Project description:Innate immunity, the first line of host defense against pathogens, is tightly regulated both transcriptionally and post-transcriptionally. Here, through global transcriptome and proteome analyses in Caenorhabditis elegans, we uncover a modulation of the expression of secreted innate immunity effector proteins by TENT5, one of a recently described family of cytoplasmic poly(A) polymerases. Direct RNA sequencing revealed that TENT-5 polyadenylates mRNAs with signal peptide-encoding sequences, that are translated at the endoplasmic reticulum. Loss of tent-5 function makes worms more susceptible to bacterial infection. Importantly, we demonstrate that the function of TENT-5 in innate immunity is evolutionarily conserved, as its orthologs, TENT5A and TENT5C are induced during macrophage activation and polyadenylate mRNAs, some of which are of genes orthologous to C. elegans TENT-5 targets. In summary, our study reveals cytoplasmic polyadenylation to be a previously unknown component of the post-transcriptional regulation of innate immunity in animals.
Project description:FAM46C is one of the most frequently mutated genes in multiple myeloma (MM) and encodes a protein of unknown function. Using a combination of in vitro and in vivo approaches, we demonstrate that FAM46C encodes an active cytoplasmic non-canonical poly(A) polymerase, which enhances mRNA stability and gene expression. Moreover, we also found that the reintroduction of active FAM46C into MM cell lines, but not its catalytically-inactive mutant, leads to broad polyadenylation and stabilization of mRNAs strongly enriched with those encoding endoplasmic reticulum-targeted proteins and induced cell death. This is, to our knowledge, the first report that directly associates cytoplasmic poly(A) polymerase with carcinogenesis. Furthermore, our data suggest that the human genome encodes at least eleven non-canonical poly(A) polymerases with four FAM46 family members. Since FAM46 proteins are differentially expressed during development, these proteins may positively regulate transcript stability and translational rate in a tissue-specific manner.
Project description:Innate immunity, the first line of host defense against pathogens, is tightly regulated both transcriptionally and post-transcriptionally. Through global transcriptome and proteome analyses in Caenorhabditis elegans, we uncover a modulation of the expression of secreted innate immunity effector proteins by TENT5, one of a recently described family of cytoplasmic poly(A) polymerases. Direct RNA sequencing revealed that TENT-5 polyadenylates mRNAs with signal peptide-encoding sequences, that are translated at the endoplasmic reticulum. Loss of tent-5 function makes worms more susceptible to bacterial infection. Importantly, we demonstrate that the function of TENT-5 in innate immunity is evolutionarily conserved, as its orthologs, TENT5A and TENT5C are induced during macrophage activation and polyadenylate mRNAs, some of which are of genes orthologous to C. elegans TENT-5 targets. In summary, our study reveals cytoplasmic polyadenylation to be a previously unknown component of the post-transcriptional regulation of innate immunity in animals.
Project description:Comparision of mRNA abundance and translation efficiency mediated by cytoplasmic poly(A) polymerases in C. elegans comparision of different adults treated with RNAi
Project description:In animals with germ plasm, specification of the germline involves “germ granules”, cytoplasmic condensates that enrich maternal transcripts in the germline founder cells. In C. elegans embryos, P granules enrich maternal transcripts, but surprisingly P granules are not essential for germ cell fate specification. Here we have described a second condensate in the C. elegans germ plasm. Like canonical P-bodies found in somatic cells, “germline P-bodies” contain regulators of mRNA decapping and deadenylation and, in addition, the intrinsically-disordered proteins MEG-1 and MEG-2 and the TIS11-family RNA-binding protein POS-1. Embryos lacking meg-1 and meg-2 do not stabilize P-body components, miss-regulate POS-1 targets, miss-specify the germline founder cell, and do not develop a germline. Our findings suggest that specification of the germ line involves at least two distinct condensates that independently enrich and regulate maternal mRNAs in the germline founder cells.
Project description:In animals with germ plasm, specification of the germline involves “germ granules”, cytoplasmic condensates that enrich maternal transcripts in the germline founder cells. In C. elegans embryos, P granules enrich maternal transcripts, but surprisingly P granules are not essential for germ cell fate specification. Here we describe a second condensate in the C. elegans germ plasm. Like canonical P-bodies found in somatic cells, “germline P-bodies” contain regulators of mRNA decapping and deadenylation and, in addition, the intrinsically-disordered proteins MEG-1 and MEG-2 and the TIS11-family RNA-binding protein POS-1. Embryos lacking meg-1 and meg-2 do not stabilize P-body components, miss-regulate POS-1 targets, miss-specify the germline founder cell, and do not develop a germline. Our findings suggest that specification of the germ line involves at least two distinct condensates that independently enrich and regulate maternal mRNAs in the germline founder cells.
Project description:The GLD-2 class of poly(A) polymerases regulate the timing of translation of stored transcripts by elongating the poly(A) tails of target mRNAs in the cytoplasm. WISPY is a GLD-2 enzyme that acts in the Drosophila female germline and is required for the completion of the egg-to-embryo transition. Though a handful of WISPY target mRNAs have been identified during both oogenesis and early embryogenesis, we aimed to discover the full range of WISPY targets at each stage. To globally identify these targets, we carried out microarray analysis to look for maternal mRNAs whose poly(A) tails fail to elongate in the absence of WISP function. We examined the polyadenylated portion of the maternal transcriptome in both stage 14 (mature) oocytes and in early embryos that had completed egg activation. Our analysis shows that the poly(A) tails of thousands of maternal mRNAs fail to elongate in wisp-deficient oocytes and embryos. Furthermore, we have identified specific classes of genes that are highly regulated in this manner at each stage. Our study shows that cytoplasmic polyadenylation is a major regulatory mechanism during oocyte maturation and egg activation. Four groups of comparisons: WT vs. wisp total RNA from stage 14 oocytes, WT vs. wisp total RNA from fertilized eggs, WT vs. wisp poly(A)+ RNA from stage 14 oocytes, WT vs. wisp poly(A)+ RNA from fertilized eggs. Each comparison consisted of three independent RNA extractions and each experiment was done with dye-swap pairs as two technical replicates.
Project description:We report changes in total and translated poly(A) RNA in mouse bone marrow derived macrophages after exposure to hypoxia. We employed translating ribosome affinity purification (TRAP) to isolate polysomal RNA from mouse bone marrow derived macrophages after exposure to hypoxia