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Conversion of zonulae occludentes from tight to leaky strand type by introducing claudin-2 into Madin-Darby canine kidney I cells.

Furuse M, Furuse K, Sasaki H, Tsukita S - J. Cell Biol. (2001)

Bottom Line: Interestingly, the TER values of MDCK I clones stably expressing claudin-2 (dCL2-MDCK I) fell to the levels of MDCK II cells (>20-fold decrease).Similar results were obtained in mouse epithelial cells, Eph4.These findings indicated that the addition of claudin-2 markedly decreased the tightness of individual claudin-1/4-based TJ strands, leading to the speculation that the combination and mixing ratios of claudin species determine the barrier properties of individual TJ strands.

View Article: PubMed Central - PubMed

Affiliation: Department of Cell Biology, Faculty of Medicine, Kyoto University, Kyoto 606-8501, Japan.

ABSTRACT
There are two strains of MDCK cells, MDCK I and II. MDCK I cells show much higher transepithelial electric resistance (TER) than MDCK II cells, although they bear similar numbers of tight junction (TJ) strands. We examined the expression pattern of claudins, the major components of TJ strands, in these cells: claudin-1 and -4 were expressed both in MDCK I and II cells, whereas the expression of claudin-2 was restricted to MDCK II cells. The dog claudin-2 cDNA was then introduced into MDCK I cells to mimic the claudin expression pattern of MDCK II cells. Interestingly, the TER values of MDCK I clones stably expressing claudin-2 (dCL2-MDCK I) fell to the levels of MDCK II cells (>20-fold decrease). In contrast, when dog claudin-3 was introduced into MDCK I cells, no change was detected in their TER. Similar results were obtained in mouse epithelial cells, Eph4. Morphometric analyses identified no significant differences in the density of TJs or in the number of TJ strands between dCL2-MDCK I and control MDCK I cells. These findings indicated that the addition of claudin-2 markedly decreased the tightness of individual claudin-1/4-based TJ strands, leading to the speculation that the combination and mixing ratios of claudin species determine the barrier properties of individual TJ strands.

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Distribution of the frequency of observation of a given number of TJ strands in dCL2-MDCK I (clones 2 and 4) and neo-MDCK I cells (clones 7 and 8). Using printed pictures of freeze-fracture replica images (Fig. 5), we took numerous counts along a line drawn perpendicular to the junctional axis at 200-nm intervals (Sonoda et al. 1999). From these distribution curves, the mean TJ strand number was determined for each clone (Table ).
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Figure 6: Distribution of the frequency of observation of a given number of TJ strands in dCL2-MDCK I (clones 2 and 4) and neo-MDCK I cells (clones 7 and 8). Using printed pictures of freeze-fracture replica images (Fig. 5), we took numerous counts along a line drawn perpendicular to the junctional axis at 200-nm intervals (Sonoda et al. 1999). From these distribution curves, the mean TJ strand number was determined for each clone (Table ).

Mentions: Then, we examined TJs of the above clones of dCL2-MDCK I and neo-MDCK I cells by freeze–fracture electron microscopy. As shown in Fig. 5, the network pattern of TJ strands of dCL2-MDCK I clones was very similar to that of neo-MDCK I clones. To compare these networks quantitatively, the mean number of TJ strands in each clone was determined by making numerous counts of TJ strands along a line drawn perpendicular to the junctional axis according to the method described previously (Stevenson et al. 1988). As summarized in Fig. 6 and Table , although the mean number of TJ strands varied to some extent, there was no tendency for the number of strands in dCL2-MDCK I clones to be less than that of neo-MDCK I clones.


Conversion of zonulae occludentes from tight to leaky strand type by introducing claudin-2 into Madin-Darby canine kidney I cells.

Furuse M, Furuse K, Sasaki H, Tsukita S - J. Cell Biol. (2001)

Distribution of the frequency of observation of a given number of TJ strands in dCL2-MDCK I (clones 2 and 4) and neo-MDCK I cells (clones 7 and 8). Using printed pictures of freeze-fracture replica images (Fig. 5), we took numerous counts along a line drawn perpendicular to the junctional axis at 200-nm intervals (Sonoda et al. 1999). From these distribution curves, the mean TJ strand number was determined for each clone (Table ).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2169456&req=5

Figure 6: Distribution of the frequency of observation of a given number of TJ strands in dCL2-MDCK I (clones 2 and 4) and neo-MDCK I cells (clones 7 and 8). Using printed pictures of freeze-fracture replica images (Fig. 5), we took numerous counts along a line drawn perpendicular to the junctional axis at 200-nm intervals (Sonoda et al. 1999). From these distribution curves, the mean TJ strand number was determined for each clone (Table ).
Mentions: Then, we examined TJs of the above clones of dCL2-MDCK I and neo-MDCK I cells by freeze–fracture electron microscopy. As shown in Fig. 5, the network pattern of TJ strands of dCL2-MDCK I clones was very similar to that of neo-MDCK I clones. To compare these networks quantitatively, the mean number of TJ strands in each clone was determined by making numerous counts of TJ strands along a line drawn perpendicular to the junctional axis according to the method described previously (Stevenson et al. 1988). As summarized in Fig. 6 and Table , although the mean number of TJ strands varied to some extent, there was no tendency for the number of strands in dCL2-MDCK I clones to be less than that of neo-MDCK I clones.

Bottom Line: Interestingly, the TER values of MDCK I clones stably expressing claudin-2 (dCL2-MDCK I) fell to the levels of MDCK II cells (>20-fold decrease).Similar results were obtained in mouse epithelial cells, Eph4.These findings indicated that the addition of claudin-2 markedly decreased the tightness of individual claudin-1/4-based TJ strands, leading to the speculation that the combination and mixing ratios of claudin species determine the barrier properties of individual TJ strands.

View Article: PubMed Central - PubMed

Affiliation: Department of Cell Biology, Faculty of Medicine, Kyoto University, Kyoto 606-8501, Japan.

ABSTRACT
There are two strains of MDCK cells, MDCK I and II. MDCK I cells show much higher transepithelial electric resistance (TER) than MDCK II cells, although they bear similar numbers of tight junction (TJ) strands. We examined the expression pattern of claudins, the major components of TJ strands, in these cells: claudin-1 and -4 were expressed both in MDCK I and II cells, whereas the expression of claudin-2 was restricted to MDCK II cells. The dog claudin-2 cDNA was then introduced into MDCK I cells to mimic the claudin expression pattern of MDCK II cells. Interestingly, the TER values of MDCK I clones stably expressing claudin-2 (dCL2-MDCK I) fell to the levels of MDCK II cells (>20-fold decrease). In contrast, when dog claudin-3 was introduced into MDCK I cells, no change was detected in their TER. Similar results were obtained in mouse epithelial cells, Eph4. Morphometric analyses identified no significant differences in the density of TJs or in the number of TJ strands between dCL2-MDCK I and control MDCK I cells. These findings indicated that the addition of claudin-2 markedly decreased the tightness of individual claudin-1/4-based TJ strands, leading to the speculation that the combination and mixing ratios of claudin species determine the barrier properties of individual TJ strands.

Show MeSH