Objective Unlike previously thought the nucleus is a highly compartmentalized organelle. Both the genome and processes associated with it show non-random distribution within the nucleus. This compartmentalization has a fundamental impact on nuclear processes. However, the mechanisms driving this organization are poorly understood. I hypothesize that actin plays a key role in this process. Nevertheless, the true potential of nuclear actin has not been fully appreciated, due to two fundamental open questions in this field, namely 1) what is the biological significance of nuclear actin and 2) what is the molecular mechanism by which actin operates in the nucleus? I intend to address these key questions by manipulating actin specifically in the nucleus, and by identifying nuclear actin binding partners, respectively. My lab has recently identified the nuclear import mechanism for actin, which offers us a unique tool to manipulate nuclear actin. We will therefore create cell lines with decreased/increased nuclear actin, and analyze the consequences by using cell biological and gene expression tools, combined with deep sequencing. This will disclose the genes that depend on actin for their expression, and reveal the biological significance of nuclear actin in organizing the general nuclear landscape. To unravel the mechanisms by which actin functions in the nucleus, we will implement a novel multi-readout, fluorescence microscopy screen to identify nuclear actin binding proteins, which will be analyzed by different biochemical methods. This approach will reveal how actin is connected to nuclear machineries, and what biochemical features of actin are required to power the essential nuclear processes. These techniques will significantly broaden our understanding on the nuclear functions of actin, and thus likely reveal molecular mechanisms that regulate nuclear organization, which are highly relevant to basic biological processes, such as cell differentiation and epigenetics. Fields of science natural sciencesbiological sciencesbiochemistrybiomoleculesproteinsnatural sciencesphysical sciencesopticsmicroscopynatural sciencesbiological sciencesgeneticsgenomesnatural sciencesbiological sciencesgeneticsepigenetics Programme(s) FP7-IDEAS-ERC - Specific programme: "Ideas" implementing the Seventh Framework Programme of the European Community for research, technological development and demonstration activities (2007 to 2013) Topic(s) ERC-SG-LS1 - ERC Starting Grant - Molecular and Structural Biology and Biochemistry Call for proposal ERC-2012-StG_20111109 See other projects for this call Funding Scheme ERC-SG - ERC Starting Grant Host institution HELSINGIN YLIOPISTO EU contribution € 1 491 484,00 Address YLIOPISTONKATU 3 00014 Helsingin Yliopisto Finland See on map Region Manner-Suomi Helsinki-Uusimaa Helsinki-Uusimaa Activity type Higher or Secondary Education Establishments Administrative Contact Tuija Modinos (Ms.) Principal investigator Maria Kristina Vartiainen (Dr.) Links Contact the organisation Opens in new window Website Opens in new window Total cost No data Beneficiaries (1) Sort alphabetically Sort by EU Contribution Expand all Collapse all HELSINGIN YLIOPISTO Finland EU contribution € 1 491 484,00 Address YLIOPISTONKATU 3 00014 Helsingin Yliopisto See on map Region Manner-Suomi Helsinki-Uusimaa Helsinki-Uusimaa Activity type Higher or Secondary Education Establishments Administrative Contact Tuija Modinos (Ms.) Principal investigator Maria Kristina Vartiainen (Dr.) Links Contact the organisation Opens in new window Website Opens in new window Total cost No data