Read by QxMD icon Read

C.elegans embryo

Sarah Edie, Norann A Zaghloul, Carmen C Leitch, Donna K Klinedinst, Janette Lebron, Joey F Thole, Andrew S McCallion, Nicholas Katsanis, Roger H Reeves
Trisomy for human chromosome 21 (Hsa21) results in Down syndrome (DS), one of the most genetically complex conditions compatible with human survival. Assessment of the physiological consequences of dosage-driven overexpression of individual Hsa21 genes during early embryogenesis and the resulting contributions to DS pathology in mammals are not tractable in a systematic way. A recent study looked loss-of-function of C. elegans orthologues of Hsa21 genes and identified ten candidates with behavioral phenotypes, but the equivalent over-expression experiment has not been done...
May 14, 2018: G3: Genes—Genomes—Genetics
Chutian Ge, Jian Ye, Ceri Weber, Wei Sun, Haiyan Zhang, Yingjie Zhou, Cheng Cai, Guoying Qian, Blanche Capel
Temperature-dependent sex determination is a notable model of phenotypic plasticity. In many reptiles, including the red-eared slider turtle Trachemys scripta elegans ( T. scripta ), the individual's sex is determined by the ambient temperature during egg incubation. In this study, we show that the histone H3 lysine 27 (H3K27) demethylase KDM6B exhibits temperature-dependent sexually dimorphic expression in early T. scripta embryos before the gonad is distinct. Knockdown of Kdm6b at 26°C (a temperature at which all offspring develop into males) triggers male-to-female sex reversal in >80% of surviving embryos...
May 11, 2018: Science
Melina J Scholze, Kévin S Barbieux, Alessandro De Simone, Mathilde Boumasmoud, Camille C N Süess, Ruijia Wang, Pierre Gönczy
Asymmetric division is crucial for embryonic development and stem cell lineages. In the one-cell C. elegans embryo, a contractile cortical actomyosin network contributes to asymmetric division by segregating PAR proteins to discrete cortical domains. Here, we discovered that the plasma membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP2 ) localizes to polarized dynamic structures in C. elegans zygotes, distributing in a PAR-dependent manner along the anterior-posterior (A-P) embryonic axis. PIP2 cortical structures overlap with F-actin, and coincide with the actin regulators RHO-1, CDC-42 as well as ECT-2...
May 3, 2018: Development
Osama Refai, Ryan B Smit, SarahBeth Votra, David Pruyne, Paul E Mains
The cytoskeleton is the basic machinery that drives many morphogenetic events. Elongation of the C. elegans embryo from a spheroid into a long, thin larva initially results from actomyosin contractility, mainly in the lateral epidermal seam cells, while the corresponding dorsal and ventral epidermal cells play a more passive role. This is followed by a later elongation phase involving muscle contraction. Early elongation is mediated by parallel genetic pathways involving LET-502/Rho kinase and MEL-11/MYPT myosin phosphatase in one pathway and FEM-2/PP2c phosphatase and PAK-1/p21 activated kinase in another...
May 2, 2018: G3: Genes—Genomes—Genetics
Kunal Baxi, Carlos E de Carvalho
The nematode Caenorhabditis elegans (C. elegans) is a model system that is widely used to study longevity and developmental pathways. Such studies are facilitated by the transparency of the animal, the ability to do forward and reverse genetic assays, the relative ease of generating fluorescently labeled proteins, and the use of fluorescent dyes that can either be microinjected into the early embryo or incorporated into its food (E. coli strain OP50) to label cellular organelles (e.g. 9-diethylamino-5H-benzo(a)phenoxazine-5-one and (3-{2-[(1H,1'H-2,2'-bipyrrol-5-yl-kappaN(1))methylidene]-2H-pyrrol-5-yl-kappaN}-N-[2-(dimethylamino)ethyl]propanamidato)(difluoro)boron)...
April 13, 2018: Journal of Visualized Experiments: JoVE
Zi Wang, Dali Wang, Chengcheng Li, Yichi Xu, Husheng Li, Zhirong Bao
Motivation: Cell movement in the early phase of C. elegans development is regulated by a highly complex process in which a set of rules and connections are formulated at distinct scales. Previous efforts have demonstrated that agent-based, multi-scale modeling systems can integrate physical and biological rules and provide new avenues to study developmental systems. However, the application of these systems to model cell movement is still challenging and requires a comprehensive understanding of regulatory networks at the right scales...
April 25, 2018: Bioinformatics
Abigail R Gerhold, Vincent Poupart, Jean-Claude Labbé, Paul S Maddox
The spindle assembly checkpoint (SAC) is a conserved mitotic regulator that preserves genome stability by monitoring kinetochore-microtubule attachments and blocking anaphase onset until chromosome bi-orientation is achieved. Despite its central role in maintaining mitotic fidelity, the ability of the SAC to delay mitotic exit in the presence of kinetochore-microtubule attachment defects (SAC "strength") appears to vary widely. How different cellular aspects drive this variation remains largely unknown...
April 24, 2018: Molecular Biology of the Cell
Philipp H Schiffer, Avital L Polsky, Alison G Cole, Julia I R Camps, Michael Kroiher, David H Silver, Vladislav Grishkevich, Leon Anavy, Georgios Koutsovoulos, Tamar Hashimshony, Itai Yanai
The evolution of development has been studied through the lens of gene regulation by examining either closely related species or extremely distant animals of different phyla. In nematodes, detailed cell- and stage-specific expression analyses are focused on the model Caenorhabditis elegans , in part leading to the view that the developmental expression of gene cascades in this species is archetypic for the phylum. Here, we compared two species of an intermediate evolutionary distance: the nematodes C. elegans (clade V) and Acrobeloides nanus (clade IV)...
April 6, 2018: Proceedings of the National Academy of Sciences of the United States of America
Tobias Wiesenfahrt, Jingjie Duanmu, Frances Snider, Don Moerman, Vinci Au, Erica Li-Leger, Stephane Flibotte, Dylan M Parker, Craig J Marshall, Erin Osborne Nishimura, Paul E Mains, James D McGhee
The ELT-2 GATA factor normally functions in differentiation of the C. elegans endoderm, downstream of endoderm specification. We have previously shown that, if ELT-2 is expressed sufficiently early, it is also able to specify the endoderm and to replace all other members of the core GATA-factor transcriptional cascade (END-1, END-3, ELT-7). However, such rescue requires multiple copies (and presumably overexpression) of the end-1p::elt-2 cDNA transgene; a single copy of the transgene does not rescue. We have made this observation the basis of a genetic screen to search for genetic modifiers that allow a single copy of the end-1p::elt-2 cDNA transgene to rescue the lethality of the end-1 end-3 double mutant...
March 28, 2018: G3: Genes—Genomes—Genetics
Peter Insley, Shai Shaham
The Caenorhabditis elegans cell lineage is nearly invariant. Whether this stereotyped cell-division pattern promotes reproducibility in cell shapes/positions is not generally known, as manual spatiotemporal cell-shape/position alignments are labor-intensive, and fully-automated methods are not described. Here, we report automated algorithms for spatiotemporal alignments of C. elegans embryos from pre-morphogenesis to motor-activity initiation. We use sparsely-labeled green-fluorescent nuclei and a pan-nuclear red-fluorescent reporter to register consecutive imaging time points and compare embryos...
2018: PloS One
Mahlet D Mersha, Karla R Sanchez, Murali K Temburni, Harbinder S Dhillon
Bisphenols, such as bisphenol A (BPA) and bisphenol S (BPS) are polymerizing agents widely used in the production of plastics and numerous everyday-use products. Based on their chemical structure and estradiol-like biological properties, they have been classified as endocrine disrupting compounds (EDC). Long-term exposure to EDCs, even at low doses, has been linked to various health defects including cancer, behavioral disorders and infertility, with greater vulnerability indicated during early developmental periods...
March 6, 2018: Journal of Visualized Experiments: JoVE
Chi-Kuo Hu, Anne Brunet
The African turquoise killifish has recently gained significant traction as a new research organism in the aging field. Our understanding of aging has strongly benefited from canonical research organisms-yeast, C. elegans, Drosophila, zebrafish, and mice. Many characteristics that are essential to understand aging-for example, the adaptive immune system or the hypothalamo-pituitary axis-are only present in vertebrates (zebrafish and mice). However, zebrafish and mice live more than 3 years and their relatively long lifespans are not compatible with high-throughput studies...
March 24, 2018: Aging Cell
Long Chen, Vincy Wing Sze Ho, Ming-Kin Wong, Xiaotai Huang, Lu-Yan Chan, Hon Chun Kaoru Ng, Xiaoliang Ren, Hong Yan, Zhongying Zhao
Intercellular signaling interaction plays a key role in breaking fate symmetry during animal development. Identification of the signaling interaction at cellular resolution is technically challenging, especially in a developing embryo. Here we develop a platform that allows automated inference and validation of signaling interaction for every cell cycle of C. elegans embryogenesis. This is achieved by generation of a systems-level cell contact map that consists of 1,114 highly confident intercellular contacts by modeling analysis and is validated through cell membrane labeling coupled with cell lineage analysis...
March 22, 2018: Genetics
A De Simone, A Spahr, C Busso, P Gönczy
Microtubule asters must be positioned precisely within cells. How forces generated by molecular motors such as dynein are integrated in space and time to enable such positioning remains unclear. In particular, whereas aster movements depend on the drag caused by cytoplasm viscosity, in vivo drag measurements are lacking, precluding a thorough understanding of the mechanisms governing aster positioning. Here, we investigate this fundamental question during the migration of asters and pronuclei in C. elegans zygotes, a process essential for the mixing of parental genomes...
March 5, 2018: Nature Communications
Daniel P Reich, Katarzyna M Tyc, Brenda L Bass
Cellular dsRNAs are edited by adenosine deaminases that act on RNA (ADARs). While editing can alter mRNA-coding potential, most editing occurs in noncoding sequences, the function of which is poorly understood. Using dsRNA immunoprecipitation (dsRIP) and RNA sequencing (RNA-seq), we identified 1523 regions of clustered A-to-I editing, termed editing-enriched regions (EERs), in four stages of Caenorhabditis elegans development, often with highest expression in embryos. Analyses of small RNA-seq data revealed 22- to 23-nucleotide (nt) siRNAs, reminiscent of viral siRNAs, that mapped to EERs and were abundant in adr-1;adr-2 mutant animals...
February 1, 2018: Genes & Development
Ye Hong, Remi Sonneville, Bin Wang, Viktor Scheidt, Bettina Meier, Alexander Woglar, Sarah Demetriou, Karim Labib, Verena Jantsch, Anton Gartner
Faithful chromosome segregation and genome maintenance requires the removal of all DNA bridges that physically link chromosomes before cells divide. Using C. elegans embryos we show that the LEM-3/Ankle1 nuclease defines a previously undescribed genome integrity mechanism by processing DNA bridges right before cells divide. LEM-3 acts at the midbody, the structure where abscission occurs at the end of cytokinesis. LEM-3 localization depends on factors needed for midbody assembly, and LEM-3 accumulation is increased and prolonged when chromatin bridges are trapped at the cleavage plane...
February 20, 2018: Nature Communications
Shi-Lung Lin, Shao-Yao Ying
MicroRNAs (miRNAs), small single-stranded regulatory RNAs capable of interfering with intracellular messenger RNAs (mRNAs) that contain either complete or partial complementarity, are useful for the design of new therapies against cancer polymorphism and viral mutation. Numerous miRNAs have been reported to induce RNA interference (RNAi), a post-transcriptional gene-silencing mechanism. Recent evidence also indicates that they are involved in the transcriptional regulation of genome activities. They were first discovered in Caenorhabditis elegans as native RNA fragments that modulate a wide range of genetic regulatory pathways during embryonic development, and are now recognized as small gene silencers transcribed from the noncoding regions of a genome...
2018: Methods in Molecular Biology
John Isaac Murray
The convergence of developmental biology and modern genomics tools brings the potential for a comprehensive understanding of developmental systems. This is especially true for the Caenorhabditis elegans embryo because its small size, invariant developmental lineage, and powerful genetic and genomic tools provide the prospect of a cellular resolution understanding of messenger RNA (mRNA) expression and regulation across the organism. We describe here how a systems biology framework might allow large-scale determination of the embryonic regulatory relationships encoded in the C...
January 25, 2018: Wiley Interdisciplinary Reviews. Developmental Biology
Sarah Bianchi, Kacper B Rogala, Nicola J Dynes, Manuel Hilbert, Sebastian A Leidel, Michel O Steinmetz, Pierre Gönczy, Ioannis Vakonakis
Centrioles are microtubule-based organelles that organise the microtubule network and seed the formation of cilia and flagella. New centrioles assemble through a step-wise process dependent notably on the centriolar protein SAS-5 in Caenorhabditis elegans SAS-5 and its functional homologues in other species form oligomers that bind the centriolar proteins SAS-6 and SAS-4, thereby forming an evolutionarily conserved structural core at the onset of organelle assembly. Here, we report a novel interaction of SAS-5 with microtubules...
January 24, 2018: Molecular Biology of the Cell
Aurore-Cécile Valfort, Caroline Launay, Marie Sémon, Marie Delattre
Asymmetric cell division is essential to generate cellular diversity. In many animal cells, the cleavage plane lies perpendicular to the mitotic spindle, and it is the spindle positioning that dictates the size of the daughter cells. Although some properties of spindle positioning are conserved between distantly related model species and different cell types, little is known of the evolutionary robustness of the mechanisms underlying this event. We recorded the first embryonic division of 42 species of nematodes closely related to Caenorhabditis elegans, which is an excellent model system to study the biophysical properties of asymmetric spindle positioning...
January 2018: PLoS Biology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"