Fig. 5.

Amino acid substitutions in the second extracellular loop of claudin-5 (Cld5) did not alter the morphology of tight junction strands. MDCK-II cells, stably transfected with control vector, Cld5_wt, Cld5_R145A or Cld5_Y148A were fixed and processed for freeze-fracture electron microscopy. In all cases similar network-like intramembranous strands, associated with protoplasmic face (PF) but not with the exoplasmic face (EF), were found