title: Cloning and subcellular location of an Arabidopsis receptor-like protein that shares common features with protein-sorting receptors of eukaryotic cells.
abstract: Many receptors involved in clathrin-mediated protein transport through the endocytic and secretory pathways of yeast and animal cells share common features. They are all type I integral membrane proteins containing cysteine-rich lumenal domains and cytoplasmic tails with tyrosine-containing sorting signals. The cysteine-rich domains are thought to be involved in ligand binding, whereas the cytoplasmic tyrosine motifs interact with clathrin-associated adaptor proteins during protein sorting along these pathways. In addition, tyrosine-containing signals are required for the retention and recycling of some of these membrane proteins to the trans-Golgi network. Here we report the characterization of an approximately 80-kD epidermal growth factor receptor-like type I integral membrane protein containing all of these functional motifs from Arabidopsis thaliana (called AtELP for A. thaliana Epidermal growth factor receptor-Like Protein). Biochemical analysis indicates that AtELP is a membrane protein found at high levels in the roots of both monocots and dicots. Subcellular fractionation studies indicate that the AtELP protein is present in two membrane fractions corresponding to a novel, undefined compartment and a fraction enriched in vesicles containing clathrin and its associated adaptor proteins. AtELP may therefore serve as a marker for compartments involved in intracellular protein trafficking in the plant cell.
authors.affiliation: Michigan State University-Department of Energy Plant Research Laboratory, East Lansing 48824-1312, USA.
authors.forename: S U
authors.initials: SU
authors.lastname: Ahmed
authors.forename: M
authors.initials: M
authors.lastname: Bar-Peled
authors.forename: N V
authors.initials: NV
authors.lastname: Raikhel
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism*; D029681:Arabidopsis Proteins; D001693:Biological Transport, Active; D002451:Cell Compartmentation; D002966:Clathrin / Q000378:metabolism; D003001:Cloning, Molecular; D017124:Conserved Sequence; D018076:DNA, Complementary / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism; D005057:Eukaryotic Cells / Q000378:metabolism; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D013347:Subcellular Fractions / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D002966:Clathrin; D018076:DNA, Complementary; D018744:DNA, Plant; C106564:ELP protein, Arabidopsis; D010940:Plant Proteins; D066246:ErbB Receptors