Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 76
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Mol Cell ; 83(5): 657-659, 2023 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-36868188

RESUMEN

Zhu and Hart1 use dual-specificity RNA aptamers to recruit cellular O-GlcNAc transferase (OGT) and induce O-GlcNAc on target proteins like ß-catenin, revealing that O-GlcNAc stabilizes ß-catenin and enhances its transcriptional activity.


Asunto(s)
Aptámeros de Nucleótidos , N-Acetilglucosaminiltransferasas , beta Catenina , N-Acetilglucosaminiltransferasas/química
2.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-34260378

RESUMEN

Centrosome duplication and DNA replication are two pivotal events that higher eukaryotic cells use to initiate proliferation. While DNA replication is initiated through origin licensing, centrosome duplication starts with cartwheel assembly and is partly controlled by CP110. However, the upstream coordinator for both events has been, until now, a mystery. Here, we report that suppressor of fused protein (Sufu), a negative regulator of the Hedgehog (Hh) pathway playing a significant role in restricting the trafficking and function of glioma-related (Gli) proteins, acts as an upstream switch by facilitating CP110 phosphorylation by CDK2, promoting intranuclear Cdt1 degradation and excluding prereplication complex (pre-RC) components from chromosomes, independent of its canonical function in the Hh pathway. We found that Sufu localizes to both the centrosome and the nucleus and that knockout of Sufu induces abnormalities including centrosome amplification, increased nuclear size, multipolar spindle formation, and polyploidy. Serum stimulation promotes the elimination of Sufu from the centrosome by vesicle release at the ciliary tip and from the nucleus via protein degradation, which allows centrosome duplication and DNA replication to proceed. Collectively, this work reveals a mechanism through which Sufu negatively regulates the G1-S transition.


Asunto(s)
Centrosoma/metabolismo , Replicación del ADN , Proteínas Represoras/metabolismo , Animales , Proteínas de Unión a Calmodulina/metabolismo , Proteínas de Ciclo Celular/metabolismo , Muerte Celular , Núcleo Celular/metabolismo , Cilios/metabolismo , Quinasa 2 Dependiente de la Ciclina/metabolismo , Vesículas Citoplasmáticas/metabolismo , Fibroblastos/metabolismo , Fase G1 , Células HEK293 , Células HeLa , Proteínas Hedgehog/metabolismo , Humanos , Ratones , Mitosis , Mutación/genética , Fosforilación , Proteolisis , Proteínas Represoras/genética , Fase S
3.
Biochem Cell Biol ; 101(4): 284-293, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-36821837

RESUMEN

Studies in the past decade have shown that lipid droplets stored in liver cells under starvation are encapsulated by autophagosomes and fused to lysosomes via the endocytic system. Autophagy responds to a variety of environmental factors inside and outside the cell, so it has a complex signal regulation network. To this end, we first explored the role of Hedgehog (Hh) in autophagy and lipid metabolism. Treatment of normal mouse liver cells with SAG and GDC-0449 revealed elevated phosphorylation of AMP-activated protein kinase (AMPK) and increased lipidation of LC3. SAG, and GDC-0449 were agonist and antagonist of Smoothened (Smo) in canonical Hh pathway, respectively, but they played a consistent role in the regulation of autophagy in hepatocytes. Moreover, SAG and GDC-0449 did not affect the expression of glioma-associated oncogene (Gli1) and patched 1, suggesting the absence of canonical Hh signaling in hepatocytes. We further knocked down the Smo and found that the effects of SAG and GDC-0449 disappeared, indicating that the non-canonical Smo pathway was involved in the regulation of autophagy in hepatocytes. In addition, SAG and GDC-0449 promoted lipid degradation and inhibited lipid production signals. Knockdown of Smo slowed down the rate of lipid degradation rather than Sufu or Gli1, indicating that Hh signaling regulated the lipid metabolism via Smo. In summary, activates AMPK via Smo to promote autophagy and lipid degradation.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Proteínas Hedgehog , Ratones , Animales , Proteínas Hedgehog/metabolismo , Proteína con Dedos de Zinc GLI1/genética , Hepatocitos/metabolismo , Autofagia , Lípidos , Receptores Acoplados a Proteínas G/metabolismo
4.
New Phytol ; 236(5): 1779-1795, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36093737

RESUMEN

The mediator complex is highly conserved in eukgaryotes and is integral for transcriptional responses. Mediator subunits associate with signal-responsive transcription factors (TF) to activate expression of specific signal-responsive genes. As the key TF of Arabidopsis thaliana senescence, ORESARA1 (ORE1) is required for nitrogen deficiency (-N) induced senescence; however, the mediator subunit that associates with ORE1 remains unknown. Here, we show that Arabidopsis MED19a associates with ORE1 to activate -N senescence-responsive genes. Disordered MED19a forms inducible nuclear condensates under -N that is regulated by decreasing MED19a lysine acetylation. MED19a carboxyl terminus (cMED19a) harbors a mixed-charged intrinsically disordered region (MC-IDR) required for ORE1 interaction and liquid-liquid phase separation (LLPS). Plant and human cMED19 are sufficient to form heterotypic condensates with ORE1. Human cMED19 MC-IDR, but not yeast cMED19 IDR, partially complements med19a suggesting functional conservation in evolutionarily distant eukaryotes. Phylogenetic analysis of eukaryotic cMED19 revealed that the MC-IDR could arise through convergent evolution. Our result of MED19 MC-IDR suggests that plant MED19 is regulated by phase separation during stress responses.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Complejo Mediador , Humanos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Complejo Mediador/genética , Complejo Mediador/metabolismo , Nutrientes , Filogenia , Transactivadores/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
5.
J Biol Chem ; 292(4): 1351-1360, 2017 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-27979967

RESUMEN

The function of the primary cilia, which is assembled in most vertebrate cells, is achieved by transport in and out of kinds of signaling receptors. The BBSome protein complex could recognize and target membrane proteins to the cilia, but how the BBSome itself is transported into the cilia is poorly understood. Here we demonstrate that the centrosome protein Dzip1 mediates the assembly of the BBSome-Dzip1-PCM1 complex in the centriolar satellites (CS) at the G0 phase for ciliary translocation of the BBSome. Phosphorylation of Dzip1 at Ser-210 by Plk1 (polo-like kinase 1) during the G2 phase promotes disassembly of this complex, resulting in removal of Dzip1 and the BBSome from the CS. Inhibiting the kinase activity of Plk1 maintains the CS localization of the BBSome and Dzip1 at the G2 phase. Collectively, our findings reveal the cell cycle-dependent regulation of BBSome transport to the CS and highlight a potential mechanism that the BBSome-mediated signaling pathways are accordingly regulated during the cell cycle.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas de Ciclo Celular/metabolismo , Centriolos/metabolismo , Proteínas de Unión al ADN/metabolismo , Fase G2/fisiología , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Proteínas de Ciclo Celular/genética , Centriolos/genética , Proteínas de Unión al ADN/genética , Células HEK293 , Humanos , Ratones , Células 3T3 NIH , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , Transporte de Proteínas/fisiología , Proteínas Proto-Oncogénicas/genética , Quinasa Tipo Polo 1
6.
Teach Learn Med ; 29(4): 402-410, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28498003

RESUMEN

Phenomenon: Professionalism is integral to the role of the physician. Most professionalism assessments in medical training are delayed until clinical rotations where multisource feedback is available. This leaves a gap in student assessment portfolios and potentially delays professional development. APPROACH: A total of 246 second-year medical students (2013-2015) completed self- and peer assessments of professional behaviors in 2 courses following a series of Team-Based Learning exercises. Correlation and regression analyses were used to examine the alignment or misalignment in the relationship between the 2 types of assessments. Four subgroups were formed based on observed patterns of initial self- and peer assessment alignment or misalignment, and subgroup membership stability over time was assessed. A missing data analysis examined differences between average peer assessment scores as a function of selective nonparticipation. FINDINGS: Spearman correlation demonstrated moderate to strong correlation between self-assessments completed alone (no simultaneous peer assessment) and self-assessments completed at the time of peer assessments (ρ = .59, p < .0001) but weak correlation between the two self-assessments and peer assessments (alone: ρ = .13, p < .013; at time of peer: ρ = .21, p < .0001). Generalized estimating equation models revealed that self-assessments done alone (p < .0001) were a significant predictor of self-assessments done at the time of peer. Course was also a significant predictor (p = .01) of self-assessment scores done at the time of peer. Peer assessment score was not a significant predictor. Bhapkar's test revealed subgroup membership based on the relationship between self- and peer ratings was relatively stable across Time 1 and Time 2 assessments (χ2 = 0.83, p = .84) for all but one subgroup; members of the subgroup with initially high self-assessment and low peer assessment were significantly more likely to move to a new classification at the second measurement. A missing data analysis revealed that students who completed all self-assessments had significantly higher average peer assessment ratings compared to students who completed one or no self-assessments with a difference of -0.32, 95% confidence interval [-0.48, -0.15]. Insights: Multiple measurements of simultaneous self- and peer assessment identified a subgroup of students who consistently rated themselves higher on professionalism attributes relative to the low ratings given by their peers. This subgroup of preclinical students, along with those who elected to not complete self-assessments, may be at risk for professionalism concerns. Use of this multisource feedback tool to measure perceptual stability of professionalism behaviors is a new approach that may assist with early identification of at-risk students during preclinical years.


Asunto(s)
Educación de Pregrado en Medicina/métodos , Retroalimentación Formativa , Grupo Paritario , Profesionalismo , Estudiantes de Medicina/estadística & datos numéricos , Adulto , Evaluación Educacional , Femenino , Humanos , Comunicación Interdisciplinaria , Masculino , Autoevaluación (Psicología) , Encuestas y Cuestionarios , Estados Unidos
7.
EMBO J ; 30(23): 4777-89, 2011 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-22045334

RESUMEN

TGF-ß signalling is regulated by post-translational modifications of Smad proteins to translate quantitative difference in ligand concentration into proportional transcriptional output. Previous studies in cell culture systems suggested that Smad ubiquitination regulatory factors (Smurfs) act in this regulation by targeting Smads for proteasomal degradation, but whether this mechanism operates under physiological conditions is not clear. Here, we generated mice harbouring a target-disrupted Smurf2 allele. Using primary mouse embryonic fibroblasts and dermal fibroblasts, we show that TGF-ß-mediated, Smad-dependent transcriptional responses are elevated in the absence of Smurf2. Instead of promoting poly-ubiquitination and degradation, we show that Smurf2 actually induces multiple mono-ubiquitination of Smad3 in vivo. Phosphorylation of T179, immediately upstream of the Smad3 PY motif, enhances Smurf2 and Smad3 interaction and Smad3 ubiquitination. We have mapped Smurf2-induced Smad3 ubiquitination sites to lysine residues at the MH2 domain, and demonstrate that Smad3 ubiquitination inhibits the formation of Smad3 complexes. Thus, our data support a model in which Smurf2 negatively regulates TGF-ß signalling by attenuating the activity of Smad3 rather than promoting its degradation.


Asunto(s)
Transducción de Señal/fisiología , Proteína smad3/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Ubiquitina-Proteína Ligasas , Ubiquitinación/fisiología , Animales , Western Blotting , Fibroblastos/metabolismo , Ratones , Modelos Biológicos , Unión Proteica , Transcripción Genética/fisiología , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
8.
Teach Learn Med ; 27(4): 362-5, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26507992

RESUMEN

UNLABELLED: CGEA 2015 CONFERENCE ABSTRACT (EDITED). A Novel Approach to Assessing Professionalism in Preclinical Medical Students Using Paired Self- and Peer Evaluations. Amanda R. Emke, Steven Cheng, and Carolyn Dufault. CONSTRUCT: This study sought to assess the professionalism of 2nd-year medical students in the context of team-based learning. BACKGROUND: Professionalism is an important attribute for physicians and a core competency throughout medical education. Preclinical training often focuses on individual knowledge acquisition with students working only indirectly with faculty assessors. As such, the assessment of professionalism in preclinical training continues to present challenges. We propose a novel approach to preclinical assessment of medical student professionalism to address these challenges. APPROACH: Second-year medical students completed self- and peer assessments of professionalism in two courses (Pediatrics and Renal/Genitourinary Diseases) following a series of team-based learning exercises. Assessments were composed of nearly identical 9-point rating scales. Correlational analysis and linear regression were used to examine the associations between self- and peer assessments and the effects of predictor variables. Four subgroups were formed based on deviation from the median ratings, and logistic regression was used to assess stability of subgroup membership over time. A missing data analysis was conducted to examine differences between average peer-assessment scores as a function of selective nonparticipation. RESULTS: There was a significant positive correlation (r = .62, p < .0001) between self-assessments completed alone and those completed at the time of peer assessment. There was also a significant positive correlation between average peer-assessment and self-assessment alone (r = .19, p < .0002) and self-assessment at the time of peer assessment (r = .27, p < .0001). Logistic regression revealed that subgroup membership was stable across measurement at two time points (T1 and T2) for all groups, except for members of the high self-assessment/low peer assessment at T1, who were significantly more likely to move to a new group at T2, χ(2)(3, N = 129) = 7.80, p < .05. Linear regression revealed that self-assessment alone and course were significant predictors of self-assessment at the time of peer assessment (Fself_alone = 144.74, p < .01 and Fcourse = 4.70, p < .05), whereas average peer rating, stage (T1, T2) and academic year (13-14, 14-15) were not. Linear regression also revealed that students who completed both self-assessments had significantly higher average peer assessment ratings (average peer rating in students with both self-assessments = 8.42, no self-assessments = 8.10, self_at_peer = 8.37, self_alone = 8.28) compared to students who completed one or no self-assessments (F = 5.34, p < .01). CONCLUSIONS: When used as a professionalism assessment within team-based learning, stand-alone and simultaneous peer and self-assessments are highly correlated within individuals across different courses. However, although self-assessment alone is a significant predictor of self-assessment made at the time of assessing one's peers, average peer assessment does not predict self-assessment. To explore this lack of predictive power, we classified students into four subgroups based on relative deviation from median peer and self-assessment scores. Group membership was found to be stable for all groups except for those initially sorted into the high self-assessment/low peer assessment subgroup. Members of this subgroup tended to move into the low self-assessment/low peer assessment group at T2, suggesting they became more accurate at self-assessing over time. A small group of individuals remained in the group that consistently rated themselves highly while their peers rated them poorly. Future studies will track these students to see if similar deviations from accurate professional self-assessment persist into the clinical years. In addition, given that students who fail to perform self-assessments had significantly lower peer assessment scores than their counterparts who completed self-assessments in this study, these students may also be at risk for similar professionalism concerns in the clinical years; follow-up studies will examine this possibility.


Asunto(s)
Educación de Pregrado en Medicina , Retroalimentación , Comunicación Interdisciplinaria , Aprendizaje , Profesionalismo , Humanos , Modelos Lineales , Grupo Paritario , Enseñanza/métodos
9.
Am J Nephrol ; 39(5): 392-9, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24818573

RESUMEN

BACKGROUND/AIMS: Progressive chronic kidney disease (CKD) is associated with worsening cardiovascular (CV) risk not explained by traditional risk factors. Left ventricular (LV) hypertrophy (LVH) is an important CV risk factor, but its progression has not been documented in early CKD. We explored whether progression of LVH in early CKD would occur despite stable kidney function. METHODS: We conducted a post hoc analysis of a 12-month study of lanthanum carbonate in stage 3 CKD, which included longitudinal assessments of CV biomarkers. Primary outcome for the analysis was the change in LV mass (LVM) indexed to height in meters(2.7) (LVM/Ht(2.7)). Secondary outcomes were changes in blood pressure (BP), pulse-wave velocity, LV systolic/diastolic function, fibroblast growth factor 23 (FGF23), klotho, and estimated glomerular filtration rate (eGFR). RESULTS: Thirty-one of 38 original subjects had sufficient data for analysis. LVM/Ht(2.7) increased (47 ± 13 vs. 53 ± 13 g/m(2.7), p = 0.006) over 12 months despite stable BP, stable eGFR and normal LV systolic function. Vascular stiffness and LV diastolic dysfunction persisted throughout the study. Klotho levels decreased (748 ± 289 to 536 ± 410 pg/ml, p = 0.03) but were unrelated to changes in LVM/Ht(2.7). The change in FGF23/klotho ratio was strongly correlated with changes in LVM/Ht(2.7) (r2 = 0.582, p = 0.03). CONCLUSION: Subjects with stage 3 CKD exhibited increasing LVM, persistent LV diastolic dysfunction and vascular stiffness despite stable kidney function, BP and LV systolic function. Abnormal FGF23 signaling due to reduced klotho expression may be associated with increasing LVM.


Asunto(s)
Ventrículos Cardíacos/patología , Hipertrofia Ventricular Izquierda/patología , Insuficiencia Renal Crónica/fisiopatología , Disfunción Ventricular Izquierda/fisiopatología , Anciano , Presión Sanguínea , Estatura , Progresión de la Enfermedad , Femenino , Factor-23 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos/sangre , Tasa de Filtración Glomerular , Glucuronidasa/sangre , Humanos , Hipertrofia Ventricular Izquierda/sangre , Hipertrofia Ventricular Izquierda/fisiopatología , Proteínas Klotho , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Análisis de la Onda del Pulso , Insuficiencia Renal Crónica/sangre , Rigidez Vascular
10.
Sheng Li Xue Bao ; 66(4): 415-22, 2014 Aug 25.
Artículo en Zh | MEDLINE | ID: mdl-25131782

RESUMEN

Hedgehog (Hh) signaling pathway plays an important role during embryonic development and pattern formation. Disruption of Hh pathway results in various developmental disorders and increasing cancer incidence. Here we provide a comprehensive review of the pathway members, focusing on how mammalian Hh regulates the Gli family of transcription factors through its downstream members, the so-called "canonical signaling pathway". Hh signaling pathway is highly conserved among species, and primary cilia plays an important role as a "signaling center" during vertebrate signal transduction. Further, in the past few years, numerous studies have shown that Hh signal can also be transduced through Gli-independent ways collectively referred to as "non-canonical signaling pathways", which can be subdivided into two modules: (i) those not requiring Smo and (ii) those downstream of Smo that do not require Gli transcription factors. Thus, we review the rapid progress on canonical and non-canonical Hh pathways.


Asunto(s)
Proteínas Hedgehog/fisiología , Transducción de Señal , Animales , Cilios/fisiología , Receptores Acoplados a Proteínas G/fisiología , Factores de Transcripción/fisiología
11.
JCI Insight ; 9(6)2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38358805

RESUMEN

Suppressor of fused (SUFU) is widely regarded as a key negative regulator of the sonic hedgehog (SHH) morphogenic pathway and a known tumor suppressor of medulloblastoma (MB). However, we report here that SUFU expression was markedly increased in 75% of specimens compiled in a tissue array comprising 49 unstratified MBs. The SUFU and GLI1 expression levels in this MB array showed strong positive correlation, which was also identified in a large public data set containing 736 MBs. We further report that increasing Sufu gene dosage in mice caused preaxial polydactyly, which was associated with the expansion of the Gli3 domain in the anterior limb bud and heightened Shh signaling responses during embryonic development. Increasing Sufu gene dosage also led to accelerated cerebellar development and, when combined with ablation of the Shh receptor encoded by Patched1 (Ptch1), promoted MB tumorigenesis. These data reveal multifaceted roles of SUFU in promoting MB tumorigenesis by enhancing SHH signaling. This revelation clarifies potentially counterintuitive clinical observation of high SUFU expression in MBs and may pave way for novel strategies to reduce or reverse MB progression.


Asunto(s)
Neoplasias Cerebelosas , Meduloblastoma , Polidactilia , Ratones , Animales , Meduloblastoma/genética , Meduloblastoma/patología , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Transformación Celular Neoplásica/genética , Factores de Transcripción , Neoplasias Cerebelosas/genética , Polidactilia/genética
12.
J Biol Chem ; 287(43): 36222-8, 2012 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-22930757

RESUMEN

Growth plate chondrocytes undergo a coordinated process of differentiation, regulating long bone growth. Parathyroid hormone-like hormone (Pthlh) inhibits hypertrophic differentiation in the growth plate chondrocytes and reduces Hedgehog (Hh) signaling. In mice lacking the Hh mediator Suppressor of fused (Sufu), Pthlh treatment resulted in the up-regulation of Hh activity and an increased number of hypertrophic chondrocytes. Furthermore, Pthlh increased Sufu protein levels, and in chondrocytes lacking Sufu, it was unable to process Hh-regulated Gli transcription factors. Pthlh regulates chondrocyte differentiation and Gli activity in a Sufu-dependent manner, with Sufu acting as a molecular switch in its regulation of differentiation.


Asunto(s)
Diferenciación Celular/fisiología , Condrocitos/metabolismo , Placa de Crecimiento/metabolismo , Proteína Relacionada con la Hormona Paratiroidea/metabolismo , Proteínas Represoras/metabolismo , Transducción de Señal/fisiología , Animales , Células Cultivadas , Condrocitos/citología , Placa de Crecimiento/citología , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Ratones , Ratones Mutantes , Proteína Relacionada con la Hormona Paratiroidea/genética , Proteínas Represoras/genética , Proteína con Dedos de Zinc GLI1
13.
Hum Mol Genet ; 20(19): 3725-37, 2011 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-21653639

RESUMEN

The primary cilium is emerging as a crucial regulator of signaling pathways central to vertebrate development and human disease. We identified atrioventricular canal 1 (avc1), a mouse mutation that caused VACTERL association with hydrocephalus, or VACTERL-H. We showed that avc1 is a hypomorphic mutation of intraflagellar transport protein 172 (Ift172), required for ciliogenesis and Hedgehog (Hh) signaling. Phenotypically, avc1 caused VACTERL-H but not abnormalities in left-right (L-R) axis formation. Avc1 resulted in structural cilia defects, including truncated cilia in vivo and in vitro. We observed a dose-dependent requirement for Ift172 in ciliogenesis using an allelic series generated with Ift172(avc1) and Ift172(wim), an Ift172 null allele: cilia were present on 42% of avc1 mouse embryonic fibroblast (MEF) and 28% of avc1/wim MEFs, in contrast to >90% of wild-type MEFs. Furthermore, quantitative cilium length analysis identified two specific cilium populations in mutant MEFS: a normal population with normal IFT and a truncated population, 50% of normal length, with disrupted IFT. Cells from wild-type embryos had predominantly full-length cilia, avc1 embryos, with Hh signaling abnormalities but not L-R abnormalities, had cilia equally divided between full-length and truncated, and avc1/wim embryos, with both Hh signaling and L-R abnormalities, were primarily truncated. Truncated Ift172 mutant cilia showed defects of the distal ciliary axoneme, including disrupted IFT88 localization and Hh-dependent Gli2 localization. We propose a model in which mutation of Ift172 results in a specific class of abnormal cilia, causing disrupted Hh signaling while maintaining L-R axis determination, and resulting in the VACTERL-H phenotype.


Asunto(s)
Cardiopatías Congénitas/genética , Hidrocefalia/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Deformidades Congénitas de las Extremidades/genética , Ratones/genética , Proteínas Adaptadoras Transductoras de Señales , Alelos , Canal Anal/anomalías , Canal Anal/embriología , Canal Anal/metabolismo , Animales , Cilios/genética , Cilios/metabolismo , Proteínas del Citoesqueleto , Modelos Animales de Enfermedad , Esófago/anomalías , Esófago/embriología , Esófago/metabolismo , Cardiopatías Congénitas/embriología , Cardiopatías Congénitas/metabolismo , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Humanos , Hidrocefalia/embriología , Hidrocefalia/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Riñón/anomalías , Riñón/embriología , Riñón/metabolismo , Deformidades Congénitas de las Extremidades/embriología , Deformidades Congénitas de las Extremidades/metabolismo , Ratones/metabolismo , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Mutagénesis , Mutación , Transporte de Proteínas , Transducción de Señal/genética , Columna Vertebral/anomalías , Columna Vertebral/embriología , Columna Vertebral/metabolismo , Tráquea/anomalías , Tráquea/embriología , Tráquea/metabolismo , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo
14.
Am J Nephrol ; 38(2): 158-67, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23941761

RESUMEN

BACKGROUND/AIMS: Cardiovascular disease (CVD) is increased in chronic kidney disease (CKD), and contributed to by the CKD-mineral bone disorder (CKD-MBD). CKD-MBD begins in early CKD and its vascular manifestations begin with vascular stiffness proceeding to increased carotid artery intima-media thickness (cIMT) and vascular calcification (VC). Phosphorus is associated with this progression and is considered a CVD risk factor in CKD. We hypothesized that modifying phosphorus balance with lanthanum carbonate (LaCO3) in early CKD would not produce hypophosphatemia and may affect vascular manifestations of CKD-MBD. METHODS: We randomized 38 subjects with normophosphatemic stage 3 CKD to a fixed dose of LaCO3 or matching placebo without adjusting dietary phosphorus in a 12-month randomized, double-blind, pilot and feasibility study. The primary outcome was the change in serum phosphorus. Secondary outcomes were changes in measures of phosphate homeostasis and vascular stiffness assessed by carotid-femoral pulse wave velocity (PWV), cIMT and VC over 12 months. RESULTS: There were no statistically significant differences between LaCO3 and placebo with respect to the change in serum phosphorus, urinary phosphorus, tubular reabsorption of phosphorus, PWV, cIMT, or VC. Biomarkers of the early CKD-MBD such as plasma fibroblast growth factor-23, Dickkopf-related protein 1 (DKK1), and sclerostin were increased 2- to 3-fold at baseline, but were not affected by LaCO3. CONCLUSION: Twelve months of LaCO3 had no effect on serum phosphorus and did not alter phosphate homeostasis, PWV, cIMT, VC, or biomarkers of CKD-MBD.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Insuficiencia Renal Crónica/tratamiento farmacológico , Rigidez Vascular , Anciano , Biomarcadores/metabolismo , Enfermedades Cardiovasculares/complicaciones , Complicaciones de la Diabetes/diagnóstico , Método Doble Ciego , Estudios de Factibilidad , Femenino , Homeostasis , Humanos , Lantano/uso terapéutico , Masculino , Persona de Mediana Edad , Fosfatos/química , Fósforo , Fósforo Dietético/metabolismo , Proyectos Piloto , Insuficiencia Renal Crónica/complicaciones , Factores de Riesgo , Resultado del Tratamiento
15.
J Gastrointest Oncol ; 14(2): 705-718, 2023 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-37201060

RESUMEN

Background: Colorectal cancer (CRC) is the third most common cancer worldwide and one of the leading causes of cancer-related death. Peptidomics, considered a novel branch of proteomics, has an increasing range of applications in the screening, diagnosis, prognosis, and even monitoring of cancer. However, there is little information for peptidomics analysis in CRC. Methods: In this study, a comparative peptidomic profiling was analyzed in 3 CRC tissue samples and 3 adjacent intestinal epithelial tissue samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results: Among the total 133 nonredundant peptides identified, 59 were significantly differentially expressed in the CRC samples and benign colonic epithelium conditions [fold change (FC) >2, P<0.05]. Totals of 25 up-regulated and 34 down-regulated peptides were detected, respectively. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were applied to predict the possible functions of these relevant precursor proteins. To clearly identify the potential interaction network of peptide precursors, the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) was used to determine protein interactions and a possible central role in CRC. Conclusions: Our results for the first time revealed the differentially expressed peptides between the serous CRC tissue and the adjacent intestinal epithelial tissue samples, and these prominently variable peptides might have an important potential role in occurrence and development of CRC.

16.
Nat Plants ; 9(10): 1598-1606, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37735255

RESUMEN

Nitrogen is an essential macronutrient that is absorbed by roots and stored in leaves, mainly as ribulose-1,5-bisphosphate carboxylase/oxygenase1,2. During nitrogen deficiency (-N), plants activate leaf senescence for source-to-sink nitrogen remobilization for adaptative growth3-6. However, how -N signals perceived by roots are propagated to shoots remains underexplored. We found that ELF18-INDUCED LONG NONCODING RNA 1 (ELENA1) is -N inducible and attenuates -N-induced leaf senescence in Arabidopsis. Analysis of plants expressing the ELENA1 promoter ß-glucuronidase fusion gene showed that ELENA1 is transcribed specifically in roots under -N. Reciprocal grafting of the wild type and elena1 demonstrated that ELENA1 functions systemically. ELENA1 dissociates the MEDIATOR SUBUNIT 19a-ORESARA1 transcriptional complex, thereby calibrating senescence progression. Our observations establish the systemic regulation of leaf senescence by a root-derived long non-coding RNA under -N in Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , ARN Largo no Codificante , Nitrógeno/metabolismo , Arabidopsis/metabolismo , ARN Largo no Codificante/genética , Senescencia de la Planta , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Hojas de la Planta/metabolismo , Regulación de la Expresión Génica de las Plantas
17.
Cell Biosci ; 13(1): 15, 2023 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-36683064

RESUMEN

BACKGROUND: Medulloblastoma (MB) is one of the most common malignant pediatric brain tumors. Metastasis and relapse are the leading causes of death in MB patients. The initiation of the SHH subgroup of MB (SHH-MB) is due to the aberrant activation of Sonic Hedgehog (Shh) signaling. However, the mechanisms for its metastasis are still unknown. RESULTS: AMP-dependent protein kinase (AMPK) restrains the activation of Shh signaling pathway, thereby impeding the proliferation of SHH-MB cells. More importantly, AMPK also hinders the growth and metastasis of SHH-MB cells by regulating NF-κB signaling pathway. Furthermore, Vismodegib and TPCA-1, which block the Shh and NF-κB pathways, respectively, synergistically restrained the growth, migration, and invasion of SHH-MB cells. CONCLUSIONS: This work demonstrates that AMPK functions through two signaling pathways, SHH-GLI1 and NF-κB. AMPK-NF-κB axis is a potential target for molecular therapy of SHH-MB, and the combinational blockade of NF-κB and Shh pathways confers synergy for SHH-MB therapy.

18.
J Biol Chem ; 286(15): 13502-11, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21317289

RESUMEN

Suppressor of fused (Sufu) is an essential negative regulator of the sonic hedgehog (Shh) pathway, but little is known about how Sufu itself is normally regulated. Here, we report that Sufu is phosphorylated at Ser-342 and Ser-346 by GSK3ß and cAMP-dependent protein kinase A (PKA), respectively, and phosphorylation at this dual site stabilizes Sufu against Shh signaling-induced degradation. We further show that localization of Sufu in the primary cilium is induced by Shh signaling and is required for the turnover of both phosphorylated and total Sufu. Perturbing Sufu phosphorylation with PKA inhibitors or replacing Ser-346 with alanine reduced the stay and replacing Ser-342 and Ser-346 with aspartic acid prolonged the stay of Sufu in the cilia. Finally, ciliary localization of Gli2/3 also required Smo and was similarly influenced by perturbations of PKA activity or mutations at the dual Sufu phosphorylation site. Thus, Shh likely induced trafficking of phospho-Sufu into the primary cilium in a complex with Gli2/3, and dephosphorylation triggered a retrograde export, allowing Sufu to be degraded by the ubiquitin-proteasome system.


Asunto(s)
Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Glucógeno Sintasa Quinasa 3/metabolismo , Proteínas Represoras/metabolismo , Sustitución de Aminoácidos , Animales , Cilios/genética , Cilios/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/genética , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3 beta , Células HEK293 , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Humanos , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Ratones , Mutación Missense , Células 3T3 NIH , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosforilación/fisiología , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Estabilidad Proteica , Transporte de Proteínas/fisiología , Proteínas Represoras/genética , Ubiquitina/genética , Ubiquitina/metabolismo , Proteína Gli2 con Dedos de Zinc , Proteína Gli3 con Dedos de Zinc
19.
ACS Appl Mater Interfaces ; 14(28): 32579-32589, 2022 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-35794731

RESUMEN

Facemasks as personal protective equipment play a significant role in helping prevent the spread of viruses during the COVID-19 pandemic. A desired reusable fabric facemask should strike a balance of water repellency, good filtration efficiency (FE), breathability, and mechanical robustness against washing cycles. Despite significant efforts in testing various commercial fabric materials for filtration efficiency, few have investigated fabric performance as a function of the fiber/yarn morphology and wettability of the fabric itself. In this study, we examine commercial fabrics with Janus-like behaviors to determine the best reusable fabric facemask materials by understanding the roles of morphology, porosity, and wettability of the fabric on its overall performance. We find that the outer layer of the diaper fabric consisted of laminated polyurethane, which is hydrophobic, has low porosity (∼5%) and tightly woven yarn structures, and shows the highest overall FE (up to 54%) in the submicron particle size range (0.03-0.6 µm) among the fabrics tested. Fabric layers with higher porosity lead to lower-pressure drops, indicating higher breathability but lower FE. Tightly woven waterproof rainwear fabrics perform the best after 10 washing cycles, remaining intact morphologically with only a 2-5% drop in the overall FE in the submicron particle size range, whereas other knitted fabric layers become loosened and the laminated polyurethane thin film on the diaper fabric is wrinkled. In comparison, the surgical masks and N95 respirators made from nonwoven polypropylene (PP) fibers see over a 30% decline in the overall FE after 10 washing cycles. Overall, we find that tightly woven Janus fabrics consisting of a low porosity, a hydrophobic outer layer, and a high porosity and hydrophilic inner layer offer the best performance among the fabrics tested as they can generate a high overall FE, achieve good breathability, and maintain fabric morphology and performance over multiple washing cycles.

20.
Lung Cancer ; 166: 197-204, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35313244

RESUMEN

OBJECTIVES: The MYLUNG (Molecularly Informed Lung Cancer Treatment in a Community Cancer Network) consortium pragmatic study assessed real-world biomarker testing rates and turnaround times within a large community-based oncology network. MATERIALS AND METHODS: This retrospective observational chart review study investigated patients with mNSCLC initiating first-line (1L) systemic therapy between 01-April-2018 and 31-March-2020. Biomarker testing rates and timing relative to 1L therapy for EGFR, ALK, ROS1, BRAF, and PD-L1 were assessed, including use of next-generation sequencing (NGS). RESULTS: Among 3474 adults: 74% had adenocarcinoma and 76% had a documented ECOG performance status of 0 or 1. Ninety percent had testing for at least one biomarker, and 46% received all 5 biomarker tests. Changes in testing rates from 2018 to 2020 were 71% to 71% for EGFR, 71% to 70% for ALK, 69% to 67% for ROS1, 51% to 59% for BRAF, 82% to 84% for PD-L1, and 42% to 49% for all 5 biomarkers. NGS testing increased from 33% to 45% (p < 0.0001). Median time from mNSCLC diagnosis to 1L therapy was 35 days. Median turnaround times from biomarker testing orders to results ranged from 10 to 15 days for the individual biomarkers and 18 days for NGS. CONCLUSION: In this real-world study, while most patients received at least one biomarker test prior to 1L, <50% received all 5 tests. NGS testing also occurred in < 50% of patients but appeared to increase over time. The next phase of MYLUNG will evaluate contemporary ordering practices and turnaround times prospectively.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Adulto , Antígeno B7-H1 , Biomarcadores , Biomarcadores de Tumor , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Mutación , Proteínas Tirosina Quinasas/genética , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Tirosina Quinasas Receptoras , Estudios Retrospectivos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA