonic tissues post implantation. Silencing of CUL4B expression in an extra-embryonic cell line resulted in the robust accumulation of the CUL4 substrate p21(Cip1/WAF) and G2/M cell cycle arrest, which could be partially rescued by silencing of p21(Cip1/WAF). Epiblast-specific deletion of Cul4b prevented embryonic lethality and gave rise to viable Cul4b null mice. Therefore, while dispensable in the embryo proper, Cul4b performs an essential developmental role in the extra-embryonic tissues. Our study offers a strategy to generate viable Cul4b-deficient mice to model the potential neuronal and behavioral deficiencies of human CUL4B XLMR patients.


Asunto(s)
Proteínas Cullin/metabolismo , Embrión de Mamíferos/patología , Desarrollo Embrionario , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Alelos , Animales , Apoptosis , Cruzamientos Genéticos , Proteínas Cullin/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Pérdida del Embrión/enzimología , Pérdida del Embrión/genética , Embrión de Mamíferos/metabolismo , Femenino , Puntos de Control de la Fase G2 del Ciclo Celular , Silenciador del Gen , Genotipo , Estratos Germinativos/citología , Estratos Germinativos/metabolismo , Patrón de Herencia , Puntos de Control de la Fase M del Ciclo Celular , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación , Embarazo , Inactivación del Cromosoma X
19.
Dev Cell ; 21(5): 907-19, 2011 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-22075149

RESUMEN

In amniotes, ventral folding morphogenesis achieves gut internalization, linear heart tube formation, ventral body wall closure, and encasement of the fetus in extraembryonic membranes. Impairment of ventral morphogenesis results in human birth defects involving body wall, gut, and heart malformations and in mouse misplacement of head and heart. Absence of knowledge about genetic pathways and cell populations directing ventral folding in mammals has precluded systematic study of cellular mechanisms driving this vital morphogenetic process. We report tissue-specific mouse mutant analyses identifying the bone morphogenetic protein (BMP) pathway as a key regulator of ventral morphogenesis. BMP2 expressed in anterior visceral endoderm (AVE) signals to epiblast derivatives during gastrulation to orchestrate initial stages of ventral morphogenesis, including foregut development and positioning of head and heart. These findings identify unanticipated functions for the AVE in organizing the gastrulating embryo and indicate that visceral endoderm-expressed BMP2 coordinates morphogenetic cell behaviors in multiple epiblast lineages.


Asunto(s)
Proteína Morfogenética Ósea 2/metabolismo , Endodermo/metabolismo , Cabeza/embriología , Corazón/embriología , Morfogénesis , Animales , Proteína Morfogenética Ósea 2/deficiencia , Proteína Morfogenética Ósea 2/genética , Embrión de Mamíferos/citología , Embrión de Mamíferos/metabolismo , Endodermo/citología , Hibridación in Situ , Ratones , Ratones Noqueados
20.
Dev Cell ; 14(6): 831-42, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18539113

RESUMEN

Serving as the primary conduit for communication between the nucleus and the cytoplasm, nuclear pore complexes (NPCs) impact nearly every cellular process. The extent to which NPC composition varies and the functional significance of such variation in mammalian development has not been investigated. Here we report that a null allele of mouse nucleoporin Nup133, a structural subunit of the NPC, disrupts neural differentiation. We find that expression of Nup133 is cell type and developmental stage restricted, with prominent expression in dividing progenitors. Nup133-deficient epiblast and ES cells abnormally maintain features of pluripotency and differentiate inefficiently along the neural lineage. Neural progenitors achieve correct spatial patterning in mutant embryos; however, they are impaired in generating terminally differentiated neurons, as are Nup133 null ES cells. Our results reveal a role for structural nucleoporins in coordinating cell differentiation events in the developing embryo.


Asunto(s)
Diferenciación Celular , Neuronas/fisiología , Poro Nuclear/química , Células Madre/fisiología , Alelos , Animales , Biomarcadores/metabolismo , Diferenciación Celular/genética , Linaje de la Célula/genética , Células Cultivadas , Mapeo Cromosómico , Cruzamientos Genéticos , Embrión de Mamíferos , Gástrula , Regulación del Desarrollo de la Expresión Génica , Hibridación in Situ , Ratones , Ratones Congénicos , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Antígenos de Histocompatibilidad Menor , Mutación , Proteínas de Complejo Poro Nuclear/química , Proteínas de Complejo Poro Nuclear/genética , Proteínas de Complejo Poro Nuclear/metabolismo , Transcripción Genética
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