title: SWI3 subunits of putative SWI/SNF chromatin-remodeling complexes play distinct roles during Arabidopsis development.
abstract: SWITCH/SUCROSE NONFERMENTING (SWI/SNF) chromatin-remodeling complexes mediate ATP-dependent alterations of DNA-histone contacts. The minimal functional core of conserved SWI/SNF complexes consists of a SWI2/SNF2 ATPase, SNF5, SWP73, and a pair of SWI3 subunits. Because of early duplication of the SWI3 gene family in plants, Arabidopsis thaliana encodes four SWI3-like proteins that show remarkable functional diversification. Whereas ATSWI3A and ATSWI3B form homodimers and heterodimers and interact with BSH/SNF5, ATSWI3C, and the flowering regulator FCA, ATSWI3D can only bind ATSWI3B in yeast two-hybrid assays. Mutations of ATSWI3A and ATSWI3B arrest embryo development at the globular stage. By a possible imprinting effect, the atswi3b mutations result in death for approximately half of both macrospores and microspores. Mutations in ATSWI3C cause semidwarf stature, inhibition of root elongation, leaf curling, aberrant stamen development, and reduced fertility. Plants carrying atswi3d mutations display severe dwarfism, alterations in the number and development of flower organs, and complete male and female sterility. These data indicate that, by possible contribution to the combinatorial assembly of different SWI/SNF complexes, the ATSWI3 proteins perform nonredundant regulatory functions that affect embryogenesis and both the vegetative and reproductive phases of plant development.
authors.affiliation: Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland.
authors.forename: Tomasz J
authors.initials: TJ
authors.lastname: Sarnowski
authors.forename: Gabino
authors.initials: G
authors.lastname: Ríos
authors.forename: Jan
authors.initials: J
authors.lastname: Jásik
authors.forename: Szymon
authors.initials: S
authors.lastname: Swiezewski
authors.forename: Szymon
authors.initials: S
authors.lastname: Kaczanowski
authors.forename: Yong
authors.initials: Y
authors.lastname: Li
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Kwiatkowska
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Pawlikowska
authors.forename: Marta
authors.initials: M
authors.lastname: Koźbiał
authors.forename: Piotr
authors.initials: P
authors.lastname: Koźbiał
authors.forename: Csaba
authors.initials: C
authors.lastname: Koncz
authors.forename: Andrzej
authors.initials: A
authors.lastname: Jerzmanowski
mesh_terms: D000818:Animals; D017360:Arabidopsis / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D002843:Chromatin / Q000378:metabolism*; D018744:DNA, Plant; D006801:Humans; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D005810:Multigene Family; D009154:Mutation; D010802:Phylogeny; D020033:Protein Isoforms / Q000145:classification / Q000235:genetics / Q000378:metabolism; D021122:Protein Subunits / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
chemical_list: C463463:ATSWI3B protein, Arabidopsis; D029681:Arabidopsis Proteins; D002843:Chromatin; D018744:DNA, Plant; D046911:Macromolecular Substances; D020033:Protein Isoforms; D021122:Protein Subunits; D016601:RNA-Binding Proteins