Tight junction modulation and biochemical characterisation of the zonula occludens toxin C-and N-termini.
The ZOT N-terminal domain was expressed and refolded, yielding a soluble protein with defined secondary structure. Although distantly related to protein I of filamentous phages, no evidence of ATPase activity was found. It is therefore unlikely that the ZOT N-terminal domain is involved in cholera toxin phage packaging in Vibrio cholerae. The ZOT C-terminal domain caused delocalisation of occludin and ZO-1 from Caco-2 cell-cell contacts, irrespective of disulfide bridge formation in its putative binding domain. However, the C-terminal domain did not cause actin reorganisation and this may explain the absence of a concomitant reduction in the transepithelial electrical resistance across cell monolayers.
Schmidt
E
E
Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 27 Taylor Street, Glasgow, UK.
Kelly
S M
SM
van der Walle
C F
CF
D000199:Actins / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000378:metabolism; D000595:Amino Acid Sequence; D018938:Caco-2 Cells; D002772:Cholera Toxin / Q000737:chemistry* / Q000494:pharmacology*; D004731:Endotoxins; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D008969:Molecular Sequence Data; D062793:Occludin; D010750:Phosphoproteins / Q000378:metabolism; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D019108:Tight Junctions / Q000187:drug effects*; D062826:Zonula Occludens-1 Protein
D000199:Actins; D004731:Endotoxins; D008565:Membrane Proteins; C568985:OCLN protein, human; D062793:Occludin; D010750:Phosphoproteins; C569042:TJP1 protein, human; D062826:Zonula Occludens-1 Protein; C077728:zonula occludens toxin, Vibrio cholerae; D002772:Cholera Toxin; D000251:Adenosine Triphosphatases