Biology Reference
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cadherin is cell speciic and located at intercellular junctions,
25,42
TREC images
were collected on the contact region between adjacent cells in calcium buffer
solution (i.e., HBSS containing 1.8 mM Ca
2+
) at ambient temperature. The
topography of a scanned cell surface area shows a complex picture of linear
and branched ilaments, likely representing ilaments of the peripheral actin
accurately adjusted to obtain the proper recognition with high eficiencies
and repeatability (>90%). Accordingly, a recognition signal corresponds to the
amplitude reduction due to the speciic VE-cadherin
-interaction (seen
as dark red spots in recognition image). These spots relect microdomains
trans
(a)
(b)
(b+)
(a
a
)
(b
a
)
(b++)
Figure 7.5.
Mapping VE-cadherin on the vascular endothelial cell surface with
VE-cadherin-Fc-functionalized tip. (a, a
a
) Topography images simultaneously
recorded with recognition maps b and b
, respectively. Red stars indicate the AFM
scanner lateral drift of ~5 nm/min. (b) Recognition image of VE-cadherin domains
representing an amplitude reduction due to a speciic binding between VE-cadherin
on the AFM tip and VE-cadherin molecules on the cell surface. (b
a
) The recognition
clusters practically disappeared in Ca
2+
-free conditions, since the active VE-cadherin
cis
-dimers on the AFM tip dissociated in inactive monomers, thereby abolishing
speciic VE-cadherin
trans
-interaction. After blocking with 5 mM EDTA, topography
(a
a
a
) remains unchanged, indicating that the blocking does not affect membrane
topography. (b+, b++) Examples of recognition spots taken from b. Recognition areas
are depicted by threshold analysis (threshold =
1.7 nm) and bordered by white lines.
Single VE-cadherin
cis
-dimers are clearly seen (arrows).
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