Clathrin and AP1B: key roles in basolateral trafficking through trans-endosomal routes.
Research following introduction of the MDCK model system to study epithelial polarity (1978) led to an initial paradigm that posited independent roles of the trans Golgi network (TGN) and recycling endosomes (RE) in the generation of, respectively, biosynthetic and recycling routes of plasma membrane (PM) proteins to apical and basolateral PM domains. This model dominated the field for 20 years. However, studies over the past decade and the discovery of the involvement of clathrin and clathrin adaptors in protein trafficking to the basolateral PM has led to a new paradigm. TGN and RE are now believed to cooperate closely in both biosynthetic and recycling trafficking routes. Here, we critically review these recent advances and the questions that remain unanswered.
Departamento de Inmunología Clínica y Reumatología, Facultad de Medicina, Centro de Regulación Celular y Patología and Centro de Envejecimiento y Regeneración, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, 6510260 Santiago, Chile. agonzara@med.puc.cl
Alfonso
A
Gonzalez
Enrique
E
Rodriguez-Boulan
D033961:Adaptor Protein Complex 1 / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D002462:Cell Membrane / Q000378:metabolism; D002966:Clathrin / Q000378:metabolism*; D011992:Endosomes / Q000378:metabolism*; D005089:Exocytosis; D006801:Humans
D033961:Adaptor Protein Complex 1; D002966:Clathrin