Preschoolers who display extremely inhibited behavior are at risk for the development of anxiety disorders. However, behavioral inhibition (BI) is a multifaceted characteristic. Some children with BI are fearful when confronted by unfamiliar adults, peers, and objects; others are fearful when separated from their parents.
View Article and Find Full Text PDFGenomic regulation of cardiomyocyte differentiation is central to heart development and function. This study uses genetic loss-of-function human-induced pluripotent stem cell-derived cardiomyocytes to evaluate the genomic regulatory basis of the non-DNA-binding homeodomain protein HOPX. We show that HOPX interacts with and controls cardiac genes and enhancer networks associated with diverse aspects of heart development.
View Article and Find Full Text PDFDilated cardiomyopathy (DCM) is a common heart muscle disorder that frequently leads to heart failure, arrhythmias, and death. While DCM is often heritable, disease-causing mutations are identified in only ~30% of cases. In a forward genetic mutagenesis screen, we identified a novel zebrafish mutant, (), characterized by early-onset cardiomyopathy and craniofacial defects.
View Article and Find Full Text PDFBackground: Given the robust evidence base for the efficacy of evidence-based treatments targeting youth anxiety, researchers have advanced beyond efficacy outcome analysis to identify mechanisms of change and treatment directionality. Grounded in developmental transactional models, interventions for young children at risk for anxiety by virtue of behaviorally inhibited temperament often target parenting and child factors implicated in the early emergence and maintenance of anxiety. In particular, overcontrolling parenting moderates risk for anxiety among highly inhibited children, just as child inhibition has been shown to elicit overcontrolling parenting.
View Article and Find Full Text PDFIntroduction: Behavioral inhibition (BI) is a temperamental trait characterized by a bias to respond with patterns of fearful or anxious behavior when faced with unfamiliar situations, objects, or people. It has been suggested that children who are inhibited may experience early peer difficulties. However, researchers have yet to systematically compare BI versus typically developing children's observed asocial and social behavior in familiar, naturalistic settings.
View Article and Find Full Text PDFTransmembrane protein 161b (Tmem161b) was recently identified in multiple high-through-put phenotypic screens, including in fly, zebrafish, and mouse. In zebrafish, Tmem161b was identified as an essential regulator of cardiac rhythm. In mouse, Tmem161b shows conserved function in regulating cardiac rhythm but has also been shown to impact cardiac morphology.
View Article and Find Full Text PDFDuring development, the lymphatic vasculature forms as a second network derived chiefly from blood vessels. The transdifferentiation of embryonic venous endothelial cells (VECs) into lymphatic endothelial cells (LECs) is a key step in this process. Specification, differentiation and maintenance of LEC fate are all driven by the transcription factor Prox1, yet the downstream mechanisms remain to be elucidated.
View Article and Find Full Text PDFSonic hedgehog signaling regulates processes of embryonic development across multiple tissues, yet factors regulating context-specific Shh signaling remain poorly understood. Exome sequencing of families with polymicrogyria (disordered cortical folding) revealed multiple individuals with biallelic deleterious variants in , which encodes a multi-pass transmembrane protein of unknown function. null mice demonstrated holoprosencephaly, craniofacial midline defects, eye defects, and spinal cord patterning changes consistent with impaired Shh signaling, but were without limb defects, suggesting a CNS-specific role of Tmem161b.
View Article and Find Full Text PDFThe nucleoporin (NUP) ELYS, encoded by , is a large multifunctional protein with essential roles in nuclear pore assembly and mitosis. Using both larval and adult zebrafish models of hepatocellular carcinoma (HCC), in which the expression of an inducible mutant transgene () drives hepatocyte-specific hyperplasia and liver enlargement, we show that reducing gene dosage by 50% markedly decreases liver volume, while non-hyperplastic tissues are unaffected. We demonstrate that in the context of cancer, heterozygosity impairs nuclear pore formation, mitotic spindle assembly, and chromosome segregation, leading to DNA damage and activation of a Tp53-dependent transcriptional programme that induces cell death and cell cycle arrest.
View Article and Find Full Text PDFJ Cardiovasc Transl Res
April 2023
Remodeling of extracellular matrix proteins underlies the development of cardiovascular disease. Herein, we utilized a novel molecular probe, collagen hybridizing peptide (CHP), to target collagen molecular damage during atherogenesis. The thoracic aorta was dissected from ApoE mice that had been on a high-fat diet for 0-18 weeks.
View Article and Find Full Text PDFThe endocardium plays important roles in the development and function of the vertebrate heart; however, few molecular markers of this tissue have been identified and little is known about what regulates its differentiation. Here, we describe the Gt(SAGFF27C); Tg(4xUAS:egfp) line as a marker of endocardial development in zebrafish. Transcriptomic comparison between endocardium and pan-endothelium confirms molecular distinction between these populations and time-course analysis suggests differentiation as early as eight somites.
View Article and Find Full Text PDFThe development of a functional vasculature requires the coordinated control of cell fate, lineage differentiation and network growth. Cellular proliferation is spatiotemporally regulated in developing vessels, but how this is orchestrated in different lineages is unknown. Here, using a zebrafish genetic screen for lymphatic-deficient mutants, we uncover a mutant for the RNA helicase Ddx21.
View Article and Find Full Text PDFThe cavin proteins are essential for caveola biogenesis and function. Here, we identify a role for the muscle-specific component, Cavin4, in skeletal muscle T-tubule development by analyzing two vertebrate systems, mouse and zebrafish. In both models, Cavin4 localized to T-tubules, and loss of Cavin4 resulted in aberrant T-tubule maturation.
View Article and Find Full Text PDFMouse models of atherosclerosis have become effective resources to study atherogenesis, including the relationship between hemodynamics and lesion development. Computational methods aid the prediction of the in vivo hemodynamic environment in the mouse vasculature, but careful selection of inflow and outflow boundary conditions (BCs) is warranted to promote model accuracy. Herein, we investigated the impact of animal-specific versus reduced/idealized flow boundary conditions on predicted blood flow patterns in the mouse thoracic aorta.
View Article and Find Full Text PDFJ Cardiovasc Dev Dis
June 2021
The heart is laterally asymmetric. Not only is it positioned on the left side of the body but the organ itself is asymmetric. This patterning occurs across scales: at the organism level, through left-right axis patterning; at the organ level, where the heart itself exhibits left-right asymmetry; at the cellular level, where gene expression, deposition of matrix and proteins and cell behaviour are asymmetric; and at the molecular level, with chirality of molecules.
View Article and Find Full Text PDFBackground: Children classified as behaviorally inhibited (BI) are at risk for social anxiety. Risk for anxiety is moderated by both parental behavior and social-emotional competence. Grounded in developmental-transactional theory, the Turtle Program involves both parent and child treatment components delivered within the peer context.
View Article and Find Full Text PDFAlthough many studies show that peers influence the development of adolescent internalizing and externalizing difficulties, few have considered both internalizing and externalizing difficulties in the same study, and fewer have considered the contributions of parents. Using a longitudinal sample of 385 adolescents, the contributions of best friends' internalizing and externalizing difficulties (as assessed in Grade 6; G6: = 13.64 years; 53% female; 40% ethnic or racial minority) were examined as they predicted subsequent adolescent internalizing and externalizing difficulties (at G8); in addition, the moderating role of both maternal and paternal support (at G6) was explored.
View Article and Find Full Text PDFThe establishment of cardiac function in the developing embryo is essential to ensure blood flow and, therefore, growth and survival of the animal. The molecular mechanisms controlling normal cardiac rhythm remain to be fully elucidated. From a forward genetic screen, we identified a unique mutant, that displayed a specific cardiac arrhythmia phenotype.
View Article and Find Full Text PDFThe lymphatic vasculature develops primarily from pre-existing veins. A pool of lymphatic endothelial cells (LECs) first sprouts from cardinal veins followed by migration and proliferation to colonise embryonic tissues. Although much is known about the molecular regulation of LEC fate and sprouting during early lymphangiogenesis, we know far less about the instructive and permissive signals that support LEC migration through the embryo.
View Article and Find Full Text PDFEvid Based Pract Child Adolesc Ment Health
September 2020
Behavioral inhibition (BI) is a temperamental style that poses risk for later anxiety. Efficacious interventions have been developed for inhibited children, but their success depends on parent engagement. However, little is known regarding predictors of parent engagement in interventions for BI.
View Article and Find Full Text PDFThe correct assignment of cell fate within fields of multipotent progenitors is essential for accurate tissue diversification. The first lymphatic vessels arise from pre-existing veins after venous endothelial cells become specified as lymphatic progenitors. Prox1 specifies lymphatic fate and labels these progenitors; however, the mechanisms restricting Prox1 expression and limiting the progenitor pool remain unknown.
View Article and Find Full Text PDFBackground: During heart morphogenesis, the cardiac chambers undergo ballooning: a process involving regionalized elongation of cardiomyocytes. Cardiomyocyte shape changes require reorganization of the actin cytoskeleton; however, the genetic regulation of this process is not well understood.
Results: From a forward genetic screen, we identified the zebrafish uq mutant which manifests chamber ballooning defects.
Behavioral inhibition (BI), a temperament trait characterized by fear and wariness in novel situations, has been identified as a risk factor for later social reticence and avoidance of peer interactions. However, the ability to regulate fearful responses to novelty may disrupt the link between BI and socially reticent behavior. The present study examined how and whether both behaviorally-manifested and physiological indices of emotion regulation moderate the relation between BI and later social reticence.
View Article and Find Full Text PDFAtrial natriuretic peptide () and brain natriuretic peptide () form a gene cluster with expression in the chambers of the developing heart. Despite restricted expression, a function in cardiac development has not been demonstrated by mutant analysis. This is attributed to functional redundancy; however, their genomic location has impeded formal analysis.
View Article and Find Full Text PDFForces play diverse roles in vascular development, homeostasis and disease. VE-cadherin at endothelial cell-cell junctions links the contractile acto-myosin cytoskeletons of adjacent cells, serving as a tension-transducer. To explore tensile changes across VE-cadherin in live zebrafish, we tailored an optical biosensor approach, originally established in vitro.
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