The newly identified yeast GRD genes are required for retention of late-Golgi membrane proteins.
Processing of A-ALP, a late-Golgi membrane protein constructed by fusing the cytosolic domain of dipeptidyl aminopeptidase A to the transmembrane and lumenal domains of alkaline phosphatase (ALP), serves as a convenient assay for loss of retention of late-Golgi membrane proteins in Saccharomyces cerevisiae. In this study, a large group of novel grd (for Golgi retention defective) yeast mutants, representing 18 complementation groups, were identified on the basis of their mislocalization of A-ALP to the vacuole, where it was proteolytically processed and thus became enzymatically activated. All of the grd mutants exhibited significant mislocalization of A-ALP, as measured by determining the kinetics of A-ALP processing and by analyzing its
Nothwehr
S F
SF
Division of Biological Sciences, University of Missouri, Columbia 65211, USA.
Bryant
N J
NJ
Stevens
T H
TH
D000469:Alkaline Phosphatase / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D005800:Genes, Fungal; D005816:Genetic Complementation Test; D006056:Golgi Apparatus / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D007703:Peptidyl-Dipeptidase A / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D011499:Protein Processing, Post-Translational; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D014617:Vacuoles / Q000378:metabolism
D005656:Fungal Proteins; D008565:Membrane Proteins; D011993:Recombinant Fusion Proteins; D000469:Alkaline Phosphatase; D007703:Peptidyl-Dipeptidase A