Chromatin remodelling complexes (CRCs) of the SWI/SNF family are implicated in numerous regulatory processes of eukaryotic growth, differentiation and development. Multiplicity of genes encoding SNF2-type ATPase and SWI3-type SWI/SNF CRC subunits in Arabidopsis suggests that CRCs carry different combinations of these core components. In yeast two-hybrid screens, we have identified potential auxiliary proteins of Arabidopsis SWI/SNF CRCs and analyse their in vivo interactions with CRC core components by FRET assays. We also accomplished subcellular localization of core CRC subunits by in vivo imaging and established a powerful technology for purification of SWI/SNF CRCs. Our results indicate that the BRM ATPase and ATSWI3C CRC subunits occur in common SWI/SNF complexes and mutations inactivating their genes cause similar phenotypic changes. By Affymetrix transcript profiling and qRT-PCR studies, we have identified a set of genes, which show similarly altered transcription in the atswi3c and atbrm mutants. Furthermore, we characterized genetic interactions of atswi3c mutations with known mutations that affect the functions of key genes controlling physiological and developmental responses to different hormones, and stresses. The proposed reintegration project is based on a focused multidisciplinary approach aiming at precise definition of regulatory functions of SWI/SNF CRCs. Complementary tasks of the experimental work plan aim at the i) identification of primary regulatory targets of SWI/SNF CRCs using transcriptome analysis in combination with inducible knock-down SWI3 subunits; ii) mapping of SWI/SNF-binding domains in target genes using chromatin precipitation; iii) analysis of SWI/SNF CRC-regulated functions in stresses and pathogen signalling pathways. The project is expected to provide a novel insight into regulatory mechanisms by which distinct classes of SWI/SNF CRCs participate in the control of physiological and developmental responses in Arabidopsis.