scholarly journals Functional in vivo characterization of sox10 enhancers in neural crest and melanoma development

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Rebecca L. Cunningham ◽  
Eva T. Kramer ◽  
Sophia K. DeGeorgia ◽  
Paula M. Godoy ◽  
Anna P. Zarov ◽  
...  
Keyword(s):  
Neural Crest ◽  
High Specificity ◽  
Open Chromatin ◽  
Genomic Locus ◽  
Cancer Models ◽  
Active Enhancer ◽  
Egfp Reporter ◽  
Melanoma Model ◽  
In Vivo Characterization

AbstractThe role of a neural crest developmental transcriptional program, which critically involves Sox10 upregulation, is a key conserved aspect of melanoma initiation in both humans and zebrafish, yet transcriptional regulation of sox10 expression is incompletely understood. Here we used ATAC-Seq analysis of multiple zebrafish melanoma tumors to identify recurrently open chromatin domains as putative melanoma-specific sox10 enhancers. Screening in vivo with EGFP reporter constructs revealed 9 of 11 putative sox10 enhancers with embryonic activity in zebrafish. Focusing on the most active enhancer region in melanoma, we identified a region 23 kilobases upstream of sox10, termed peak5, that drives EGFP reporter expression in a subset of neural crest cells, Kolmer-Agduhr neurons, and early melanoma patches and tumors with high specificity. A ~200 base pair region, conserved in Cyprinidae, within peak5 is required for transgenic reporter activity in neural crest and melanoma. This region contains dimeric SoxE/Sox10 dimeric binding sites essential for peak5 neural crest and melanoma activity. We show that deletion of the endogenous peak5 conserved genomic locus decreases embryonic sox10 expression and disrupts adult stripe patterning in our melanoma model background. Our work demonstrates the power of linking developmental and cancer models to better understand neural crest identity in melanoma.

scholarly journals Functional in vivo characterization of zebrafish sox10 enhancers in melanoma and neural crest

2020 ◽  
Author(s):  
Rebecca L. Cunningham ◽  
Eva T. Kramer ◽  
Sophia K. DeGeorgia ◽  
Shayana Seneviratne ◽  
Vadim Grigura ◽  
...  
Keyword(s):  
Neural Crest ◽  
Epigenetic Regulation ◽  
High Specificity ◽  
Open Chromatin ◽  
Transcriptional Enhancer ◽  
Reporter Expression ◽  
Transgenic Lines ◽  
In Vivo Characterization

AbstractThe re-emergence of a neural crest transcriptional program, including Sox10 upregulation, is a key step in melanoma initiation in humans and zebrafish. We hypothesize that epigenetic regulation of sox10 modulates melanoma initiation. ATAC-Seq analysis of zebrafish melanoma tumors identifies recurrently open chromatin domains near sox10. Reporter constructs for each putative sox10 enhancer were examined in zebrafish embryos for neural crest activity and in stable transgenic lines for melanoma activity. One element, peak5 (23 kilobases upstream of sox10), drives EGFP reporter expression in a subset of neural crest cells, Kolmer-Agduhr neurons, and early melanoma patches and tumors with high specificity. A ∼200 bp region, conserved across the Cyprinidae family (fish), is required for peak5 activity in neural crest and melanoma, and contains dimeric SoxE binding sites essential for neural crest activity. Our work identifies a novel melanoma transcriptional enhancer, expanding our knowledge of epigenetic regulation of neural crest identity in melanoma.

scholarly journals GeneWeld: a method for efficient targeted integration directed by short homology

2018 ◽  
Author(s):  
Wesley A. Wierson ◽  
Jordan M. Welker ◽  
Maira P. Almeida ◽  
Carla M. Mann ◽  
Dennis A. Webster ◽  
...  
Keyword(s):  
Genome Engineering ◽  
High Efficiency ◽  
High Specificity ◽  
Strand Break ◽  
Double Strand Break ◽  
Genomic Locus ◽  
Multiple Loci ◽  
Integration Strategy ◽  
Targeted Integration

AbstractChoices for genome engineering and integration involve high efficiency with little or no target specificity or high specificity with low activity. Here, we describe a targeted integration strategy, called GeneWeld, and a vector series for gene tagging, pGTag (plasmids forGeneTagging), which promote highly efficient and precise targeted integration in zebrafish embryos, pig fibroblasts, and human cells utilizing the CRISPR/Cas9 system. Our work demonstrates thatin vivotargeting of a genomic locus of interest with CRISPR/Cas9 and a donor vector containing as little as 24 to 48 base pairs of homology directs precise and efficient knock-in when the homology arms are exposed with a double strand breakin vivo. Our results suggest that the length of homology is not important in the design of knock-in vectors but rather how the homology is presented to a double strand break in the genome. Given our results targeting multiple loci in different species, we expect the accompanying protocols, vectors, and web interface for homology arm design to help streamline gene targeting and applications in CRISPR and TALEN compatible systems.

A Physiologic Regulator of Collagen-Induced Platelet Aggregation: Inhibition by Clq

1981 ◽  
Vol 45 (02) ◽  
pp. 110-115 ◽  
Author(s):  
György Csákó ◽  
Eva A Suba
Keyword(s):  
Platelet Aggregation ◽  
Human Platelet ◽  
Platelet Reactivity ◽  
High Specificity ◽  
Turbidimetric Method ◽  
Specific Manner ◽  
Aggregation Inhibition ◽  
Different Tissues

SummaryPlatelet aggregations were studied by a turbidimetric method in citrated human platelet-rich plasmas (PRP) in vitro. Human Clq inhibited the aggregations caused by collagens derived from different tissues and species. Clq was needed by weight in comparable quantities to collagen for neutralizing the aggregating effect. The dependence of the inhibitory reaction on the preincubation of platelets with Clq and the differences in the occurrence of aggregating substances in supernatants of PRP triggered with collagen in the presence or absence of Clq, confirmed that Clq exerts its effect by preventing fixation of collagen to platelets. In addition, the high specificity of the inhibitory action of Clq for collagen-induced platelet aggregation was demonstrated by results obtained for testing a variety of aggregating agents in combination with Clq and/or collagen.Since normal concentrations of Clq in the blood are in the range of inhibitory doses of Clq for collagen-induced platelet aggregations in vitro and upon activation of complement Clq is known to dissociate from Cl, it is proposed that Clq may participate in a highly specific manner in regulating platelet reactivity to collagen in vivo.

The truncated somatostatin receptor sst5TMD4 stimulates the production of pro-angiogenic factors in in vitro and in vivo breast cancer models

2014 ◽  
Author(s):  
Raul M Luque ◽  
Mario Duran-Prado ◽  
David Rincon-Fernandez ◽  
Marta Hergueta-Redondo ◽  
Michael D Culler ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Somatostatin Receptor ◽  
Angiogenic Factors ◽  
Cancer Models

Evaluation of Potent Isoquinoline-Based Thiosemicarbazone Antiproliferatives Against Solid Tumor Models

2019 ◽  
Author(s):  
Daniel Sun ◽  
Soumya Poddar ◽  
Roy D. Pan ◽  
Juno Van Valkenburgh ◽  
Ethan Rosser ◽  
...  
Keyword(s):  
Solid Tumor ◽  
Small Cell Lung Carcinoma ◽  
Single Agent ◽  
Resistance Mechanisms ◽  
Tumor Models ◽  
Cell Lung Carcinoma ◽  
Adaptive Resistance ◽  
Cancer Models ◽  
Nanomolar Range

The lead compound, an ⍺-N-heterocyclic carboxaldehyde thiosemicarbazone <b>HCT-13</b>, was highly potent against a panel of pancreatic, small cell lung carcinoma, and prostate cancer models, with IC<sub>90</sub> values in the low-to-mid nanomolar range.<b> </b>We show that the cytotoxicity of <b>HCT-13</b> is copper-dependent, that it acts as a copper ionophore, induces production of reactive oxygen species (ROS), and promotes mitochondrial dysfunction and S-phase arrest. Lastly, DNA damage response/replication stress response (DDR/RSR) pathways, specifically Ataxia-Telangiectasia Mutated (ATM) and Rad3-related protein kinase (ATR), were identified as actionable adaptive resistance mechanisms following <b>HCT-13 </b>treatment. Taken together, <b>HCT-13 </b>is potent against solid tumor models and warrants <i>in vivo</i> evaluation against aggressive tumor models, either as a single agent or as part of a combination therapy.

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