Exploring Excitotoxicity and Regulation of a Constitutively Active TRP Ca2+ Channel in Drosophila

Unregulated Ca2+ influx affects intracellular Ca2+ homoeostasis, which may lead to neuronal death. In Drosophila, following the activation of rhodopsin the TRP Ca2+ channel is open to mediate the light-dependent depolarization. A constitutively active TRP channel triggers the degeneration of TrpP365/+ photoreceptors. To explore retinal degeneration, we employed a multidisciplinary approach including live imaging using GFP tagged actin and arrestin 2. Importantly, we demonstrate that the major rhodopsin (Rh1) was greatly reduced before the onset of rhabdomere degeneration; a great reduction of Rh1 affects the maintenance of rhabdomere leading to degeneration of photoreceptors. TrpP365/+ also led to the up-regulation of CaMKII, which is beneficial as suppression of CaMKII accelerated retinal degeneration. We explored the regulation of TRP by investigating the genetic interaction between TrpP365/+ and mutants affecting the turnover of diacylglycerol (DAG). We show a loss of phospholipase C in norpAP24 exhibited a great reduction of the DAG content delayed degeneration of TrpP365/+ photoreceptors. In contrast, knockdown or mutations in DAG lipase (InaE) that is accompanied by slightly reduced levels of most DAG but an increased level of DAG 34:1, exacerbated retinal degeneration of TrpP365/+. Together, our findings support the notion that DAG plays a role in regulating TRP. Interestingly, DAG lipase is likely required during photoreceptor development as TrpP365/+; inaEN125 double mutants contained severely degenerated rhabdomeres

P23H opsin knock-in mice reveal a novel step in retinal rod disc morphogenesis

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Transcriptional response in the whiteleg shrimp (Penaeus vannamei) to short-term microplastic exposure

The ingestion of microplastics by diverse marine organisms induces behavioral disorders, physiological changes, and immune and stress responses. The negative effects of microplastic exposure in penaeid shrimps are still unclear despite the annual increase in the consumption of these food sources by humans and in marine aquaculture. Therefore, this study aimed to investigate the potential negative effects of microplastic exposure and gain a deeper understanding of its impacts on culturing penaeid shrimp. We generated RNA sequencing data from the whiteleg shrimp (Penaeus vannamei) artificially exposed to microplastics and analyzed the differentially expressed genes. Based on transcriptional comparisons, exposure to microplastics induces cardiac muscle dysfunction and promotes stress and immune responses in whiteleg shrimp. Thus, we confirmed the negative impact of microplastic exposure in whiteleg shrimp. These results provide a foundation for studies on the biological effects of microplastic ingestion on aquaculture species and their potential impact on humans through their consumption of these important marine resources