Biological Activity and Stability of Aeruginosamides from Cyanobacteria.

Aeruginosamides (AEGs) are classified as cyanobactins, ribosomally synthesized peptides with post-translational modifications. They have been identified in cyanobacteria of genera , , and . In this work, the new data on the in vitro activities of three AEG variants, AEG A, AEG625 and AEG657, and their interactions with metabolic enzymes are reported.

De Novo Profiling of Long Non-Coding RNAs Involved in MC-LR-Induced Liver Injury in Whitefish: Discovery and Perspectives.

Microcystin-LR (MC-LR) is a potent hepatotoxin for which a substantial gap in knowledge persists regarding the underlying molecular mechanisms of liver toxicity and injury. Although long non-coding RNAs (lncRNAs) have been extensively studied in model organisms, our knowledge concerning the role of lncRNAs in liver injury is limited. Given that lncRNAs show low levels of sequence conservation, their role becomes even more unclear in non-model organisms without an annotated genome, like whitefish ().

Luciferase reporter assay for small-molecule inhibitors of MIR92b-3p function: Screening cyanopeptolins produced by Nostoc from the Baltic Sea.

We developed a cell sensor that detects the liver cancer-specific microRNA MIR92b-3p, involved in hepatocellular carcinoma development and hepatitis C virus infection. To validate our small-molecule screen that employs a Huh7 human hepatoma cell line stably transfected with a pmirGLO vector containing dual luciferase reporters, we used i) a MIR92b-3p antisense or a MIR92b-3p mimicking agent (concentrations from 0.1 pM to 100 nM), ii) expression of XIST, a long non-coding RNA that is a cellular target of MIR92b, and iii) ectopic expression of Luc2 luciferase.

Molecular characterization of the cyclin-dependent protein kinase 6 in whitefish (Coregonus lavaretus) and its potential interplay with miR-34a.

Cyclin-dependent protein kinase 6 (CDK6) plays a pivotal role in the regulation of the cell cycle and cell proliferation in mammals, and disruption of its expression by various microRNAs has been implicated in the pathogenesis of multiple human cancers. In mammals, miR-34a acts as a downstream effector of p53, and thus indirectly targets Cdk6, abrogating its effects. However, no studies have been done so far to examine the mechanistic involvement of miR-34a in the silencing of cdk6 in fish.

In vivo miRNA delivery in whitefish: Synthetic MiR92b-3p uptake and the efficacy of gene expression silencing.

The delivery of short snippets of RNA, such as synthetic miRNA agents, is an essential step for achieving RNA-mediated knockdown, which has not been studied in sufficient detail in fish. Our results indicate that a MiR92b-3p mimic may be effectively delivered via intraperitoneal injection to the spleen and the liver of whitefish, and that it likely achieves functionality without causing any apparent toxic effects in the challenged animals. We report the novel finding that the MiR92b-3p mimic reduced the in vivo liver mRNA expression levels of its putative pro-apoptotic targets (p53, cdkn1a, and pcna), and important metabolic genes, e.

Feed contamination with zearalenone promotes growth but affects the immune system of rainbow trout.

To investigate the effects of feed contamination with zearalenone (ZEN) at the current European Commission (EC) guidance value (2 mg⋅kg feed) on the growth and health of rainbow trout, we performed a long-term feeding trial under aquaculture conditions. It started with the external feeding of the fish larvae, and continued for 96 weeks, at which point the fish had reached market size. To assess the growth of fish and their feeding efficiency throughout this period, the fish were regularly weighed and measured, and their feed consumption was monitored.

Microcystin-LR-Triggered Neuronal Toxicity in Whitefish Does Not Involve MiR124-3p.

Microcystin-LR (MC-LR) is a potent hepatotoxin that has also been pointed out of causing neurotoxicity, but the exact mechanisms of action still remain ambiguous and need to be elucidated. Data from studies on mammals show that pathology of astrocyte cells points to perturbations of microRNA signaling. Glial fibrillary acidic protein (GFAP), a neuronal cell/astrocyte-specific protein, and a microRNA-124-3p (MiR124-3p) are among putative triggers and regulators of neuronal cell/astrocyte reactivity.

Intraperitoneal exposure of whitefish to microcystin-LR induces rapid liver injury followed by regeneration and resilience to subsequent exposures.

To date, there has been no systematic approach comprehensively describing the sequence of pathological changes in fish during prolonged exposure to microcystin-LR (MC-LR). Towards this aim, juvenile whitefish individuals received an intraperitoneal injection with pure MC-LR, and the injection was repeated every week to maintain continuous exposure for 28days. During the exposure period, growth and condition of the fish were assessed based on biometric measurements.

Illumina Sequencing Reveals Aberrant Expression of MicroRNAs and Their Variants in Whitefish (Coregonus lavaretus) Liver after Exposure to Microcystin-LR.

Molecular analyses show that challenging fish with microcystin-LR (MC-LR) causes perturbations of microRNA (miRNA) signaling. However, the significance and scope of these alterations is currently unknown. To address this issue, we studied miRNA gene expression in the liver of juvenile whitefish, C.

miR-34a and bcl-2 expression in whitefish (Coregonus lavaretus) after microcystin-LR exposure.

Studies on mammals have demonstrated that the expression of miR-34a is associated with process of apoptosis in many cell types, by lowering expression of the anti-apoptotic protein Bcl-2. Despite the role of miR-34a, there is no data about the miR-34a:Bcl-2 interaction in lower vertebrates, especially in fish. In the current study, we determined the nucleotide sequence of miR-34a precursor, predicted its secondary structure, and shed light on the potential role of p53 in activation of miR-34a in whitefish, a salmonid fish species.