Project description:Gene silencing mediated by dsRNA (RNAi) can persist for multiple generations in C. elegans (termed RNAi inheritance). Here we describe the results of a forward genetic screen in C. elegans that has identified six factors required for RNAi inheritance: GLH-1/VASA, PUP-1/CDE-1, MORC-1, SET-32, and two novel nematode-specific factors that we term here (heritable RNAi defective) HRDE-2 and HRDE-4. The new RNAi inheritance factors exhibit mortal germline (Mrt) phenotypes, which we show is likely caused by epigenetic deregulation in germ cells. We also show that HRDE-2 contributes to RNAi inheritance by facilitating the binding of small RNAs to the inheritance Argonaute (Ago) HRDE-1. Together, our results identify additional components of the RNAi inheritance machinery whose sequence conservation provides insights into the molecular mechanism of RNAi inheritance, further our understanding of how the RNAi inheritance machinery promotes germline immortality, and show that HRDE-2 couples the inheritance Ago HRDE-1 with the small RNAs it needs to direct RNAi inheritance and germline immortality.
Project description:Dysfunction of the motor subunit of the TIM23 translocase, the PAM complex located on the matrix side of the mitochondrial inner membrane in Saccharomyces cerevisiae, was shown to cause a decrease in mitochondrial protein import and precursor accumulation in the cytosol. We used an analogous model to study the non-mitochondrial response to defective mitochondrial import machinery in Caenorhabditis elegans in which we depleted DNJ-21 as the functional homolog of yeast Pam18. To gain a broader insight in potential changes in Caenorhabditis elegans proteome upon DNJ-21 depletion we performed a quantitative, label-free proteomics analysis. We compared protein levels upon knockdown of dnj-21 (dnj-21 RNAi) with control conditions (Empty vector RNAi). Synchronized N2 wild type worms were grown on NGM plates seeded with E. coli HT115(DE3) transformed with a construct targeting dnj-21 gene or with empty vector L4440 as a control.
Project description:we used Caenorhabditis elegans as a model organism, to investigate the effect of mannose on the lifespan. Using nematode RNAi methods, RT-PCR, RNA-seq and other experimental method, we explored the possible mechanism for how mannose change the lifespan of Caenorhabditis elegans.
Project description:The nematode Caenorhabditis elegans has evolutionarily conserved EV signaling pathways. In this study, we apply a recently published method for high specificity purification of EVs from C. elegans to carry out target-independent proteomic and RNA analysis of EVs from C. elegans. Our experiments uncovered diverse coding and non-coding RNA transcripts as well as protein cargo types commonly found in human EVs.
