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1.
Cell ; 184(4): 899-911.e13, 2021 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-33545089

RESUMEN

Changes in appendage structure underlie key transitions in vertebrate evolution. Addition of skeletal elements along the proximal-distal axis facilitated critical transformations, including the fin-to-limb transition that permitted generation of diverse modes of locomotion. Here, we identify zebrafish mutants that form supernumerary long bones in their pectoral fins. These new bones integrate into musculature, form joints, and articulate with neighboring elements. This phenotype is caused by activating mutations in previously unrecognized regulators of appendage patterning, vav2 and waslb, that function in a common pathway. This pathway is required for appendage development across vertebrates, and loss of Wasl in mice causes defects similar to those seen in murine Hox mutants. Concordantly, formation of supernumerary bones requires Hox11 function, and mutations in the vav2/wasl pathway drive enhanced expression of hoxa11b, indicating developmental homology with the forearm. Our findings reveal a latent, limb-like pattern ability in fins that is activated by simple genetic perturbation.


Asunto(s)
Huesos/embriología , Extremidades/embriología , Pez Cebra/embriología , Actinas/metabolismo , Aletas de Animales/embriología , Animales , Secuencia de Bases , Tipificación del Cuerpo , Sistemas CRISPR-Cas/genética , Linaje de la Célula , Epistasis Genética , Regulación del Desarrollo de la Expresión Génica , Técnicas de Inactivación de Genes , Genes Reporteros , Células HeLa , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Ratones , Mutación/genética , Fenotipo , Filogenia , Transducción de Señal/genética , Pez Cebra/genética , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo
2.
Development ; 151(7)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38602508

RESUMEN

The skull roof, or calvaria, is comprised of interlocking plates of bones that encase the brain. Separating these bones are fibrous sutures that permit growth. Currently, we do not understand the instructions for directional growth of the calvaria, a process which is error-prone and can lead to skeletal deficiencies or premature suture fusion (craniosynostosis, CS). Here, we identify graded expression of fibronectin (FN1) in the mouse embryonic cranial mesenchyme (CM) that precedes the apical expansion of calvaria. Conditional deletion of Fn1 or Wasl leads to diminished frontal bone expansion by altering cell shape and focal actin enrichment, respectively, suggesting defective migration of calvarial progenitors. Interestingly, Fn1 mutants have premature fusion of coronal sutures. Consistently, syndromic forms of CS in humans exhibit dysregulated FN1 expression, and we also find FN1 expression altered in a mouse CS model of Apert syndrome. These data support a model of FN1 as a directional substrate for calvarial osteoblast migration that may be a common mechanism underlying many cranial disorders of disparate genetic etiologies.


Asunto(s)
Fibronectinas , Nacimiento Prematuro , Cráneo , Animales , Femenino , Humanos , Ratones , Señales (Psicología) , Modelos Animales de Enfermedad , Fibronectinas/metabolismo , Osteoblastos , Cráneo/citología , Cráneo/crecimiento & desarrollo , Cráneo/metabolismo , Suturas
3.
Nature ; 587(7835): 650-656, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33149304

RESUMEN

G-protein-coupled receptors (GPCRs) are membrane proteins that modulate physiology across human tissues in response to extracellular signals. GPCR-mediated signalling can differ because of changes in the sequence1,2 or expression3 of the receptors, leading to signalling bias when comparing diverse physiological systems4. An underexplored source of such bias is the generation of functionally diverse GPCR isoforms with different patterns of expression across different tissues. Here we integrate data from human tissue-level transcriptomes, GPCR sequences and structures, proteomics, single-cell transcriptomics, population-wide genetic association studies and pharmacological experiments. We show how a single GPCR gene can diversify into several isoforms with distinct signalling properties, and how unique isoform combinations expressed in different tissues can generate distinct signalling states. Depending on their structural changes and expression patterns, some of the detected isoforms may influence cellular responses to drugs and represent new targets for developing drugs with improved tissue selectivity. Our findings highlight the need to move from a canonical to a context-specific view of GPCR signalling that considers how combinatorial expression of isoforms in a particular cell type, tissue or organism collectively influences receptor signalling and drug responses.


Asunto(s)
Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal/efectos de los fármacos , Transcriptoma , Bases de Datos Factuales , Perfilación de la Expresión Génica , Células HEK293 , Humanos , Terapia Molecular Dirigida , Especificidad de Órganos/efectos de los fármacos , Isoformas de Proteínas/genética , Proteómica , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Receptores Acoplados a Proteínas G/genética , Transducción de Señal/genética , Análisis de la Célula Individual
4.
Diabetologia ; 67(3): 528-546, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38127123

RESUMEN

AIMS/HYPOTHESIS: Diabetes mellitus is associated with impaired insulin secretion, often aggravated by oversecretion of glucagon. Therapeutic interventions should ideally correct both defects. Glucagon-like peptide 1 (GLP-1) has this capability but exactly how it exerts its glucagonostatic effect remains obscure. Following its release GLP-1 is rapidly degraded from GLP-1(7-36) to GLP-1(9-36). We hypothesised that the metabolite GLP-1(9-36) (previously believed to be biologically inactive) exerts a direct inhibitory effect on glucagon secretion and that this mechanism becomes impaired in diabetes. METHODS: We used a combination of glucagon secretion measurements in mouse and human islets (including islets from donors with type 2 diabetes), total internal reflection fluorescence microscopy imaging of secretory granule dynamics, recordings of cytoplasmic Ca2+ and measurements of protein kinase A activity, immunocytochemistry, in vivo physiology and GTP-binding protein dissociation studies to explore how GLP-1 exerts its inhibitory effect on glucagon secretion and the role of the metabolite GLP-1(9-36). RESULTS: GLP-1(7-36) inhibited glucagon secretion in isolated islets with an IC50 of 2.5 pmol/l. The effect was particularly strong at low glucose concentrations. The degradation product GLP-1(9-36) shared this capacity. GLP-1(9-36) retained its glucagonostatic effects after genetic/pharmacological inactivation of the GLP-1 receptor. GLP-1(9-36) also potently inhibited glucagon secretion evoked by ß-adrenergic stimulation, amino acids and membrane depolarisation. In islet alpha cells, GLP-1(9-36) led to inhibition of Ca2+ entry via voltage-gated Ca2+ channels sensitive to ω-agatoxin, with consequential pertussis-toxin-sensitive depletion of the docked pool of secretory granules, effects that were prevented by the glucagon receptor antagonists REMD2.59 and L-168049. The capacity of GLP-1(9-36) to inhibit glucagon secretion and reduce the number of docked granules was lost in alpha cells from human donors with type 2 diabetes. In vivo, high exogenous concentrations of GLP-1(9-36) (>100 pmol/l) resulted in a small (30%) lowering of circulating glucagon during insulin-induced hypoglycaemia. This effect was abolished by REMD2.59, which promptly increased circulating glucagon by >225% (adjusted for the change in plasma glucose) without affecting pancreatic glucagon content. CONCLUSIONS/INTERPRETATION: We conclude that the GLP-1 metabolite GLP-1(9-36) is a systemic inhibitor of glucagon secretion. We propose that the increase in circulating glucagon observed following genetic/pharmacological inactivation of glucagon signalling in mice and in people with type 2 diabetes reflects the removal of GLP-1(9-36)'s glucagonostatic action.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hipoglucemia , Islotes Pancreáticos , Fragmentos de Péptidos , Humanos , Glucagón/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Péptido 1 Similar al Glucagón/metabolismo , Islotes Pancreáticos/metabolismo , Hipoglucemia/metabolismo , Insulina/metabolismo
5.
Proteins ; 92(5): 649-664, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38149328

RESUMEN

Glial fibrillary acidic protein (GFAP) is a promising biomarker for brain and spinal cord disorders. Recent studies have highlighted the differences in the reliability of GFAP measurements in different biological matrices. The reason for these discrepancies is poorly understood as our knowledge of the protein's 3-dimensional conformation, proteoforms, and aggregation remains limited. Here, we investigate the structural properties of GFAP under different conditions. For this, we characterized recombinant GFAP proteins from various suppliers and applied hydrogen-deuterium exchange mass spectrometry (HDX-MS) to provide a snapshot of the conformational dynamics of GFAP in artificial cerebrospinal fluid (aCSF) compared to the phosphate buffer. Our findings indicate that recombinant GFAP exists in various conformational species. Furthermore, we show that GFAP dimers remained intact under denaturing conditions. HDX-MS experiments show an overall decrease in H-bonding and an increase in solvent accessibility of GFAP in aCSF compared to the phosphate buffer, with clear indications of mixed EX2 and EX1 kinetics. To understand possible structural interface regions and the evolutionary conservation profiles, we combined HDX-MS results with the predicted GFAP-dimer structure by AlphaFold-Multimer. We found that deprotected regions with high structural flexibility in aCSF overlap with predicted conserved dimeric 1B and 2B domain interfaces. Structural property predictions combined with the HDX data show an overall deprotection and signatures of aggregation in aCSF. We anticipate that the outcomes of this research will contribute to a deeper understanding of the structural flexibility of GFAP and ultimately shed light on its behavior in different biological matrices.


Asunto(s)
Medición de Intercambio de Deuterio , Proteína Ácida Fibrilar de la Glía , Fosfatos , Humanos , Medición de Intercambio de Deuterio/métodos , Proteína Ácida Fibrilar de la Glía/química , Proteína Ácida Fibrilar de la Glía/genética , Proteína Ácida Fibrilar de la Glía/fisiología , Conformación Proteica , Reproducibilidad de los Resultados , Proteínas Recombinantes
6.
J Mol Evol ; 92(2): 93-103, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38416218

RESUMEN

Ecological and evolutionary transitions offer an excellent opportunity to examine the molecular basis of adaptation. Fishes of the order Beloniformes include needlefishes, flyingfishes, halfbeaks, and allies, and comprise over 200 species occupying a wide array of habitats-from the marine epipelagic zone to tropical rainforest rivers. These fishes also exhibit a diversity of diets, including piscivory, herbivory, and zooplanktivory. We investigated how diet and habitat affected the molecular evolution of cone opsins, which play a key role in bright light and colour vision and are tightly linked to ecology and life history. We analyzed a targeted-capture dataset to reconstruct the evolutionary history of beloniforms and assemble cone opsin sequences. We implemented codon-based clade models of evolution to examine how molecular evolution was affected by habitat and diet. We found high levels of positive selection in medium- and long-wavelength beloniform opsins, with piscivores showing increased positive selection in medium-wavelength opsins and zooplanktivores showing increased positive selection in long-wavelength opsins. In contrast, short-wavelength opsins showed purifying selection. While marine/freshwater habitat transitions have an effect on opsin molecular evolution, we found that diet plays a more important role. Our study suggests that evolutionary transitions along ecological axes produce complex adaptive interactions that affect patterns of selection on genes that underlie vision.


Asunto(s)
Opsinas de los Conos , Animales , Opsinas de los Conos/genética , Filogenia , Opsinas/genética , Peces/genética , Evolución Molecular
7.
Development ; 148(10)2021 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-33999994

RESUMEN

It is well known that electrical signals are deeply associated with living entities. Much of our understanding of excitable tissues is derived from studies of specialized cells of neurons or myocytes. However, electric potential is present in all cell types and results from the differential partitioning of ions across membranes. This electrical potential correlates with cell behavior and tissue organization. In recent years, there has been exciting, and broadly unexpected, evidence linking the regulation of development to bioelectric signals. However, experimental modulation of electrical potential can have multifaceted and pleiotropic effects, which makes dissecting the role of electrical signals in development difficult. Here, I review evidence that bioelectric cues play defined instructional roles in orchestrating development and regeneration, and further outline key areas in which to refine our understanding of this signaling mechanism.


Asunto(s)
Comunicación Celular/fisiología , Fenómenos Electrofisiológicos/fisiología , Desarrollo Embrionario/fisiología , Potenciales de la Membrana/fisiología , Regeneración/fisiología , Animales , Transporte Biológico/fisiología , Tipificación del Cuerpo/fisiología , Humanos , Canales Iónicos/fisiología , Transducción de Señal/fisiología
8.
J Neurol Neurosurg Psychiatry ; 95(8): 748-752, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38199813

RESUMEN

BACKGROUND: Consistent patterns of reduced cortical thickness have been identified in early Alzheimer's disease (AD). However, the pathological factors that influence rates of cortical thinning within these AD signature regions remain unclear. METHODS: Participants were from the Insight 46 substudy of the MRC National Survey of Health and Development (NSHD; 1946 British birth cohort), a prospective longitudinal cohort study. Linear regression was used to examine associations of baseline cerebral ß-amyloid (Aß) deposition, measured using florbetapir positron emission tomography, and baseline white matter hyperintensity volume (WMHV) on MRI, a marker of cerebral small vessel disease, with subsequent longitudinal changes in AD signature cortical thickness quantified from baseline and repeat MRI (mean [SD] interval 2.4 [0.2] years). RESULTS: In a population-based sample of 337 cognitively normal older white adults (mean [SD] age at baseline 70.5 [0.6] years; 48.1% female), higher global WMHV at baseline related to faster subsequent rates of cortical thinning in both AD signature regions (~0.15%/year faster per 10 mL additional WMHV), whereas baseline Aß status did not. Among Aß positive participants (n=56), there was some evidence that greater global Aß standardised uptake value ratio at baseline related to faster cortical thinning in the AD signature Mayo region, but this did not reach statistical significance (p=0.08). CONCLUSIONS: Cortical thinning within AD signature regions may develop via cerebrovascular pathways. Perhaps reflecting the age of the cohort and relatively low prevalence of Aß-positivity, robust Aß-related differences were not detected. Longitudinal follow-up incorporating additional biomarkers will allow assessment of how these relationships evolve closer to expected dementia onset.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Adelgazamiento de la Corteza Cerebral , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Sustancia Blanca , Humanos , Femenino , Masculino , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Estudios Longitudinales , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Adelgazamiento de la Corteza Cerebral/diagnóstico por imagen , Adelgazamiento de la Corteza Cerebral/patología , Estudios Prospectivos , Glicoles de Etileno , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Corteza Cerebral/metabolismo , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Enfermedades de los Pequeños Vasos Cerebrales/patología , Compuestos de Anilina
9.
Am J Med Genet A ; 194(8): e63615, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38563316

RESUMEN

The Society for Craniofacial Genetics and Developmental Biology (SCGDB) held its 46th Annual Meeting at Cincinnati Children's Hospital Medical Center in Cincinnati, Ohio on October 10th-12th, 2023. On the first day of the meeting, Drs. Sally Moody and Justin Cotney were each honored with the SCGDB Distinguished Scientist Awards for their exceptional contributions to the field of craniofacial biology. The following two days of the meeting featured five sessions that highlighted new discoveries in signaling and genomic mechanisms regulating craniofacial development, human genetics, translational and regenerative approaches, and clinical management of craniofacial differences. Interactive workshops on spatial transcriptomics and scientific communication, as well as a poster session facilitated meaningful interactions among the 122 attendees representing diverse career stages and research backgrounds in developmental biology and genetics, strengthened the SCGDB community.


Asunto(s)
Anomalías Craneofaciales , Biología Evolutiva , Humanos , Anomalías Craneofaciales/genética , Anomalías Craneofaciales/patología
10.
Surg Endosc ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886232

RESUMEN

BACKGROUND: There is little international data on morbidity and mortality of surgery for perforated peptic ulcer (PPU). This study aimed to understand the global 30-day morbidity and mortality of patients undergoing surgery for PPU and to identify variables associated with these. METHOD: We performed an international study of adults (≥ 18 years) who underwent surgery for PPU from 1st January 2022 to 30th June 2022. Patients who were treated conservatively or had an underlying gastric cancer were excluded. Patients were divided into subgroups according to age (≤ 50 and > 50 years) and time from onset of symptoms to hospital presentation (≤ 24 and > 24 h). Univariate and Multivariate analyses were carried out to identify factors associated with higher 30-day morbidity and mortality. RESULTS:  1874 patients from 159 centres across 52 countries were included. 78.3% (n = 1467) of the patients were males and the median (IQR) age was 49 years (25). Thirty-day morbidity and mortality were 48.5% (n = 910) and 9.3% (n = 174) respectively. Median (IQR) hospital stay was 7 (5) days. Open surgery was performed in 80% (n = 1505) of the cohort. Age > 50 years [(OR = 1.7, 95% CI 1.4-2), (OR = 4.7, 95% CI 3.1-7.6)], female gender [(OR = 1.8, 95% CI 1.4-2.3), (OR = 1.9, 95% CI 1.3-2.9)], shock on admission [(OR = 2.1, 95% CI 1.7-2.7), (OR = 4.8, 95% CI 3.2-7.1)], and acute kidney injury [(OR = 2.5, 95% CI 1.9-3.2), (OR = 3.9), 95% CI 2.7-5.6)] were associated with both 30-day morbidity and mortality. Delayed presentation was associated with 30-day morbidity [OR = 1.3, 95% CI 1.1-1.6], but not mortality. CONCLUSIONS: This study showed that surgery for PPU was associated with high 30-day morbidity and mortality rate. Age, female gender, and signs of shock at presentation were associated with both 30-day morbidity and mortality.

11.
Anaesthesia ; 79(8): 856-868, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38699880

RESUMEN

BACKGROUND: There are concerns that airway management in patients with suspected or confirmed cervical spine injury may exacerbate an existing neurological deficit, cause a new spinal cord injury or be hazardous due to precautions to avoid neurological injury. However, there are no evidence-based guidelines for practicing clinicians to support safe and effective airway management in this setting. METHODS: An expert multidisciplinary, multi-society working party conducted a systematic review of contemporary literature (January 2012-June 2022), followed by a three-round Delphi process to produce guidelines to improve airway management for patients with suspected or confirmed cervical spine injury. RESULTS: We included 67 articles in the systematic review, and successfully agreed 23 recommendations. Evidence supporting recommendations was generally modest, and only one moderate and two strong recommendations were made. Overall, recommendations highlight key principles and techniques for pre-oxygenation and facemask ventilation; supraglottic airway device use; tracheal intubation; adjuncts during tracheal intubation; cricoid force and external laryngeal manipulation; emergency front-of-neck airway access; awake tracheal intubation; and cervical spine immobilisation. We also signpost to recommendations on pre-hospital care, military settings and principles in human factors. CONCLUSIONS: It is hoped that the pragmatic approach to airway management made within these guidelines will improve the safety and efficacy of airway management in adult patients with suspected or confirmed cervical spine injury.


Asunto(s)
Manejo de la Vía Aérea , Vértebras Cervicales , Servicios Médicos de Urgencia , Traumatismos Vertebrales , Humanos , Manejo de la Vía Aérea/métodos , Manejo de la Vía Aérea/normas , Vértebras Cervicales/lesiones , Traumatismos Vertebrales/terapia , Servicios Médicos de Urgencia/métodos , Servicios Médicos de Urgencia/normas , Sociedades Médicas , Intubación Intratraqueal/métodos , Técnica Delphi
12.
Proc Natl Acad Sci U S A ; 118(11)2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-33688049

RESUMEN

A liquid-liquid transition (LLT) is a transformation from one liquid to another through a first-order transition. The LLT is fundamental to the understanding of the liquid state and has been reported in a few materials such as silicon, phosphorus, triphenyl phosphite, and water. Furthermore, it has been suggested that the unique properties of materials such as water, which is critical for life on the planet, are linked to the existence of the LLT. However, the experimental evidence for the existence of an LLT in many molecular liquids remains controversial, due to the prevalence and high propensity of the materials to crystallize. Here, we show evidence of an LLT in a glass-forming trihexyltetradecylphosphonium borohydride ionic liquid that shows no tendency to crystallize under normal laboratory conditions. We observe a step-like increase in the static dielectric permittivity at the transition. Furthermore, the sizes of nonpolar local domains and ion-coordination numbers deduced from wide-angle X-ray scattering also change abruptly at the LLT. We independently corroborate these changes in local organization using Raman spectroscopy. The experimental access to the evolution of local order and structural dynamics across a liquid-liquid transition opens up unprecedented possibilities to understand the nature of the liquid state.

13.
Cardiol Young ; 34(2): 387-394, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37462049

RESUMEN

BACKGROUND: Patients with unbalanced common atrioventricular canal can be difficult to manage. Surgical planning often depends on pre-operative echocardiographic measurements. We aimed to determine the added utility of cardiac MRI in predicting successful biventricular repair in common atrioventricular canal. METHODS: We conducted a retrospective cohort study of children with common atrioventricular canal who underwent MRI prior to repair. Associations between MRI and echocardiographic measures and surgical outcome were tested using logistic regression, and models were compared using area under the receiver operator characteristic curve. RESULTS: We included 28 patients (median age at MRI: 5.2 months). The optimal MRI model included the novel end-diastolic volume index (using the ratio of left ventricular end-diastolic volume to total end-diastolic volume) and the left ventricle-right ventricle angle in diastole (area under the curve 0.83, p = 0.041). End-diastolic volume index ≤ 0.18 and left ventricle-right ventricle angle in diastole ≤ 72° yield a sensitivity of 83% and specificity of 81% for successful biventricular repair. The optimal multimodality model included the end-diastolic volume index and the echocardiographic atrioventricular valve index with an area under the curve of 0.87 (p = 0.026). CONCLUSIONS: Cardiac MRI can successfully predict successful biventricular repair in patients with unbalanced common atrioventricular canal utilising the end-diastolic volume index alone or in combination with the MRI left ventricle-right ventricle angle in diastole or the echocardiographic atrioventricular valve index. A prospective cardiac MRI study is warranted to better define the multimodality characteristic predictive of successful biventricular surgery.


Asunto(s)
Defectos de los Tabiques Cardíacos , Niño , Humanos , Lactante , Estudios Retrospectivos , Defectos de los Tabiques Cardíacos/cirugía , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/cirugía , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética
14.
J Am Chem Soc ; 145(47): 25518-25522, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37963184

RESUMEN

High impact recent articles have reported on the existence of a liquid-liquid (L-L) phase transition as a function of both pressure and temperature in ionic liquids (ILs) containing the popular trihexyltetradecylphosphonium cation (P666,14+), sometimes referred to as the "universal liquifier". The work presented here reports on the structural-dynamic pathway from liquid to glass of the most well-studied IL comprising the P666,14+ cation. We present experimental and computational evidence that, on cooling, the path from the room-temperature liquid to the glass state is one of separate structural-dynamic changes. The first stage involves the slowdown of the charge network, while the apolar subcomponent is fully mobile. A second, separate stage entails the slowdown of the apolar domain. Whereas it is possible that these processes may be related to the liquid-liquid and glass transitions, more research is needed to establish this conclusively.

15.
Am J Transplant ; 23(2): 165-170, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36695696

RESUMEN

For decades, transplantation has been a life-saving treatment for those fortunate enough to gain access. Nevertheless, many patients die waiting for an organ and countless more never make it onto the waitlist because of a shortage of donor organs. Concurrently, thousands of donated organs are declined for transplant each year because of concerns about poor outcomes post-transplant. The decline of any donated organ-even if medically justified-is tragic for both the donor family and potential recipients. In this Personal Viewpoint, we discuss the need for a new mindset in how we honor the gift of organ donation. We believe that the use of transplant-declined human organs in translational research has the potential to hasten breakthrough discoveries in a multitude of scientific and medical areas. More importantly, such breakthroughs will allow us to properly value every donated organ. We further discuss the many practical challenges that such research presents and offer some possible solutions based on experiences in our own research laboratories. Finally, we share our perspective on what we believe are the necessary next steps to ensure a future where every donated organ realizes its full potential to impact the lives of current and future patients.


Asunto(s)
Trasplante de Órganos , Obtención de Tejidos y Órganos , Humanos , Donantes de Tejidos , Listas de Espera
16.
Development ; 147(2)2020 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-31932352

RESUMEN

Evolution is replete with reuse of genes in different contexts, leading to multifunctional roles of signaling factors during development. Here, we explore osteoclast regulation during skeletal development through analysis of colony-stimulating factor 1 receptor (csf1r) function in the zebrafish. A primary role of Csf1r signaling is to regulate the proliferation, differentiation and function of myelomonocytic cells, including osteoclasts. We demonstrate the retention of two functional paralogues of csf1r in zebrafish. Mutant analysis indicates that the paralogues have shared, non-redundant roles in regulating osteoclast activity during the formation of the adult skeleton. csf1ra, however, has adopted unique roles in pigment cell patterning not seen in the second paralogue. We identify a unique noncoding element within csf1ra of fishes that is sufficient for controlling gene expression in pigment cells during development. As a role for Csf1r signaling in pigmentation is not observed in mammals or birds, it is likely that the overlapping roles of the two paralogues released functional constraints on csf1ra, allowing the signaling capacity of Csf1r to serve a novel function in the evolution of pigment pattern in fishes.


Asunto(s)
Desarrollo Embrionario , Proteínas Tirosina Quinasas/metabolismo , Homología de Secuencia de Aminoácido , Proteínas de Pez Cebra/metabolismo , Pez Cebra/embriología , Animales , Huesos/metabolismo , Dentición , Desarrollo Embrionario/genética , Elementos de Facilitación Genéticos/genética , Regulación del Desarrollo de la Expresión Génica , Modelos Biológicos , Mutación/genética , Fenotipo , Pigmentación/genética , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas Receptoras , Pez Cebra/genética , Proteínas de Pez Cebra/genética
17.
Development ; 147(18)2020 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-32958507

RESUMEN

The FaceBase Consortium was established by the National Institute of Dental and Craniofacial Research in 2009 as a 'big data' resource for the craniofacial research community. Over the past decade, researchers have deposited hundreds of annotated and curated datasets on both normal and disordered craniofacial development in FaceBase, all freely available to the research community on the FaceBase Hub website. The Hub has developed numerous visualization and analysis tools designed to promote integration of multidisciplinary data while remaining dedicated to the FAIR principles of data management (findability, accessibility, interoperability and reusability) and providing a faceted search infrastructure for locating desired data efficiently. Summaries of the datasets generated by the FaceBase projects from 2014 to 2019 are provided here. FaceBase 3 now welcomes contributions of data on craniofacial and dental development in humans, model organisms and cell lines. Collectively, the FaceBase Consortium, along with other NIH-supported data resources, provide a continuously growing, dynamic and current resource for the scientific community while improving data reproducibility and fulfilling data sharing requirements.


Asunto(s)
Investigación Dental/métodos , Huesos Faciales/fisiología , Cráneo/fisiología , Animales , Bases de Datos Factuales , Humanos , Reproducibilidad de los Resultados , Investigadores
18.
Artículo en Inglés | MEDLINE | ID: mdl-37553824

RESUMEN

Kryptolebias marmoratus (Kmar), a teleost fish of the order Cyprinodontiformes, has a suite of unique phenotypes and behaviors not observed in other fishes. Many of these phenotypes are discrete and highly plastic-varying over time within an individual, and in some cases reversible. Kmar and its interfertile sister species, K. hermaphroditus, are the only known self-fertile vertebrates. This unusual sexual mode has the potential to provide unique insights into the regulation of vertebrate sexual development, and also lends itself to genetics. Kmar is easily adapted to the lab and requires little maintenance. However, its internal fertilization and small clutch size limits its experimental use. To support Kmar as a genetic model, we compared alternative husbandry techniques to maximize recovery of early cleavage-stage embryos. We find that frequent egg collection enhances yield, and that protease treatment promotes the greatest hatching success. We completed a forward mutagenesis screen and recovered several mutant lines that serve as important tools for genetics in this model. Several will serve as useful viable recessive markers for marking crosses. Importantly, the mutant kissylips lays embryos at twice the rate of wild-type. Combining frequent egg collection with the kissylips mutant background allows for a substantial enhancement of early embryo yield. These improvements were sufficient to allow experimental analysis of early development and the successful mono- and bi-allelic targeted knockout of an endogenous tyrosinase gene with CRISPR/Cas9 nucleases. Collectively, these tools will facilitate modern developmental genetics in this fascinating fish, leading to future insights into the regulation of plasticity.

19.
Plant Cell ; 32(10): 3346-3369, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32769130

RESUMEN

Arabinogalactan proteins (AGPs) are a family of plant extracellular proteoglycans involved in many physiological events. AGPs are often anchored to the extracellular side of the plasma membrane and are highly glycosylated with arabinogalactan (AG) polysaccharides, but the molecular function of this glycosylation remains largely unknown. The ß-linked glucuronic acid (GlcA) residues in AG polysaccharides have been shown in vitro to bind to calcium in a pH-dependent manner. Here, we used Arabidopsis (Arabidopsis thaliana) mutants in four AG ß-glucuronyltransferases (GlcAT14A, -B, -D, and -E) to understand the role of glucuronidation of AG. AG isolated from glcat14 triple mutants had a strong reduction in glucuronidation. AG from a glcat14a/b/d triple mutant had lower calcium binding capacity in vitro than AG from wild-type plants. Some mutants had multiple developmental defects such as reduced trichome branching. glcat14a/b/e triple mutant plants had severely limited seedling growth and were sterile, and the propagation of calcium waves was perturbed in roots. Several of the developmental phenotypes were suppressed by increasing the calcium concentration in the growth medium. Our results show that AG glucuronidation is crucial for multiple developmental processes in plants and suggest that a function of AGPs might be to bind and release cell-surface apoplastic calcium.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Calcio/metabolismo , Galactanos/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Pleiotropía Genética , Glucurónidos/metabolismo , Mutación , Filogenia , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo
20.
Am J Med Genet A ; 191(7): 1994-2002, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37040531

RESUMEN

The Society for Craniofacial Genetics and Developmental Biology (SCGDB) held its 45th Annual Meeting at the Sanford Consortium for Regenerative Medicine at the University of California, San Diego on October 20th-21st, 2022. The meeting included presentation of the SCGDB Distinguished Scientists in Craniofacial Research Awards to Drs. Ralph Marcucio and Loydie Jerome-Majewska and four scientific sessions that highlighted new discoveries in signaling in craniofacial development, genomics of craniofacial development, human genetics of craniofacial development and translational and regenerative approaches in craniofacial biology. The meeting also included workshops on analysis of single cell RNA sequencing datasets and using human sequencing data from the Gabriella Miller Kids First Pediatric Research Program. There were 110 faculty and trainees in attendance that represent a diverse group of researchers from all career stages in the fields of developmental biology and genetics. The meeting, which also included outdoor poster presentations, provided opportunities for participant interactions and discussions, thus strengthening the SCGDB community.


Asunto(s)
Distinciones y Premios , Genómica , Niño , Humanos , Biología Evolutiva , Congresos como Asunto
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