Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Pronounced and Extensive Microtubule Defects in a Saccharomyces cerevisiae DIS3 Mutant

ABSTRACT: The recently proposed exozyme hypothesis posits that subunits of the RNA processing exosome assemble into structurally distinct protein complexes that function in disparate cellular compartments and RNA metabolic pathways. Here, in a genetic test of this hypothesis, we examine the role of Dis3 -- an essential polypeptide with endo- and 3' to 5' exo-ribonuclease activity -- in cell cycle progression. We present several lines of evidence that perturbation of DIS3 affects microtubule (MT) localization and structure in Saccharomyces cerevisiae. Cells with a DIS3 mutation: (i) accumulate anaphase and pre-anaphase mitotic spindles; (ii) exhibit spindles that are mis-oriented and displaced from the bud neck; (iii) harbor elongated spindle-associated astral MTs; (iv) have an increased G1 astral MT length and number; and (v) are hypersensitive to MT poisons. Mutations in the core exosome genes RRP4 and MTR3 and the exosome cofactor gene MTR4 -- but not other exosome subunit gene mutants -- also elicit MT phenotypes. RNA deep sequencing analysis (RNA-seq) shows broad changes in the levels of cell cycle- and microtubule-related transcripts in mutant strains. Collectively, the different mitotic phenotypes and distinct sets of mRNAs affected by the exosome subunit and cofactor mutants studied here suggest that Dis3 has a core exosome-independent role(s) in cell cycle progression. These observations are consistent with the predictions of the exozyme hypothesis and also suggest an evolutionarily conserved role for Dis3 in linking RNA metabolism, MTs, and mitotic progression.

ORGANISM(S): Saccharomyces cerevisiae

PROVIDER: GSE29018 | GEO | 2013/01/01

SECONDARY ACCESSION(S): PRJNA140473

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Similar Datasets

Pronounced and Extensive Microtubule Defects in a Saccharomyces cerevisiae DIS3 Mutant

Project description:The recently proposed exozyme hypothesis posits that subunits of the RNA processing exosome assemble into structurally distinct protein complexes that function in disparate cellular compartments and RNA metabolic pathways. Here, in a genetic test of this hypothesis, we examine the role of Dis3 -- an essential polypeptide with endo- and 3' to 5' exo-ribonuclease activity -- in cell cycle progression. We present several lines of evidence that perturbation of DIS3 affects microtubule (MT) localization and structure in Saccharomyces cerevisiae. Cells with a DIS3 mutation: (i) accumulate anaphase and pre-anaphase mitotic spindles; (ii) exhibit spindles that are mis-oriented and displaced from the bud neck; (iii) harbor elongated spindle-associated astral MTs; (iv) have an increased G1 astral MT length and number; and (v) are hypersensitive to MT poisons. Mutations in the core exosome genes RRP4 and MTR3 and the exosome cofactor gene MTR4 -- but not other exosome subunit gene mutants -- also elicit MT phenotypes. RNA deep sequencing analysis (RNA-seq) shows broad changes in the levels of cell cycle- and microtubule-related transcripts in mutant strains. Collectively, the different mitotic phenotypes and distinct sets of mRNAs affected by the exosome subunit and cofactor mutants studied here suggest that Dis3 has a core exosome-independent role(s) in cell cycle progression. These observations are consistent with the predictions of the exozyme hypothesis and also suggest an evolutionarily conserved role for Dis3 in linking RNA metabolism, MTs, and mitotic progression. RNA-seq analysis of total RNA harvested from WT, mtr3-1, mtr4-1, and Dis3^mtr (rrp44-1/mtr17-1) Saccharomyces cerevisiae strains after a temperature shift.

2013-01-01 | E-GEOD-29018 | biostudies-arrayexpress

Structure of the native gamma-Tubulin Ring Complex capping spindle microtubules

Project description:Microtubules (MTs) are fundamental to cellular architecture, function and organismal development. They are nucleated from microtubule organizing centres by the evolutionary conserved ?-tubulin ring complex (?TuRC). However, the molecular mechanism of nucleation remains elusive. Here, we used cryo-electron tomography (cryo-ET) to determine the structure of the native ?TuRC capping the minus end of a MT in the context of enriched budding yeast spindles. In our structure, ?TuRC presents a ring of ?-tubulin subunits to seed nucleation of exclusively 13-protofilament microtubules, and it adopts an active closed conformation to function as a perfect geometric template for MT nucleation. Our cryo-ET reconstruction also revealed that a novel coiled-coil protein staples the first row of ?/?-tubulin molecules to alternating positions along the ?-tubulin ring. This positioning of ?/?-tubulin onto ?TuRC suggests a role for the coiled-coil protein in augmenting ?TuRC-mediated microtubule nucleation. Based on our results we describe a molecular model for budding yeast ?TuRC activation and MT nucleation.

2024-03-05 | PXD050372 | Pride

Phosphosites of the yeast centrosome component Spc110 contribute to mitotic exit

Project description:Spc110 is an essential component of the spindle pole body (SPB), the yeast equivalent of the centrosome, that recruits the gamma-tubulin complex to the nuclear side of SPB to form the mitotic spindle. Here we identify two phosphosites (S11 and S36) in old (from maternal origin) Spc110. Yeast expressing non-phosphorylatable Spc110S11AS36A were sensitive to the microtubule depolymerizing drug benomyl. In an undisturbed cell cycle, Spc110S11AS36A cells had normal spindles and cell cycle progression until late anaphase. However, Spc110S11AS36A cells were delayed in late-anaphase and presented elevated levels of Cdc14, a protein phosphatase required for mitotic exit, at the SPBs. Thus, we propose that the S11 and S36 phosphosites of Spc110 regulate Cdc14 localization at the SPBs for timely mitotic exit.

2023-04-03 | PXD033085 | JPOST Repository

Global analysis of the nuclear processing of unspliced U12-type introns by the exosome

Project description:we analyzed globally the effect of exosome processing on the nuclear pre-mRNA transcripts by inactivating either the RRP41 or DIS3 subunit of the exosome. Using SOLiD RNA sequencing technology, we report 30-120 million mapped cellular compartment specific reads per sample allowing the detection of unspliced pre-mRNAs. We show that RRP41 and DIS3 knockdowns stabilize an overlapping set of U12-type introns. Studying the global effect of the exosome (Rrp41 or Dis3 subunit) knockdown comparing to the control sample.

2014-05-26 | E-GEOD-52539 | biostudies-arrayexpress

Centrosomal ALIX regulates mitotic spindle orientation by modulating astral microtubule dynamics

Project description:The orientation of the mitotic spindle (MS) is tightly regulated, but the molecular mechanisms are incompletely understood. Here we report a novel role for the multifunctional adaptor protein ALG-2-interacting protein X (ALIX) in regulating MS orientation in addition to its well-established role in cytokinesis. We show that ALIX is recruited to the pericentriolar material (PCM) of the centrosomes and promotes correct orientation of the MS in asymmetrically dividing Drosophila stem cells and epithelial cells, and symmetrically dividing Drosophila and human epithelial cells. ALIX-deprived cells display defective formation of astral microtubules (MTs), which results in abnormal MS orientation. Specifically, ALIX is recruited to the PCM via Drosophila Spindle defective 2 (DSpd-2)/Cep192, where ALIX promotes accumulation of g-tubulin and thus facilitates efficient nucleation of astral MTs. In addition, ALIX promotes MT stability by recruiting Microtubule Associated Protein 1S (MAP1S), which stabilizes newly formed MTs. Altogether, our results demonstrate a novel evolutionarily conserved role of ALIX in providing robustness to the orientation of the MS by promoting astral MT formation during asymmetric and symmetric cell division.

2018-06-04 | PXD009747 | Pride

Inactivation of the exosome ribonuclease DIS3 triggers the pluripotency factor LIN28B, repressing let-7 miRNAs and unleashing MYC and RAS.

2015-06-12 | GSE55246 | GEO

Inactivation of the exosome ribonuclease DIS3 triggers the pluripotency factor LIN28B, repressing let-7 miRNAs and unleashing MYC and RAS.

Project description:Somatic mutations affecting DIS3, the catalytic component of the RNA exosome, have been found in up to 18% of patients affected by the hematological cancer multiple myeloma. Here we show that DIS3 targets and degrades the pluripotency factor LIN28B. In cancer cells, DIS3 inactivation leads to enhanced LIN28B expression, thus disrupting the let-7 miRNAs tumor suppressor network and ultimately increasing protein levels of crucial oncogenes such as MYC and RAS. DIS3 represents the catalytic component of the exosome. The exosome is required for cell viability and targets several RNA species, including pre-mRNAs, pre-tRNAs, pre-rRNAs, snRNAs and snoRNAs. To gain insight on the macular wiring underlying DIS3 activity in mammalian cells, we comprehensively evaluated expression profiles, including miRNAs, in various cell lines, upon DIS3 knockdown. This series of microarray experiments contains the miRNA expression profiles of independent replicates of RPMI-8226, KMS12-BM multiple myeloma cell lines and HEK-293T cells, knocked-down with a scrambled or hDIS3 sh4 and collected 72 hours after infection. 500 nanograms of total RNA were processed using the FlashTag labeling kit, which uses a tailing reaction followed by ligation of the biotinylated signal molecule to the target RNA sample. The labelled RNA was then hybridized to Affymetrix GeneChip® microRNA arrays v1.0, following the Affymetrix manufacturer's instructions.

2015-06-12 | E-GEOD-55246 | biostudies-arrayexpress

Expression analysis of pre-phenotype dt27J mouse dorsal root ganglia

Project description:Loss of function of dystonin cytoskeletal linker proteins causes neurodegeneration in the sensory ataxia, dystonia musculorum (dt). While much investigation has focused on understanding dt pathology, divergent functions of dystonin isoforms are still unknown. Here, we highlight a novel function of the dystonin-a2 isoform in mediating microtubule (MT) stability, golgi organization and flux through the secretory pathway. Using dystonin-null mice combined with isoform-specific loss of function analysis, we find dystonin-a2 is bound to MAP1B in the area surrounding the centrosome, where it maintains MT acetylation. In dt, the absence of the MAP1B-dystonin-A2 interaction results in a loss of MAP1B perinuclear localization, leading to MT deacetylation and instability. Deacetylated MTs lead to golgi fragmentation and prevent anterograde trafficking of motor proteins. Maintenance of MT acetylation through TSA administration or MAP1B overexperssion in vitro, mitigates the observed defect. These aberrations are apparent in pre-phenotype dorsal root ganglia (DRG) and primary sensory neurons, suggesting they are causal in the dt disorder.

2012-02-23 | GSE30960 | GEO

Expression analysis of pre-phenotype dt27J mouse dorsal root ganglia

2012-02-23 | E-GEOD-30960 | biostudies-arrayexpress

Global analysis of the nuclear processing of unspliced U12-type introns by the exosome

2014-05-26 | GSE52539 | GEO