The yeast CLC chloride channel is proteolytically processed by the furin-like protease Kex2p in the first extracellular loop.
CLC chloride channels are a family of channel proteins mediating chloride transport across the plasma membrane and intracellular membranes. The single yeast CLC protein Gef1p is localized to the Golgi and endosomal system. Investigating epitope-tagged variants of Gef1p, we found that the channel is proteolytically processed in the secretory pathway. Proteolytic cleavage occurs in the first extracellular loop of the protein at residues KR136/137 and is carried out by the Kex2p protease. Fragments mimicking the N- and C-terminal products of the cleavage reaction are non-functional when expressed alone. However, functional channels can assemble when the two fragments are co-expressed.
Wächter
Andrea
A
Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Im Neuenheimer Feld 282, D-69120 Heidelberg, Germany.
Schwappach
Blanche
B
D000595:Amino Acid Sequence; D002462:Cell Membrane / Q000378:metabolism; D018118:Chloride Channels / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D045683:Furin / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D043484:Proprotein Convertases / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment
D018118:Chloride Channels; C089713:GEF1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D043484:Proprotein Convertases; C058751:KEX2 protein, S cerevisiae; D045683:Furin