Similar Datasets
Project description:Unlike in metazoans, the stepwise biogenesis of microRNAs (miRNAs) in plants occurs within the nucleus. Whether or how the major steps in miRNA biogenesis are coordinated is largely unknown. Here we show that the plant TREX-2 complex promotes multiple steps in miRNA biogenesis, including transcription, processing and nuclear export. THP1 and SAC3A-the core subunits of TREX-2-interact and colocalize with RNA polymerase II to promote the transcription of MIR genes in the nucleoplasm. TREX-2 interacts with the microprocessor component SERRATE and promotes the formation of dicing bodies in the nucleoplasm. THP1 also interacts and colocalizes with the nucleoporin protein NUP1 at the nuclear envelope. NUP1 and THP1 promote the nuclear export of miRNAs and ARGONAUTE1. These results suggest that TREX-2 coordinates the transcription, processing and export steps in miRNA biogenesis to ensure efficient miRNA production.
| S-EPMC7426256 | biostudies-literature
Project description:Unlike in metazoans, the stepwise biogenesis of microRNAs (miRNAs) occurs within the nucleus in plants. Whether or how the major steps in miRNA biogenesis are coordinated is largely unknown. Here, we show that the plant TREX-2 complex promotes multiple steps in miRNA biogenesis, including transcription, processing and nuclear export. Core subunits of TREX-2, THP1 and SAC3A, interact and co-localize with RNA Polymerase II to promote the transcription of MIR genes in the nucleoplasm. TREX-2 interacts with the microprocessor component SERRATE and promotes the formation of Dicing bodies in the nucleoplasm. THP1 also interacts and co-localizes with a nucleoporin protein NUP1 at the nuclear envelope. NUP1 and THP1 promote the nuclear export of miRNAs and AGO1. These results suggest that TREX-2 coordinates the transcription, processing and export steps in miRNA biogenesis to ensure efficient miRNA production.
2020-08-07 | GSE150472 | GEO
Project description:Unlike in metazoans, the stepwise biogenesis of microRNAs (miRNAs) occurs within the nucleus in plants. Whether or how the major steps in miRNA biogenesis are coordinated is largely unknown. Here, we show that the plant TREX-2 complex promotes multiple steps in miRNA biogenesis, including transcription, processing and nuclear export. Core subunits of TREX-2, THP1 and SAC3A, interact and co-localize with RNA Polymerase II to promote the transcription of MIR genes in the nucleoplasm. TREX-2 interacts with the microprocessor component SERRATE and promotes the formation of Dicing bodies in the nucleoplasm. THP1 also interacts and co-localizes with a nucleoporin protein NUP1 at the nuclear envelope. NUP1 and THP1 promote the nuclear export of miRNAs and AGO1. These results suggest that TREX-2 coordinates the transcription, processing and export steps in miRNA biogenesis to ensure efficient miRNA production.
2020-08-07 | GSE150471 | GEO
Project description:Linking Key Steps of MicroRNA Biogenesis by TREX-2 and the Nuclear Pore Complex in Arabidopsis
| PRJNA632504 | ENA
Project description:Linking Key Steps of MicroRNA Biogenesis by TREX-2 and the Nuclear Pore Complex in Arabidopsis [mRNA-Seq]
| PRJNA632509 | ENA
Project description:Linking Key Steps of MicroRNA Biogenesis by TREX-2 and the Nuclear Pore Complex in Arabidopsis [miRNA-Seq]
| PRJNA632508 | ENA
Project description:Nuclear pore complexes (NPCs) influence gene expression besides their established function in nuclear transport. The TREX-2 complex localizes to the NPC basket and affects gene-NPC interactions, transcription, and mRNA export. How TREX-2 regulates the gene expression machinery is unknown. Here, we show that TREX-2 interacts with the Mediator complex, an essential regulator of RNA Polymerase (Pol) II. Structural and biochemical studies identify a conserved region on TREX-2, which directly binds the Mediator Med31/Med7N submodule. TREX-2 regulates assembly of Mediator with the Cdk8 kinase and is required for recruitment and site-specific phosphorylation of Pol II. Transcriptome and phenotypic profiling confirm that TREX-2 and Med31 are functionally interdependent at specific genes. TREX-2 additionally uses its Mediator-interacting surface to regulate mRNA export suggesting a mechanism for coupling transcription initiation and early steps of mRNA processing. Our data provide mechanistic insight into how an NPC-associated adaptor complex accesses the core transcription machinery.
| S-EPMC4644235 | biostudies-literature
Project description:Nuclear pore complexes (NPCs) are large proteinaceous assemblies that mediate nuclear compartmentalization. NPCs undergo large-scale structural rearrangements during mitosis in metazoans and some fungi. However, our understanding of NPC remodeling beyond mitosis remains limited. Using time-lapse fluorescence microscopy, we discovered that NPCs undergo two mechanistically separable remodeling events during budding yeast meiosis in which parts or all of the nuclear basket transiently dissociate from the NPC core during meiosis I and II, respectively. Meiosis I detachment, observed for Nup60 and Nup2, is driven by Polo kinase-mediated phosphorylation of Nup60 at its interface with the Y-complex. Subsequent reattachment of Nup60-Nup2 to the NPC core is facilitated by a lipid-binding amphipathic helix in Nup60. Preventing Nup60-Nup2 reattachment causes misorganization of the entire nuclear basket in gametes. Strikingly, meiotic nuclear basket remodeling also occurs in the distantly related fission yeast, Schizosaccharomyces pombe. Our study reveals a conserved and developmentally programmed aspect of NPC plasticity, providing key mechanistic insights into the nuclear basket organization.
| S-EPMC9754704 | biostudies-literature
Project description:The nuclear envelope (NE) assembles and grows from bilayer lipids produced at the endoplasmic reticulum (ER). How ER membrane incorporation coordinates with assembly of nuclear pore complexes (NPCs) to generate a functional NE is not well understood. Here, we use the stereotypical first division of the early C. elegans embryo to test the role of the membrane-associated nucleoporin Ndc1 in coupling NPC assembly to NE formation and growth. 3D-EM tomography of reforming and expanded NEs establishes that Ndc1 determines NPC density. Loss of ndc1 results in faster turnover of the outer scaffold nucleoporin Nup160 at the NE, providing an explanation for how Ndc1 controls NPC number. NE formation fails in the absence of both Ndc1 and the inner ring component Nup53, suggesting partially redundant roles in NPC assembly. Importantly, upregulation of membrane synthesis restored the slow rate of nuclear growth resulting from loss of ndc1 but not from loss of nup53. Thus, membrane biogenesis can be decoupled from Ndc1-mediated NPC assembly to promote nuclear growth. Together, our data suggest that Ndc1 functions in parallel with Nup53 and membrane biogenesis to control NPC density and nuclear size.
| S-EPMC9296133 | biostudies-literature
Project description:MicroRNAs (miRNAs) are important for regulating gene expression in muticellular organisms. MiRNA processing is a two-step process. In animal cells, the first step is nuclear and the second step cytoplasmic, whereas in plant cells, both steps occur in the nucleus via the enzyme Dicer-like1 (DCL1) and other proteins including the zinc-finger-domain protein Serrate (SE) and a double-stranded RNA (dsRNA) binding-domain protein, Hyponastic Leaves1 (HYL1). Furthermore, plant miRNAs are methylated by Hua Enhancer (HEN1) at their 3' ends and loaded onto Argonaute1 (AGO1). However, little is known about the cellular basis of miRNA biogenesis. Using live-cell imaging, we show here that DCL1 and HYL1 colocalize in discrete nuclear bodies in addition to being present in a low-level diffuse nucleoplasmic distribution. These bodies, which we refer to as nuclear dicing bodies (D-bodies), differ from Cajal bodies. A mutated DCL1 with impaired function in miRNA processing fails to target to D-bodies, and an introduced primary (pri)-miRNA transcript is recruited to D-bodies. Furthermore, bimolecular fluorescence complementation (BiFC) shows that DCL1, HYL1, and SE interact in D-bodies. On the basis of these data, we propose that D-bodies are crucial for orchestrating pri-miRNA processing and/or storage/assembly of miRNA-processing complexes in the nuclei of plant cells.
| S-EPMC1950788 | biostudies-literature