Lack of a vacuolar sorting receptor leads to non-specific missorting of soluble vacuolar proteins in Arabidopsis seeds.
The plant vacuolar sorting receptor (VSR) binds proteins carrying vacuolar sorting signals (VSS) of the 'sequence-specific' type (ssVSS) but not the C-terminal, hydrophobic sorting signals (ctVSS). Seeds of Arabidopsis mutants lacking the major VSR isoform, AtVSR1, secrete a proportion of the proteins destined to storage vacuoles. The sorting signals for these proteins are not well defined, but they do not seem to be of the ssVSS type. Here, we tested whether absence of VSR1 in seeds leads to secretion of reporter proteins carrying ssVSS but not ctVSS. Our results show that reporters carrying either ssVSS or ctVSS are equally secreted in the absence of VSR1. We discuss our findings in relation to the current model for vacuolar sorting.
Craddock
Christian P
CP
Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, UK.
Hunter
Paul R
PR
Szakacs
Erika
E
Hinz
Giselbert
G
Robinson
David G
DG
Frigerio
Lorenzo
L
D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D018744:DNA, Plant / Q000235:genetics; D017343:Genes, Plant; D017930:Genes, Reporter; D008954:Models, Biological; D009154:Mutation; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D012639:Seeds / Q000378:metabolism; D012995:Solubility; D014617:Vacuoles / Q000378:metabolism
D029681:Arabidopsis Proteins; D018744:DNA, Plant; C106564:ELP protein, Arabidopsis; D010940:Plant Proteins; C048826:phaseolin protein, Phaseolus vulgaris