BP-80 and homologs are concentrated on post-Golgi, probable lytic prevacuolar compartments

Plant Cell Physiol. 2002 Jul;43(7):726-42. doi: 10.1093/pcp/pcf085.

Abstract

Prevacuolar compartments (PVCs) are membrane-bound organelles that mediate protein traffic between Golgi and vacuoles in the plant secretory pathway. Here we identify and define organelles as the lytic prevacuolar compartments in pea and tobacco cells using confocal immunofluorescence. We use five different antibodies specific for a vacuolar sorting receptor (VSR) BP-80 and its homologs to detect the location of VSR proteins. In addition, we use well-established Golgi-markers to identify Golgi organelles. We further compare VSR-labeled organelles to Golgi organelles so that the relative proportion of VSR proteins in Golgi vs. PVCs can be quantitated. More than 90% of the BP-80-marked organelles are separate from Golgi organelles; thus, BP-80 and its homologs are predominantly concentrated on the lytic PVCs. Additionally, organelles marked by anti-AtPep12p (AtSYP21p) and anti-AtELP antibodies are also largely separate from Golgi apparatus, whereas VSR and AtPep12p (AtSYP21p) were largely colocalized. We have thus demonstrated in plant cells that VSR proteins are predominantly present in the lytic PVCs and have provided additional markers for defining plant PVCs using confocal immunofluorescence. Additionally, our approach will provide a rapid comparison between markers to quantitate protein distribution among various organelles.

Publication types

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

MeSH terms

  • Antibodies, Monoclonal / metabolism
  • Biomarkers
  • Cell Line
  • Fluorescent Antibody Technique
  • Golgi Apparatus / metabolism*
  • Green Fluorescent Proteins
  • Luminescent Proteins / genetics
  • Luminescent Proteins / metabolism
  • Membrane Proteins / metabolism
  • Nicotiana / cytology
  • Nicotiana / metabolism
  • Organelles / metabolism*
  • Pisum sativum / cytology
  • Pisum sativum / genetics
  • Pisum sativum / metabolism
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Plant Roots / metabolism
  • Plants, Genetically Modified
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Solanum lycopersicum / cytology
  • Solanum lycopersicum / metabolism
  • Vacuoles / metabolism*
  • Vesicular Transport Proteins / genetics
  • Vesicular Transport Proteins / metabolism

Substances

  • Antibodies, Monoclonal
  • Biomarkers
  • Luminescent Proteins
  • Membrane Proteins
  • Plant Proteins
  • Recombinant Fusion Proteins
  • Vesicular Transport Proteins
  • Green Fluorescent Proteins