Table 1.

Determinants for the polarized sorting of membrane proteins

Site Determinant Polarity Examples*
Cytoplasmic domain Tyrosine-based motif Basolateral LDL receptor, transferrin receptor, vesicular stomatitis virus glycoprotein
Dileucine motif Basolateral IgG Fc receptor, E-cadherin
PDZ-binding motif Apical/basolateral CFTR (a), BGT-1 GABA transporter (bl), ERbB-2 receptor tyrosine kinase (bl)
Others Apical/basolateral H,K-ATPase α-subunit (a), megalin (a), GAT-2 GABA transporter (bl)
Membrane anchor Transmembrane domain Apical Influenza virus hemagglutinin and neuraminidase
GPI-anchor Apical Placental alkaline phosphatase, decay-accelerating factor, Thy-1
Extracellular domain N-glycosylation Apical Occludin (truncated version), FcLR (Fc receptor-LDL receptor chimera), GLYT2 glycine transporter
O-glycosylation Apical Neurotrophin receptor, sucrase isomaltase
Oligomerization domain? Apical? Kv 1 potassium channel (neurons)
  • * a, apical; bl, basolateral.