Demonstration in Yeast of the Function of BP-80, a Putative Plant Vacuolar Sorting Receptor

AUTOR(ES)

Humair, David

FONTE

American Society of Plant Physiologists

RESUMO

BP-80, later renamed VSRPS-1, is a putative receptor involved in sorting proteins such as proaleurain to the lytic vacuole, with its N-terminal domain recognizing the vacuolar sorting determinant. Although all VSRPS-1 characteristics and in vitro binding properties described so far favored its receptor function, this function remained to be demonstrated. Here, we used green fluorescent protein (GFP) as a reporter in a yeast mutant strain defective for its own vacuolar receptor, Vps10p. By expressing VSRPS-1 together with GFP fused to the vacuolar sorting determinant of petunia proaleurain, we were able to efficiently redirect the reporter to the yeast vacuole. VSRPS-1 is ineffective on GFP either alone or when fused with another type of plant vacuolar sorting determinant from a chitinase. The plant VSRPS-1 therefore interacts specifically with the proaleurain vacuolar sorting determinant in vivo, and this interaction leads to the transport of the reporter protein through the yeast secretory pathway to the vacuole. This finding demonstrates VSRPS-1 receptor function but also emphasizes the differences in the spectrum of ligands between Vps10p and its plant equivalent.

Documentos Relacionados

• Vacuolar storage proteins and the putative vacuolar sorting receptor BP-80 exit the golgi apparatus of developing pea cotyledons in different transport vesicles
• Molecular cloning and further characterization of a probable plant vacuolar sorting receptor.
• Structural Requirements for Ligand Binding by a Probable Plant Vacuolar Sorting Receptor
• Characterization of genes required for protein sorting and vacuolar function in the yeast Saccharomyces cerevisiae.
• The Yeast Saccharomyces cerevisiae Is Not an Efficient Tool for in Vivo Studies of Plant Vacuolar Sorting ReceptorsW⃞