Organismal functionality and reproduction depend on metabolic rewiring and balanced energy resources. However, the crosstalk between organismal homeostasis and fecundity and the associated paracrine signaling mechanisms are still poorly understood. Using Caenorhabditis elegans, we discovered that large extracellular vesicles (known as exophers) previously found to remove damaged subcellular elements in neurons and cardiomyocytes are released by body wall muscles (BWM) to support embryonic growth. Exopher formation (exopheresis) by BWM is sex‐specific and a non‐cell autonomous process regulated by developing embryos in the uterus. Embryo‐derived factors induce the production of exophers that transport yolk proteins produced in the BWM and ultimately deliver them to newly formed oocytes. Consequently, offspring of mothers with a high number of muscle‐derived exophers grew faster. We propose that the primary role of muscular exopheresis is to stimulate reproductive capacity, thereby influencing the adaptation of worm populations to the current environmental conditions.

CRNDE, recently described as the lncRNA-coding gene, is overexpressed at RNA level in human malignancies. Its role in gametogenesis, cellular differentiation and pluripotency has been suggested as well. Herein, we aimed to verify our hypothesis that the CRNDE gene may encode a protein product, CRNDEP. By using bioinformatics methods, we identified the 84-amino acid ORF encoded by one of two CRNDE transcripts, previously described by our research team. This ORF was cloned into two expression vectors, subsequently utilized in localization studies in HeLa cells. We also developed a polyclonal antibody against CRNDEP. Its specificity was confirmed in immunohistochemical, cellular localization, Western blot and immunoprecipitation experiments, as well as by showing a statistically significant decrease of endogenous CRNDEP expression in the cells with transient shRNA-mediated knockdown of CRNDE. Endogenous CRNDEP localizes predominantly to the nucleus and its expression seems to be elevated in highly proliferating tissues, like the parabasal layer of the squamous epithelium, intestinal crypts or spermatocytes. After its artificial overexpression in HeLa cells, in a fusion with either the EGFP or DsRed Monomer fluorescent tag, CRNDEP seems to stimulate the formation of stress granules and localize to them. Although the exact role of CRNDEP is unknown, our preliminary results suggest that it may be involved in the regulation of the cell proliferation. Possibly, CRNDEP also participates in oxygen metabolism, considering our in silico results, and the correlation between its enforced overexpression and the formation of stress granules. This is the first report showing the existence of a peptide encoded by the CRNDE gene.

Running title: mdx mutation affects calcium signalling in myoblastsHighlights:1. NGS reveals changes in Ca 2+ signalling-related RNAs in mdx myoblasts 2. Mdx myoblasts exerts increased susceptibility to P2RY2-mediated stimulation 3. Levels of several Ca 2+ signalling-related proteins are changed in mdx myoblasts 4. P2RY2 agonist slows-down mdx myoblasts motility SummaryPathophysiology of Duchenne Muscular Dystrophy is still elusive. Although progressive damage to muscle fibres is a cause of muscle deterioration leading to premature death, there is a growing body of evidence indicating that the triggering effects of DMD mutation are present at the very early stage of muscle development. Previously, elevated activity of P2X7 receptors and increased store-operated calcium entry were shown in myoblasts derived from mdx mice. Here, the metabotropic extracellular ATP/UTP-evoked response has been investigated. Sensitivity to antagonist, effect of gene silencing and cellular localization studies showed that elevated purinergic responses in mdx myoblasts have been caused by increased expression of P2Y2 but not P2Y4 receptors. These alterations have physiological implications as shown by reduced motility of mdx myoblasts upon treatment with P2Y2 agonist. The ultimate increase in intracellular calcium in dystrophic cells reflected complex alterations of calcium homeostasis identified in the RNA seq data and with significant modulation at the protein level including a decrease of Gq11 subunit , PMCA, IP3-receptor and elevation of PLC, SERCA and NCX. In conclusion, whereas specificity of dystrophic myoblast excitation by extracellular ATP is determined by specific receptor overexpression, the intensity of this altered response depends on relative activities of downstream calcium regulators that also accompany the Dmd gene mutation. These results confirm that phenotypic effects of DMD emerge in undifferentiated muscle cells and not only due to the absence of dystrophin protein in myofibres. Therefore, the pathogenesis of DMD and the relevance of current therapeutic approaches may need re-evaluation.