title: Nuclear envelope dynamics during plant cell division suggest common mechanisms between kingdoms.
abstract: Behaviour of the NE (nuclear envelope) during open mitosis has been explored extensively in metazoans, but lack of native markers has limited similar investigations in plants. In the present study, carried out using living synchronized tobacco BY-2 suspension cultures, the non-functional NE marker LBR (lamin B receptor)-GFP (green fluorescent protein) and two native, functional NE proteins, AtSUN1 [Arapidopsis thaliana SUN (Sad1/UNC84) 1] and AtSUN2, we provide evidence that the ER (endoplasmic reticulum)-retention theory for NE membranes is applicable in plants. We also observe two apparently unique plant features: location of the NE-membrane components in close proximity to chromatin throughout division, and spatially distinct reformation of the NE commencing at the chromatin surface facing the spindle poles and concluding at the surface facing the cell plate. Mobility of the proteins was investigated in the interphase NE, during NE breakdown and reformation, in the spindle membranes and the cell plate. A role for AtSUN2 in nuclear envelope breakdown is suggested.
authors.affiliation: School of Life Sciences, Oxford Brookes University, Oxford OX3 0BP, UK.
authors.forename: Katja
authors.initials: K
authors.lastname: Graumann
authors.forename: David E
authors.initials: DE
authors.lastname: Evans
mesh_terms: D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D015415:Biomarkers; D002460:Cell Line; D004721:Endoplasmic Reticulum / Q000502:physiology; D018506:Gene Expression Regulation, Plant / Q000502:physiology; D049452:Green Fluorescent Proteins; D008938:Mitosis / Q000502:physiology*; D009154:Mutation; D009685:Nuclear Envelope / Q000502:physiology*; D038761:Photobleaching; D017434:Protein Structure, Tertiary; D013045:Species Specificity; D014026:Nicotiana / Q000166:cytology*
chemical_list: D029681:Arabidopsis Proteins; D015415:Biomarkers; D049452:Green Fluorescent Proteins