Project description:The goal of this study was to determine transcriptional changes in HEK293 cells upon overexpression of various forms of Paternally Expressed Gene 10, or PEG10. Cells were transfected either with control, or with PEG10 gag, gag-pol, or isolated NC fragment constructs and RNA isolated for RNA-Seq analysis.
Project description:The prevailing dogma that approximately 50% of our genome is “junk” DNA composed of transposable elements and retroviral insertions has recently been challenged. It has become evident that our genome has taken advantage of these transposable elements and uses them as a source of DNA to generate novel genes, which subsequently allow the organism to evolve. This process is termed “domestication of transposable elements” and the majority of these genes have been found to be essential for the existence of the organism. One of these developmentally essential domesticated genes: Peg10 (paternally expressed gene 10), was derived from a Ty3/gyspy LTR retrotransposon, yet lost its ability to transpose due to mutational events during its domestication. Remarkably, Peg10 has successfully maintained its Gag and Pol-like domains for millions of years. Peg10 orthologues are expressed in eutherian mammals and are essential for placentogenesis. To address the functional mechanisms of Peg10 we studied it in Trophoblast Stem Cells (TSCs). We find that the Gag of Peg10 is fully active: it promotes budding of vesicles, akin to the viral counterpart that catalyzes the budding of viruses. TSCs, deleted for Peg10, fail to differentiate into placental lineages, underscoring a critical role in lineage specification. This paper discusses our efforts to characterize the contents of Peg10 vesicles and whether such vesicles regulate lineage specification.
Project description:Amyotrophic Lateral Sclerosis (ALS) is a rare neurodegenerative disease characterized by motor neuron dysfunction and loss, leading to progressive paralysis and death. A portion of ALS cases is caused by mutation of the proteasome shuttle factor Ubiquilin 2 (UBQLN2), but the molecular pathway leading from UBQLN2 dysfunction to neurodegenerative disease remains unclear. Here, we demonstrate a major function of UBQLN2 in regulating activity of the domesticated gag-pol retrotransposon ‘paternally expressed gene 10’ (PEG10) in human cells and tissues. UBQLN2 exclusively facilitates degradation of the frameshifted gag-pol form of PEG10 through recognition of a unique polyproline repeat. In cells, the PEG10 gag-pol protein cleaves itself in a mechanism reminiscent of retrotransposon self-processing to generate a liberated ‘nucleocapsid’ fragment, which uniquely localizes to the nucleus. Overexpression of the nucleocapsid fragment upregulates transcription of neuronal genes involved in axon remodeling, which were also affected in sporadic ALS (sALS) patient tissues. Finally, proteomics of spinal cords from ALS patients revealed that PEG10 gag-pol is significantly elevated in disease compared to healthy controls. These findings implicate the retrotransposon-like activity of PEG10 as a contributing mechanism in ALS through regulation of neuronal gene expression, and restraint of PEG10 as a primary function of UBQLN2.
Project description:The prevailing dogma that approximately 50% of our genome is “junk” DNA composed of transposable elements and retroviral insertions has recently been challenged. It has become evident that our genome has taken advantage of these transposable elements and uses them as a source of DNA to generate novel genes, which subsequently allow the organism to evolve. This process is termed “domestication of transposable elements” and the majority of these genes have been found to be essential for the existence of the organism. One of these developmentally essential domesticated genes: Peg10 (paternally expressed gene 10), was derived from a Ty3/gyspy LTR retrotransposon, yet lost its ability to transpose due to mutational events during its domestication. Remarkably, Peg10 has successfully maintained its Gag and Pol-like domains for millions of years. Peg10 orthologues are expressed in eutherian mammals and are essential for placentogenesis. To address the functional mechanisms of Peg10 we studied it in Trophoblast Stem Cells (TSCs). We find that the Gag of Peg10 is fully active: it promotes budding of vesicles, akin to the viral counterpart that catalyzes the budding of viruses. TSCs, deleted for Peg10, fail to differentiate into placental lineages, underscoring a critical role in lineage specification. This paper discusses our efforts to characterize the contents of Peg10 vesicles and whether such vesicles regulate lineage specification.
Project description:To gain insight into the function of Nuclear pore associated protein 1 (NPAP1, formerly C15orf2), we overexpressed NPAP1 in HEK293 cells. We detected no significant difference between NPAP1-expression of induced and uninduced cells in three technical replicates, exept for an approximately 10-fold increase in the NPAP1 transcript itself. This indicates that overexpression of NPAP1 does not change mRNA expression profiles of HEK293 cells. We used microarrays to investigate global gene expression changes depending on the level of NPAP1/C15orf2 We compared NPAP1 overexpressing cells to untreated cells, which do not express detectable amounts of NPAP1 protein, to determine global gene expression changes.
Project description:To gain insight into the function of Nuclear pore associated protein 1 (NPAP1, formerly C15orf2), we overexpressed NPAP1 in HEK293 cells. We detected no significant difference between NPAP1-expression of induced and uninduced cells in three technical replicates, exept for an approximately 10-fold increase in the NPAP1 transcript itself. This indicates that overexpression of NPAP1 does not change mRNA expression profiles of HEK293 cells. We used microarrays to investigate global gene expression changes depending on the level of NPAP1/C15orf2
Project description:Mycosis fungoides (MF), the most common subtype of cutaneous T-cell lymphoma (CTCL), may undergo large-cell transformation (LCT), which is related to aggressive clinical courses and resistance to conventional treatments. However, the mechanisms of LCT remain largely unknown.We performed RNA-seq on biopsied specimens isolated from 26 MF-LCT patients and 23 MF-NLCT patients to decipher the mechanisms underlying LCT. We found PEG10 was overexpressed in MF-LCT compared with MF -NLCT cases. In order to explore the function of PEG10 in the pathogenesis of MF, transcriptome sequencing was performed among HH cells transfected with shRNAs targeting PEG10 (shPEG10) and scrambled shRNA(sh0) , Myla cells transfected with empty vetors(vec) and PEG10 expression vectors ( RF1b, RF1b/2, RF1b/2+CNF) to investigate genes regulated by PEG10 in CTCL cells .
Project description:Neuroendocrine prostate cancer (NEPC) is proliferative, invasive, and untreatable. Its molecular pathogenesis remains poorly understood but appears to require TP53 and RB1 aberration. In this study we modeled the development of NEPC from conventional prostatic adenocarcinoma using a unique patient-derived xenograft and identified up-regulation of the placental gene PEG10. We found that the androgen receptor and the E2F/RB pathway dynamically regulate distinct post-transcriptional and post-translational isoforms of PEG10 at different stages of NEPC development. In vitro, PEG10 promoted cell cycle progression from G0/G1 in the context of TP53 loss, and regulated Snail expression via TGF-β signaling to promote invasion. Finally we show in vivo proof of principal using antisense oligonucleotide that PEG10 is a novel therapeutic target for NEPC.