Angus I Lamond

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..This review summarizes recent progress in understanding nuclear organization, highlighting in particular the dynamic aspects of nuclear structure...

..Studies on the composition, structure and behaviour of speckles have provided a model for understanding the functional compartmentalization of the nucleus and the organization of the gene-expression machinery...

..This in vivo study indicates that SMN and coilin interact differentially with Cajal bodies and reveals parallels in the pathway for reassembly of nucleoli and Cajal bodies following mitosis...

..hnRNP-M affects both 5' and 3' alternative splice site choices, and an hnRNP-M mutant lacking the CDC5L/PLRG1 interaction domain is unable to modulate alternative splicing of an adeno-E1A mini-gene substrate...

..The data show that FRET studies offer a valuable approach for probing interactions between pre-mRNA splicing factors in vivo...

..5K proteins appear not to be SUMO targets. SUMOylation is essential for high-affinity Nop58 binding to snoRNAs. This study provides direct evidence linking SUMO modification with snoRNP function...

..hSpagh also bound the free RPA194 subunit of RNA polymerase I, suggesting a general role in assembling RNA polymerases...

..We foresee applications for snoMEN vectors in basic gene expression research, target validation, and gene therapy...

..SART1 and heterogeneous nuclear RNP M were both shown to be genuine SUMO targets, confirming the validity of the approach...

..This strongly correlated with subunits of large, multiprotein complexes, suggesting a general mechanism whereby their assembly is controlled in a different subcellular location to their main site of function...

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..Thus paraspeckles are the sites where a subset of the total cellular pool of p54nrb is targeted in a RNA Polymerase II-dependent manner...

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..These data highlight an important new arm of the NEDD8-cullin pathway...

..Collectively, these experimental and analytical approaches provide a framework for expanding the functional annotation of the genome...

..Spatial mapping using FLIM-FRET reveals differences in splicing factors interactions within complexes located in separate subnuclear domains...

..The data show a specific temporal pathway involving the sequential and directed accumulation of NHPX in distinct subnuclear compartments, and define a novel mechanism for nucleolar localization...

..The data indicate that Repo-Man forms an essential complex with PP1gamma and is required for the recruitment of PP1 to chromatin...

..Here, we review the impact of new technologies, especially in areas of fluorescence microscopy and proteomics, which are providing major insights into dynamic processes affecting both structure and function within the nucleus...

..Expression of GFP-R2-PPP4c in HeLa cells enhances the temporal localisation of newly formed snRNPs, which is consistent with an association of R2-PPP4c with the SMN protein complex...

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..The data suggest that a subset of small regulatory RNAs may have evolved from box C/D snoRNAs...

..These data demonstrate that CBs are specific nuclear targets of cellular stress-response pathways and identify PA28gamma as a novel regulator of CB integrity...

..g. LocusLink, OMIM and PubMed)...

..INBs are abundant in nucleoli of unstressed cells during S phase and localise in close proximity to rDNA with heterochromatic features. The data suggest the INB is linked with regulation of rDNA transcription and/or maintenance of rDNA...

..The results from this study indicate that the interaction between CDC5L and PLRG1 is essential for pre-mRNA splicing and further demonstrate that small peptides can be used as effective splicing inhibitors...

..This review focuses on nucleolar dynamics, studied at each of the single protein, collective proteome, and subnucleolar organization levels...

..The detection of small RNA molecules that share features of miRNAs and snoRNAs suggest that these classes of RNA may have an evolutionary relationship...

..DNA damage was found to cause dissociation of the proteasome from inhibitory proteins and assembly chaperones in the cytoplasm and relocation to associate with proteasome activators in the nucleus...

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..The changing spatio-temporal distribution of PP1gamma revealed using the stable PP1 cell lines implicates it in multiple processes, including nucleolar function, the regulation of chromosome segregation and cytokinesis...

..NoLSs are a prevalent type of targeting motif that is distinct from nuclear localization signals and that can be computationally predicted...

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..A detailed protocol describing the complete microscope procedure and the choice of the appropriate experimental controls as well as the FRET calculations is also included...

..In several cases, as highlighted here, this has turned up surprising results and has forced a re-evaluation of models for nuclear structure and gene regulation...

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..Functional analyses demonstrated that this region of HBII-180C can influence the alternative splicing of FGFR3 pre-mRNA, supporting a role for some snoRNAs in the regulation of splicing...

..Many nuclear proteins are known to interact dynamically with one or other of these bodies, and disruption of the specific organization of nuclear proteins can result in defects in cell functions and may cause molecular disease...

..However, in most cases, we know neither the fraction of each protein pool that is nucleolus-associated nor whether their association is permanent or conditional...

..These data are consistent with extensive higher order folding of chromatin fibers taking place during anaphase...

..Detailed experimental methodologies have been referenced but not described in the form of protocols...

..Crosstalk between nucleoli and CBs is also discussed in the context of stress responses...

..Unexpectedly, both the direct DNA sequencing and fluorescence photoactivation data show that certain chromatin loci can specifically associate with either the nucleolus, or the nuclear envelope...

..This behaviour is fundamentally different from the ATP-dependent mobility observed for chromatin and suggests that a novel mechanism governs CB, and possibly other, nuclear body dynamics...

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..These exciting advances show that protein phosphatases are not merely silent partners to kinases in regulating the control of cell division...

..The inhibition of splicing in tsBN67 cells correlates with the temperature-sensitive cell cycle arrest phenotype, suggesting that HCF-1-dependent splicing events may be required for cell cycle progression...

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..Combining our approach with quantitative proteomics methods, we characterized the heat-shock response in worms...

..Bioinformatic analysis of the entire data set is presented in the Encyclopedia of Proteome Dynamics, a web-based resource, with proteins annotated for stability and subcellular distribution...

..The Cajal body is an example of a conserved nuclear compartment that has been linked to molecular disease. Recent studies have shown Cajal bodies to be surprisingly mobile and offer clues about their function in the cell...

..FMN2 is also induced by activation of other oncogenes, hypoxia, and DNA damage. These results identify FMN2 as a crucial component in the regulation of p21 and consequent oncogene/stress-induced cell-cycle arrest in human cells...

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..Furthermore, we show that the two enzymes function nonredundantly in Sm protein methylation. Lastly, we provide in vivo evidence demonstrating that Sm protein sDMA modification is required for snRNP biogenesis in human cells...

..The data also show that the protein composition of nucleoli is not static and can alter significantly in response to the metabolic state of the cell...

..In ZAP3, although this domain is present, it now appears degenerate and functions to bind PP1 through an RVRW docking site located within the domain...

..A similar role for SPF45 is demonstrated in the activation of a cryptic 3' ss generated by a mutation that causes human beta-thalassemia...

..However, hCINAP and TAFIID32 mRNAs are translated from different ATG codons and use distinct reading frames, resulting in them having no identity in their respective protein sequences...

..This investigation provides the most detailed inventory of human spliceosome-associated factors to date, and the data indicate a number of interesting links coordinating splicing with other steps in the gene expression pathway...

..This association was confirmed by GFP-fusion protein localization. These results raise the possibility that in plants, nucleoli may have additional functions in mRNA export or surveillance...

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..Although many members of the DExH/D helicase superfamily have been linked to pre-mRNA splicing, this is the first SNF2 family member to be implicated in this pathway...

..This activity, provisionally termed 'regulator of chromosome architecture' (RCA), cooperates with condensin to preserve the characteristic chromosome architecture during mitosis...

..The developed methodology is generic and can be adapted for the identification of other sumoylation sites in complex samples...

..Furthermore, 3D3/lyric is also found in the nucleolus and is therefore a rare example of a protein that suggests a possible connection between this compartment and the endoplasmic reticulum...

..Additionally, our results provide the first evidence for a physical link between components of the ubiquitin-proteasome system and the spliceosome...

..We speculate on the relationship between CB function and molecular disease...

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