The Arabidopsis SYN3 cohesin protein is important for early meiotic events

Plant J. 2012 Jul;71(1):147-60. doi: 10.1111/j.1365-313X.2012.04979.x. Epub 2012 Apr 30.


α-Kleisins are core components of meiotic and mitotic cohesin complexes. Arabidopsis contains four genes that encode α-kleisin proteins: SYN1, SYN2, SYN3 and SYN4. SYN1, a REC8 ortholog, is essential for meiosis, while SYN2 and SYN4 appear to be SCC1 orthologs and function in mitosis. SYN3 is essential for megagametogenesis and is enriched in the nucleolus of meiotic and mitotic cells. In this study the role of SYN3 during meiosis was investigated by characterization of plants that express SYN3-RNAi constructs from either meiotic DMC1, native SYN3, or inducible PX7 promoters. Reduction of SYN3 caused defects in homologous chromosome synapsis and synaptonemal complex (SC) formation during male and female meiosis. Consistent with this observation, relatively little signal for the SC component ZYP1 was detected on the chromosomes of SYN3-RNAi plants. ZYP1 transcript levels were relatively normal, but several transcripts for genes that encode proteins involved in meiotic recombination were altered, which suggested that a reduction in SYN3 may inhibit meiotic progression by alteration of meiotic gene expression.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Arabidopsis / genetics*
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism*
  • Chromosome Pairing*
  • Gene Expression Regulation, Developmental
  • Gene Expression Regulation, Plant
  • Germ Cells, Plant / growth & development
  • Meiosis*
  • Plants, Genetically Modified / genetics
  • Plants, Genetically Modified / metabolism
  • Promoter Regions, Genetic
  • RNA Interference


  • Arabidopsis Proteins
  • Cell Cycle Proteins
  • SYN3 protein, Arabidopsis
  • ZYP1a protein, Arabidopsis