RRC ID 1877
Author Lingard MJ, Trelease RN.
Title Five Arabidopsis peroxin 11 homologs individually promote peroxisome elongation, duplication or aggregation.
Journal J. Cell. Sci.
Abstract Pex11 homologs and dynamin-related proteins uniquely regulate peroxisome division (cell-cycle-dependent duplication) and proliferation (cell-cycle-independent multiplication). Arabidopsis plants possess five Pex11 homologs designated in this study as AtPex11a, -b, -c, -d and -e. Transcripts for four isoforms were found in Arabidopsis plant parts and in cells in suspension culture; by contrast, AtPex11a transcripts were found only in developing siliques. Within 2.5 hours after biolistic bombardments, myc-tagged or GFP-tagged AtPex11 a, -b, -c, -d and -e individually sorted from the cytosol directly to peroxisomes; none trafficked indirectly through the endoplasmic reticulum. Both termini of myc-tagged AtPex11 b, -c, -d and -e faced the cytosol, whereas the N- and C-termini of myc-AtPex11a faced the cytosol and matrix, respectively. In AtPex11a- or AtPex11e-transformed cells, peroxisomes doubled in number. Those peroxisomes bearing myc-AtPex11a, but not myc-AtPex11e, elongated prior to duplication. In cells transformed with AtPex11c or AtPex11d, peroxisomes elongated without subsequent fission. In AtPex11b-transformed cells, peroxisomes were aggregated and rounded. A C-terminal dilysine motif, present in AtPex11c, -d and -e, was not necessary for AtPex11d-induced peroxisome elongation. However, deletion of the motif from myc-AtPex11e led to peroxisome elongation and fission, indicating that the motif in this isoform promotes fission without elongation. In summary, all five overexpressed AtPex11 isoforms sort directly to peroxisomal membranes where they individually promote duplication (AtPex11a, -e), aggregation (AtPex11b), or elongation without fission (AtPex11c, -d).
Volume 119(Pt 9)
Pages 1961-72
Published 2006-5-1
DOI 10.1242/jcs.02904
PII 119/9/1961
PMID 16636080
MeSH Amino Acid Sequence Arabidopsis / cytology Arabidopsis / metabolism Arabidopsis Proteins / genetics Arabidopsis Proteins / metabolism* Cytoplasm / metabolism Membrane Proteins / genetics Membrane Proteins / metabolism* Molecular Sequence Data Peroxins Peroxisomes / genetics Peroxisomes / metabolism* Peroxisomes / ultrastructure* Protein Isoforms / genetics Protein Isoforms / metabolism* Protein Transport / physiology Recombinant Fusion Proteins / genetics Recombinant Fusion Proteins / metabolism Sequence Alignment Sequence Analysis, DNA Tobacco / cytology Tobacco / metabolism
IF 4.401
Times Cited 49
Arabidopsis / Cultured plant cells, genes pda04235