Par-1 promotes a hepatic mode of apical protein trafficking in MDCK cells Academic Article uri icon


MeSH Major

  • Liver
  • Protein-Serine-Threonine Kinases


  • Simple (i.e., nonstratified) epithelial cells use two different routes to target their newly synthesized luminal plasma membrane proteins to the cell surface: a direct route from the Golgi complex, as in the kidney-derived MDCK cell line, or an indirect route that involves a intermediate stop at the ab-luminal (basolateral) membrane, as in hepatocytes. The mechanisms or proteins responsible for these different protein targeting strategies are not known. Here, we show that increased expression of EMK1, a mammalian ortholog of Caenorhabditis elegans Par-1, in MDCK cells promotes a switch from a direct to a transcytotic mode of apical protein delivery and other trafficking changes typical of hepatocytes. These results, together with our recent demonstration that PAR-1 promotes morphological features of hepatocytes in MDCK cells, indicate that Par-1 modulates the developmental decision to build a columnar versus a hepatic epithelial cell. To our knowledge, Par-1 is the first gene assigned to this task in epithelial morphogenesis.

publication date

  • September 21, 2004



  • Academic Article



  • eng

PubMed Central ID

  • PMC518835

Digital Object Identifier (DOI)

  • 10.1073/pnas.0403684101

PubMed ID

  • 15365179

Additional Document Info

start page

  • 13792

end page

  • 7


  • 101


  • 38