Properties of N-terminal tails in G-protein coupled receptors: a statistical study.
The extramembraneous segments in a large collection of G-protein coupled receptors (GPCRs) have been analysed in terms of amino acid composition and length. It is shown that this family of multi-spanning integral membrane proteins conforms well to the 'positive inside' rule. Further, the extracellular N-terminal tails of GPCRs lacking a cleavable signal peptide are shown to be considerably shorter and to have a reduced content of positively charged amnio acids compared with the N-terminal tails of GPCRs endowed with a signal peptide. This suggests that extracellular N-terminal tails of eukaryotic plasma membrane proteins may be translocated by different mechanisms depending on whether or not they are preceded by a signal peptide.
Wallin
E
E
Department of Biochemistry, Arrhenius Laboratory, Stockholm University, Sweden.
von Heijne
G
G
D000595:Amino Acid Sequence; D000818:Animals; D019204:GTP-Binding Proteins / Q000737:chemistry*; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry; D008969:Molecular Sequence Data; D021382:Protein Sorting Signals / Q000737:chemistry; D011956:Receptors, Cell Surface / Q000737:chemistry*
D008565:Membrane Proteins; D021382:Protein Sorting Signals; D011956:Receptors, Cell Surface; D019204:GTP-Binding Proteins