Mutation in utp15 disrupts vascular patterning in a p53-dependent manner in zebrafish embryos

Mining the Penicillium expansum Genome for Virulence Genes: A Functional-Based Approach to Discover Novel Loci Mediating Blue Mold Decay of Apple Fruit

Blue mold, a postharvest disease of pome fruits, is caused by the filamentous fungus Penicillium expansum. In addition to the economic losses caused by P. expansum, food safety can be compromised, as this pathogen is mycotoxigenic. In this study, forward and reverse genetic approaches were used to identify genes involved in blue mold infection in apple fruits. For this, we generated a random T-DNA insertional mutant library. A total of 448 transformants were generated and screened for the reduced decay phenotype on apples. Of these mutants, six (T-193, T-275, T-434, T-588, T-625, and T-711) were selected for continued studies and five unique genes were identified of interest. In addition, two deletion mutants (Δt-625 and Δt-588) and a knockdown strain (t-434KD) were generated for three loci. Data show that the ∆t-588 mutant phenocopied the T-DNA insertion mutant and had virulence penalties during apple fruit decay. We hypothesize that this locus encodes a glyoxalase due to bioinformatic predictions, thus contributing to reduced colony diameter when grown in methylglyoxal (MG). This work presents novel members of signaling networks and additional genetic factors that regulate fungal virulence in the blue mold fungus during apple fruit decay.

Genomic basis of evolutionary adaptation in a warm-blooded fish

Few fishes have evolved elevated body temperatures compared with ambient temperatures, and only in opah (Lampris spp) is the entire body affected. To understand the molecular basis of endothermy, we analyzed the opah genome and identified 23 genes with convergent amino acid substitutions across fish, birds, and mammals, including slc8b1, which encodes the mitochondrial Na⁺/Ca²⁺ exchanger and is essential for heart function and metabolic heat production. Among endothermic fishes, 44 convergent genes with suggestive metabolic functions were identified, such as glrx3, encoding a crucial protein for hemoglobin maturation. Numerous genes involved in the production and retention of metabolic heat were also found to be under positive selection. Analyses of opah's unique inner-heat-producing pectoral muscle layer (PMI), an evolutionary key innovation, revealed that many proteins were co-opted from dorsal swimming muscles for thermogenesis and oxidative phosphorylation. Thus, the opah genome provides valuable resources and opportunities to uncover the genetic basis of thermal adaptations in fish.

Identification of key genes in osteosarcoma - before and after CDK7 treatment

BACKGROUND

Osteosarcoma is one of the most common bone tumors, with a high degree of malignancy and a poor prognosis. Recent studies have shown that THZ2, a cyclin-dependent kinase 7 inhibitor, can exhibit strong antibone tumor effects in vivo and in vitro by inhibiting transcriptional activity. In this study, by screening the differentially expressed genes (DEGs) of osteosarcoma cells before and after THZ2 treatment, it provides new possible targets for the future targeted therapy of osteosarcoma.

METHODS

Download the gene expression profile of GSE134603 from the Gene Expression Omnibus database, and use the R software package "limma Geoquery" to screen DEGs. DAVID database was used for gene ontology analysis of DEGs. Use search tool for the retrieval of interacting genes online database and Cytoscape software to construct protein-protein interaction network. Use the "MCODE" plugin in Cytoscape to analyze key molecular complexes (module) of DEGs, and use the "Cluego" plugin to perform Kyoto Encyclopedia of Genes and Genomes enrichment analysis on module genes. The Hub gene is selected from the genes in DEGs that coexist in the top 30 Degree and the Kyoto Encyclopedia of Genes and Genomes pathway.

RESULTS

A total of 1033 DEGs were screened, including 800 up-regulated genes and 233 down-regulated genes. Gene ontology analysis showed that cell component is the main enrichment area of DEGs, mainly in the nucleus, cytoplasm, and nucleoplasm. In addition, in molecular function analysis, DEGs are mainly enriched in the process of protein binding. In biological process analysis, changes in DEGs can also be observed in transcription and regulation using DNA as a template. Twenty-nine module genes are enriched in the Ribosome biogenesis in eukaryotes pathway. Finally, 4 key genes are drawn: essential for mitotic growth 1, U3 SnoRNP protein 3 homolog, U3 small nucleolar RNA-associated protein 15 homolog, and WD repeat domain 3.

CONCLUSION

This study found that the 4 genes essential for mitotic growth 1, U3 SnoRNP protein 3 homolog, U3 small nucleolar RNA-associated protein 15 homolog, WD repeat domain 3, and the ribosome biogenesis in eukaryotes pathway play a very important role in the occurrence and development of osteosarcoma, and can become a new target for molecular targeted therapy of osteosarcoma in the future.

Vegfaa instructs cardiac muscle hyperplasia in adult zebrafish

During heart development and regeneration, coronary vascularization is tightly coupled with cardiac growth. Although inhibiting vascularization causes defects in the innate regenerative response of zebrafish to heart injury, angiogenic signals are not known to be sufficient for triggering regeneration events. Here, by using a transgenic reporter strain, we found that regulatory sequences of the angiogenic factor vegfaa are active in epicardial cells of uninjured animals, as well as in epicardial and endocardial tissue adjacent to regenerating muscle upon injury. Additionally, we find that induced cardiac overexpression of vegfaa in zebrafish results in overt hyperplastic thickening of the myocardial wall, accompanied by indicators of angiogenesis, epithelial-to-mesenchymal transition, and cardiomyocyte regeneration programs. Unexpectedly, vegfaa overexpression in the context of cardiac injury enabled ectopic cardiomyogenesis but inhibited regeneration at the site of the injury. Our findings identify Vegfa as one of a select few known factors sufficient to activate adult cardiomyogenesis, while also illustrating how instructive factors for heart regeneration require spatiotemporal control for efficacy.

Tbx20 drives cardiac progenitor formation and cardiomyocyte proliferation in zebrafish

Tbx20 is a T-box transcription factor that plays essential roles in the development and maintenance of the heart. Although it is expressed by cardiac progenitors in all species examined, an involvement of Tbx20 in cardiac progenitor formation in vertebrates has not been previously described. Here we report the identification of a zebrafish tbx20 mutation that results in an inactive, truncated protein lacking any functional domains. The cardiac progenitor population is strongly diminished in this mutant, leading to the formation of a small, stretched-out heart. We found that overexpression of Tbx20 results in an enlarged heart with significantly more cardiomyocytes. Interestingly, this increase in cell number is caused by both enhanced cardiac progenitor cell formation and the proliferation of differentiated cardiomyocytes, and is dependent upon the activity of Tbx20's T-box and transcription activation domains. Together, our findings highlight a previously unappreciated role for Tbx20 in promoting cardiac progenitor formation in vertebrates and reveal a novel function for its activation domain in cardiac cell proliferation during embryogenesis.

Identification of vascular disruptor compounds by analysis in zebrafish embryos and mouse embryonic endothelial cells

To identify vascular disruptor compounds (VDCs), this study utilized an in vivo zebrafish embryo vascular model in conjunction with a mouse endothelial cell model to screen a subset of the U.S. Environmental Protection Agency (EPA) ToxCast Phase I chemical inventory. In zebrafish, 161 compounds were screened and 34 were identified by visual inspection as VDCs, of which 28 were confirmed as VDCs by quantitative image analysis. Testing of the zebrafish VDCs for their capacity to inhibit endothelial tube formation in the murine yolk-sac-derived endothelial cell line C166 identified 22 compounds that both disrupted zebrafish vascular development and murine endothelial in vitro tubulogenesis. Putative molecular targets for the VDCs were predicted using EPA's Toxicological Prioritization Index tool and a VDC signature based on a proposed adverse outcome pathway for developmental vascular toxicity. In conclusion, our screening approach identified 22 novel VDCs, some of which were active at nanomolar concentrations.

The synaptic proteins β-neurexin and neuroligin synergize with extracellular matrix-binding vascular endothelial growth factor a during zebrafish vascular development

OBJECTIVE

The goal of this study was to determine the in vivo functions of the synaptic proteins neurexins and neuroligins in embryonic vascular system development using zebrafish as animal model.

METHODS AND RESULTS

In the present study, we show that the knockdown of the α-form of neurexin 1a induces balance defects and reduced locomotory activity, whereas β-neurexin 1a and neuroligin 1 morphants present defects in sprouting angiogenesis and vascular remodeling, in particular in the caudal plexus and subintestinal vessels. Coinjection of low doses of morpholinos for β-neurexin 1a and neuroligin 1 together or in combination with morpholinos targeting the -heparin--binding isoforms of vascular endothelial growth factor A (encoded by the VEGFAb gene) recapitulates the observed abnormalities, suggesting synergistic activity of these molecules. Similar coinjection experiments with morpholinos, targeting the enzyme heparan sulfate 6-O-sulfotransferase 2, confirm the presence of a functional correlation between extracellular matrix maturation and β-neurexin 1a or neuroligin 1.

CONCLUSIONS

Our data represent the first in vivo evidence of the role of neurexin and neuroligin in embryonic blood vessel formation and provide insights into their mechanism of action.