title: The Arabidopsis cohesin protein SYN3 localizes to the nucleolus and is essential for gametogenesis.
abstract: Alpha-kleisins are core components of meiotic and mitotic cohesin complexes. Arabidopsis contains genes for four alpha-kleisin proteins encoded by SYN genes. SYN1, a REC8 ortholog, is essential for meiosis, while SYN2 and SYN4 appear to be SCC1 orthologs and function in mitosis. Our analysis of AtSYN3 shows that it localizes primarily in the nucleolus of both meiotic and mitotic cells. Furthermore, analysis of plants containing an AtSYN3 T-DNA knockout mutation demonstrated that it is essential for megagametogenesis and plays an important role in pollen. These results suggest that SYN3 may not function as part of a typical cohesin complex; rather it may have evolved a specialized role in controlling rDNA structure, transcription or rRNA processing.
authors.affiliation: Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA.
authors.forename: Ling
authors.initials: L
authors.lastname: Jiang
authors.forename: Ming
authors.initials: M
authors.lastname: Xia
authors.forename: Lara I
authors.initials: LI
authors.lastname: Strittmatter
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Makaroff
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000378:metabolism*; D002466:Cell Nucleolus / Q000378:metabolism*; D005718:Gametogenesis / Q000502:physiology*; D008540:Meiosis / Q000502:physiology; D016254:Mutagenesis, Insertional; D030821:Plants, Genetically Modified; D011058:Pollen / Q000254:growth & development* / Q000648:ultrastructure
chemical_list: D029681:Arabidopsis Proteins; D018797:Cell Cycle Proteins; C432545:SYN3 protein, Arabidopsis