Center for Research on Reproduction and Women's Health, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
* Author for correspondence (e-mail: radice{at}mail.med.upenn.edu)
Accepted 23 December 2002
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Summary |
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Key words: N-cadherin, Cardiomyocyte, Myofibrillogenesis, Gap junctions, Focal contacts
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Introduction |
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The cadherin family of calcium-dependent cell adhesion molecules plays an
important role in establishing and maintaining cell-cell interactions through
its homotypic binding and adhesive specificities
(Tepass et al., 2000).
Cadherins are single-pass transmembrane proteins that interact intracellularly
with a group of proteins called catenins, which mediate cadherin linkage to
the actin cytoskeleton (Gumbiner,
2000
). The catenin family consists of several members including
E-,
N-,
T-, ß- and
-catenin (plakoglobin),
and p120ctn. Either ß-catenin or plakoglobin binds directly to the
C-terminal region of cadherin, and one of the
-catenin isoforms links
the cadherin-catenin complex directly
(Rimm et al., 1995
) or
indirectly (Knudsen et al.,
1995
; Watabe-Uchida et al.,
1998
) to the actin cytoskeleton.
T-catenin, a recently
identified member of the catenin family, is highly expressed in heart, where
it localizes to the intercalated disc
(Janssens et al., 2001
). The
strength of adhesion is also modulated by p120ctn, which binds the
juxtamembrane region of the cadherin cytoplasmic domain
(Anastasiadis and Reynolds,
2000
). Their adhesive specificity and cellular distribution during
embryogenesis suggest an important role for cadherins in morphogenesis and
maintenance of the tissue phenotype.
N-cadherin is expressed by the developing and mature myocardium, where it
is found predominantly in the fascia adherens of the transverse region of
intercalated disks and in the regions of close lateral contact between
neighboring myocytes (Duband et al.,
1988; Hatta et al.,
1987
; Kostin et al.,
1999
; Volk and Geiger,
1984
; Volk and Geiger,
1986
). It is also found in extrajunctional sites called costameres
(Pardo et al., 1983
) where it
colocalizes with
-actinin in the peripheral Z-disks of the sarcomeres
(Goncharova et al., 1992
;
Wu et al., 1999
;
Wu et al., 2002
). Much of our
knowledge on how N-cadherin might function in cardiomyocyte adhesion and
myofibrillogenesis comes from in vitro studies employing antibodies that block
specifically the function of N-cadherin. In these investigations, blocking
N-cadherin function decreased cell-cell contact between interacting myocytes
as well as disrupted myofibril organization
(Goncharova et al., 1992
;
Peralta Soler and Knudsen,
1994
; Wu et al.,
1999
) and formation
(Imanaka-Yoshida et al.,
1998
). A similar result was obtained with a dominant-negative
N-cadherin construct microinjected into adult rat cardiomyocytes
(Hertig et al., 1996b
).
Observations of interactions between living adult rat cardiomyocytes
demonstrated recruitment of a N-cadherin/EGFP fusion protein to regions of
initial cell-cell contact, which appeared to serve as insertion sites for
stress-fiber-like actin-containing structures
(Zuppinger et al., 2000
).
Consistent with a role for cadherin-mediated adhesion in gap junction
formation (Frenzel and Johnson,
1996
; Hertig et al.,
1996b
; Jongen et al.,
1991
; Meyer et al.,
1992
), the N-cadherin/EGFP fusion protein appeared before connexin
43 (Cx43) at newly established cell-cell contact sites between the myocytes.
In the present study, we further demonstrate the importance of N-cadherin in
maintaining proper cytoarchitecture of the cardiomyocyte required for normal
myofibril contractility between the cells as well as for gap junction
formation.
E-cadherin plays an important role in the maintenance of the epithelial
phenotype and its downregulation is involved in tumor progression
(Conacci-Sorrell et al., 2002).
Mouse N- and E-cadherin show 49% amino acid similarity overall and in vitro
studies indicate that N- and E-cadherin do not interact in either cis or trans
(Miyatani et al., 1989
;
Shan et al., 2000
). We
recently demonstrated that cardiac-specific expression of E-cadherin could
restore cell adhesion and looping morphogenesis in N-cadherin-null embryos
(Luo et al., 2001
). However,
we did find that misexpression of E-cadherin in the adult myocardium led to
severe cardiomyopathy in transgenic mice due to defects in the intercalated
discs (Ferreira-Cornwell et al.,
2002
). In the present study, we examine E-cadherin-mediated
myofibril organization in cultured N-cadherin-null myocytes.
Cell-ECM interactions are also important determinants of myocyte
cytoarchitecture, providing structural integrity necessary for normal
sarcomere organization (Ross and Borg,
2001). The integrin family of cell adhesion receptors mediates
these interactions by binding to the substrata components, including
collagens, fibronectins and laminins. Similar to N-cadherin, ß1 integrin
is expressed in the developing and mature myocardium
(Carver et al., 1994
;
Terracio et al., 1991
). In the
presence of anti-ß1 integrin antibodies, normal cell spreading and
myofibril organization was perturbed in cultured neonatal rat cardiomyocytes
(Hilenski et al., 1992
).
Myocytes derived from ß1 integrin double-knockout embryonic stem (ES)
cells exhibited altered in vitro differentiation and abnormal sarcomeric
architecture (Fassler et al.,
1996
). Recently, the gene encoding ß1 integrin was deleted
specifically from ventricular myocytes, resulting in dilated cardiomyopathy in
mice (Shai et al., 2002
). In
summary, over the past 10 years, numerous studies have indicated that both the
integrin and cadherin adhesion systems are important for maintenance of
myofibril structure.
The structural integrity of the nascent myocardium is severely perturbed in
N-cadherin-null embryos, resulting in early lethality
(Radice et al., 1997) and
making it difficult to study the cellular characteristics of the mutant
myocytes in vivo. In this study, we circumvented this problem by examining
myocyte cultures derived from mutant and rescued
(Luo et al., 2001
) embryos. In
contrast to previous in vitro studies, we found that N-cadherin is not
required for myofibrillogenesis, but is essential for proper alignment of the
myofibrils across the plasma membrane. In addition, an epithelial cadherin,
E-cadherin, was capable of anchoring actin filaments into the membrane and
thus restoring myofibril organization in the N-cadherin-null myocytes,
demonstrating that these classical cadherins are interchangeable in this
particular cellular context.
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Materials and Methods |
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Myocyte cultures and immunohistochemistry
Embryos were collected on either embryonic day (E)9.0 (mutant) or E10.5
(rescued), and the yolk sac from each embryo was harvested for genotyping by
PCR analysis (Luo et al.,
2001). In this study, `rescued' embryos are defined as mutant
embryos expressing the
MHC/E-cadherin transgene
(Ncad/; Ecad+). Heart tubes were isolated,
trypsinized and plated on fibronectin-coated coverslips in 24-well dishes. The
myocytes were cultured in DMEM with high glucose and 15% FBS. Although the
recovery of cardiac cells from the mutant embryos was variable, the remaining
attached myocytes appeared normal as demonstrated by their well-formed
myofibrils and ability to contract in the culture dish. After three days, the
cultures were observed with a Nikon inverted microscope, and were photographed
and fixed in freshly prepared 4% paraformaldehyde for 15 minutes at room
temperature. The cells were washed with PBS, and treated with 0.5% Triton
X-100/PBS for 10 minutes. The samples were washed in PBS before blocking with
5% skim milk/PBS for 30 minutes. Antibodies were diluted in 5% skim milk/PBS
as follows: mouse monoclonal anti-N-cadherin, 1:100 (3B9; Zymed, South San
Francisco, CA); mouse monoclonal anti-E-cadherin, 1:100 (4A2C7; Zymed); mouse
monoclonal anti-sarcomeric
-actinin, 1:100 (EA-53, Sigma); mouse
monoclonal anti-ß-catenin, 1:100 (CAT-5H10; Zymed); rabbit polyclonal
anti-Cx43, 1:100 (Zymed); mouse monoclonal anti-vinculin, 1:500 (Sigma); mouse
monoclonal anti-p120ctn, 1:400 (#98, Transduction Laboratories, Lexington,
KT); mouse monoclonal anti-desmosomal protein, 1:100 (ZK-31, Sigma); rat
monoclonal anti-ß1 integrin, 1:500 (Transduction Laboratories). Samples
were incubated overnight at 4°C with primary antibodies. After washing in
PBS, cultures were incubated with the appropriate secondary antibody, 1:100
(Jackson ImmunoResearch Laboratories, West Grove, PA): Cy3-anti-mouse IgG,
FITC-anti-mouse IgG, Cy3-anti-rat IgG, Cy3-anti-rabbit IgG, or
FITC-anti-rabbit IgG, for 1 hour at room temperature. The cultures were washed
in PBS and mounted for analysis with a confocal microscope.
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Results |
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E-cadherin restores normal morphology and adhesion in N-cadherin-null
myocytes
As previously described (Luo et al.,
2001), the human gene for E-cadherin expressed from the MHC
promoter results in cardiac-specific expression in the primitive heart tube.
Heterozygous N-cadherin mice with or without the
MHC/Ecad transgene
were backcrossed to N-cadherin heterozygotes, and embryos recovered at E9
(Ncad/) or E10 (Ncad/;
Ecad+). Heart tubes were isolated, cells disassociated, and
examined after 3 days in culture. The frequency of viable cultures obtained
from the N-cadherin mutant embryos was low, probably due to the poor yield of
myocytes from the developmentally delayed mutant embryos. Approximately 80% of
the cells in culture were myocytes as determined by immunostaining for
sarcomeric myosin (data not shown). Wild-type myocytes attached and spread
extensively on fibronectin-coated cover slips and formed tightly adherent
aggregates (Fig. 1A). By
contrast, only a subset of N-cadherin-null myocytes attached and spread,
forming small aggregates (Fig.
1B); however, many cells either never attached or initially
attached and eventually rounded up and detached from the substrate
(Fig. 1C). The mutant myocytes
continued to beat, albeit weakly, demonstrating their viability. Consistent
with this observation, we had previously shown no increase in apoptosis in
mutant myocytes in vivo (Luo et al.,
2001
). Normal cell-cell contacts and morphology were restored in
the N-cadherin-null myocytes expressing the
MHC/Ecad transgene
(Fig. 1D). Similar to wild-type
cultures, large aggregates of these myocytes were generated by
E-cadherin-mediated adhesion.
|
Catenin expression is severely reduced in N-cadherin-deficient
myocytes
Cadherins and catenins are coordinately regulated in cells. To investigate
the expression and distribution of catenins in N-cadherin-null and rescued
myocytes, immunohistochemistry was performed on the myocyte cultures.
Consistent with N-cadherin being the primary cadherin present in myocytes,
ß-catenin and p120ctn were significantly reduced or absent at the cell
membrane in the N-cadherin-null myocytes
(Fig. 2B,E) compared with
wild-type (Fig. 2A,D).
E-cadherin expression restored catenin expression to normal levels in the
mutant myocytes (Fig. 2C,F),
verifying the co-regulation of these molecules.
|
N-cadherin-mediated adhesion is not required for
myofibrillogenesis
Antibody perturbation experiments in chicken cardiomyocyte cultures
suggested that N-cadherin was required for the formation
(Imanaka-Yoshida et al., 1998)
and maintenance of normal myofibril organization
(Goncharova et al., 1992
;
Peralta Soler and Knudsen,
1994
). Here, we examine myofibril structure in myocytes
genetically null for N-cadherin. Cultures were stained with phalloidin
(Fig. 3A,C), which binds
F-actin in the I-bands, and with antibodies against sarcomeric
-actinin, a component of the Z-disk
(Fig. 3B,D). In the absence of
N-cadherin, the striated pattern of these myofibril components appeared
normal, in contrast to predictions from previous experiments using N-cadherin
function-blocking antibodies. Note the thicker-appearing myofibrils in the
N-cadherin-deficient cells compared with wild-type, which might reflect the
inability of the myocytes to remain well spread. We conclude that N-cadherin
is not required for myofibrillogenesis, suggesting that other cell adhesion
mechanisms (i.e. focal adhesions, Fig.
6) might be sufficient to promote myofibril formation in the
absence of N-cadherin.
|
|
Cadherin function is required for myofibril alignment between
myocytes
For the myocardium to function normally, myofibrils must be aligned across
the plasma membrane from one cell to the next, allowing efficient coordinated
contraction of the muscle. Small aggregates of myocytes were examined for
myofibril organization to determine why the N-cadherin-null aggregates
appeared to contract more weakly compared with wild-type aggregates. The
myocytes were double stained with phalloidin and cadherin, in the case of
wild-type and rescued myocytes, and staining of a desmosomal protein was used
to delineate the cell membrane in the mutant myocytes. The myofibrils of
wild-type myocytes inserted into the plasma membrane, as demonstrated by the
merged image of N-cadherin and F-actin
(Fig. 4C). The myofibers
appeared to run continuously from one cell to the next through regions of
cadherin-mediated cell-cell contact. By contrast, although myofibrils appeared
well formed in the mutant myocytes, they were not anchored at the cell
membrane and their orientation was random with respect to their neighbors
(Fig. 4E,F). E-cadherin was
capable of anchoring the myofibers into the plasma membrane, thus restoring
myofibril alignment between the rescued cells
(Fig. 4I) and demonstrating
that a non-muscle cadherin can substitute for N-cadherin in myocytes. As
reported for N-cadherin (Goncharova et
al., 1992), E-cadherin was also found localized to costameres as
illustrated by its periodic striations at the dorsal surface of the rescued
myocytes (Fig. 4J). In
addition, the Z-disks were properly organized in the E-cadherin-rescued
myocytes as demonstrated by sarcomeric
-actinin staining (data not
shown). Taken together, we have shown using genetically modified myocytes that
cadherin-mediated adhesion is required for myofibril organization between
cells, but not formation within them.
|
Gap junction protein Cx43 is downregulated in N-cadherin-null
myocytes
On the basis of previous studies, it has been proposed that cell-cell
contact mediated by N-cadherin is a prerequisite to gap junction formation in
myocytes (Hertig et al.,
1996a; Kostin et al.,
1999
; Zuppinger et al.,
2000
). Given the significant reduction of catenins in the
N-cadherin-null cells (Fig. 2),
we concluded that N-cadherin was the primary cadherin expressed by
cardiomyocytes, therefore we decided to examine gap junction formation in
these cells. To examine the presence of gap junctions in the myocytes, the
cultures were immunostained with antibodies against Cx43. The characteristic
punctate staining of Cx43 at regions of cell-cell contact was reduced in the
N-cadherin-null myocytes (Fig.
5B) compared with wild-type cells
(Fig. 5A). E-cadherin-mediated
adhesion restored Cx43 to normal levels in the mutant myocytes
(Fig. 5C). Although Cx43 was
reduced, the ability of small aggregates of mutant myocytes to beat
synchronously demonstrated that the cells remained electrically coupled.
|
Cell-ECM interactions appear normal in N-cadherin-deficient
myocytes
Previous studies have indicated that ECM components play an important role
in assembly and/or maintenance of myocyte cytoarchitecture
(Hilenski et al., 1992;
Imanaka-Yoshida et al., 1999
;
Shiraishi et al., 1997
). In
addition, it has been proposed that focal adhesions might serve as nucleation
sites for the assembly of myofibrils (Lin
et al., 1989
). To examine cell-ECM interactions, cultures were
double stained with ß1 integrin and vinculin, and visualized on the
ventral surface of the cell. Although mutant myocytes often appeared less well
spread compared with wild-type, focal contacts looked normal as demonstrated
by the colocalization of ß1 integrin and vinculin in typical adhesion
plaques (Fig. 6C,D). The focal
contacts in E-cadherin-expressing mutant myocytes also appeared normal
(Fig. 6E,F). The presence of
focal adhesions suggests a possible explanation for the normal
myofibrillogenesis observed in the N-cadherin-null myocytes since they may
provide nucleation sites for myofibril assembly.
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Discussion |
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We also examined N-cadherin-null myocytes expressing the MHC/Ecad
transgene (Luo et al., 2001
).
In addition to rescuing the cell adhesion defect, the epithelial cadherin
E-cadherin also anchored myofibrils into the plasma membrane, demonstrating
that N- and E-cadherin are functionally interchangeable in this system. This
result is rather surprising given that E-cadherin is primarily expressed in
epithelial cells and normally not found in muscle. By contrast, N-cadherin is
found primarily in muscle and neuronal cell lineages. N- and E-cadherin show
about 50% amino acid similarity overall
(Miyatani et al., 1989
), with
the highest degree of conservation in the cytoplasmic domain (62%). It is
interesting that the E-cadherin/catenin complex can support the insertion of
myofibrils into the plasma membrane of N-cadherin-deficient myocytes,
suggesting that the interaction of the cadherin/catenin complex with the
myofibril is not cadherin-subtype specific. In support of our findings, it is
interesting to note that, in Drosophila, in contrast to vertebrates,
DE-cadherin is expressed in cardial cells instead of DN-cadherin
(Iwai et al., 1997
;
Tepass et al., 1996
).
Classical cadherins are defined by their ability to bind catenins at their
cytoplasmic tail, thus linking the cadherin/catenin complex to the actin
cytoskeleton. In contrast to skeletal muscle, which expresses multiple
cadherin subtypes, cardiac muscle appears to depend on one classical cadherin,
N-cadherin. Consistent with this idea, ß-catenin and p120ctn staining was
greatly reduced at regions of cell-cell contact in the N-cadherin-null
myocytes. Furthermore, expression of the MHC/E-cadherin transgene in
mutant myocytes restored catenins to normal levels, demonstrating the
coordinate regulation of the cadherin/catenin complex. On the basis of the
significant reduction in the cadherin/catenin complex in the mutant myocytes,
we proposed that the integrin-based cytoskeletal network provides the
nucleation sites at the plasma membrane necessary for myofibril assembly.
In vitro studies using function-blocking antibodies have shown that
cadherin-mediated adhesion is important for gap junction development
(Frenzel and Johnson, 1996;
Jongen et al., 1991
;
Meyer et al., 1992
). Other
studies, using adult rat cardiomyocytes (ARC), correlated the appearance of
endogenous (Hertig et al.,
1996b
; Kostin et al.,
1999
) or a GFP-tagged N-cadherin
(Zuppinger et al., 2000
) at
regions of cell-cell contact as a prerequisite for gap junction formation.
Furthermore, introduction of a dominant-negative cadherin into ARC resulted in
disruption of gap junctions (Hertig et
al., 1996b
). In the present study, we observed a reduction in gap
junctions as depicted by loss of Cx43 cell-surface staining consistent with a
role for the cadherin/catenin complex in channel formation. Although Cx43
expression is reduced in mutant myocytes, their ability to beat in synchrony
demonstrates that gap junction communication remains operative at some level,
at least sufficient to electrically couple the cells. Our studies indicate
that gap junctions are reduced but still present in N-cadherin-deficient
myocytes, suggesting that other cell adhesion molecules (i.e. N-CAM) are
sufficient to bring cells in close apposition, a prerequisite for gap junction
formation. Interestingly, we previously found no reduction in Cx43 gap
junctions in N-cadherin-deficient neural crest cells, consistent with the
expression of other cadherins in these cells
(Xu et al., 2001
).
Nonetheless, there was a significant reduction in gap junction communication
in the N-cadherin-null neural crest cells as determined by dye coupling
between the cells. Therefore, the function of the remaining gap junctions in
the N-cadherin-deficient myocytes remain to be determined in future
studies.
Together, cadherins and integrins are thought to regulate cell adhesion
during cell migration as demonstrated in neural crest cells
(Monier-Gavelle and Duband,
1997) and myoblasts
(Huttenlocher et al., 1998
).
In myocytes, in addition to its localization at adherens junctions, N-cadherin
is found at costameres (i.e. attachment sites of peripheral myofibrils to the
plasma membrane) similar to integrin. We found that E-cadherin also localized
to costameric sites on the dorsal surface of the N-cadherin-deficient myocytes
containing the
MHC/Ecad transgene. It is unclear how these two adhesion
systems might cooperate to stabilize the contractile apparatus; however, our
present studies and similar studies performed with myocytes mutant for ß1
integrin suggest distinct roles for these adhesion systems. In contrast to
N-cadherin-null cells, cardiomyocytes lacking ß1 integrin displayed
disorganized sarcomeric structures in culture
(Fassler et al., 1996
). In the
same study, ß1 integrin-null myocytes were capable of contributing to the
developing heart of chimeric embryos; by contrast, N-cadherin-deficient
myocytes were excluded from the myocardium
(Kostetskii et al., 2001
).
In our system, the distribution of focal adhesion plaques appeared similar in wild-type, mutant and rescued myocytes. Although focal contacts were present in the mutant myocytes, the cells often appeared less well spread compared with wild-type, suggesting that these structures may be less stable due to the lack of cadherin/cytoskeletal interactions. It is possible that loss of structural support from the cell periphery (i.e. less attachment sites for cortical actin) might cause retraction and subsequent compression of the myofibrils, resulting in their thicker appearance. Alternatively, the loss of N-cadherin-based costameres may perturb the cytoarchitecture, leading to subtle alterations in myofibril structure in the N-cadherin-null myocytes.
In summary, we provide genetic evidence that N-cadherin is not essential for myofibrillogenesis but that cadherin function is required for myofibril alignment between myocytes. The integrin-based focal adhesions are probably sufficient to provide nucleation sites for myofibril assembly, thus explaining the normal striated appearance of the myofibrils in the N-cadherin-null myocytes.
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Acknowledgments |
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References |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Anastasiadis, P. Z. and Reynolds, A. B. (2000).
The p120 catenin family: complex roles in adhesion, signaling and cancer.
J. Cell Sci. 113,1319
-1334.
Carver, W., Price, R. L., Raso, D. S., Terracio, L. and Borg, T.
K. (1994). Distribution of beta-1 integrin in the developing
rat heart. J. Histochem. Cytochem.
42,167
-175.
Conacci-Sorrell, M., Zhurinsky, J. and Ben-Ze'ev, A.
(2002). The cadherin-catenin adhesion system in signaling and
cancer. J. Clin. Invest.
109,987
-991.
Dlugosz, A. A., Antin, P. B., Nachmias, V. T. and Holtzer, H. (1984). The relationship between stress fiber-like structures and nascent myofibrils in cultured cardiac myocytes. J. Cell Biol. 99,2268 -2278.[Abstract]
Duband, J. L., Volberg, T., Sabanay, I., Thiery, J. P. and Geiger, B. (1988). Spatial and temporal distribution of the adherens-junction-associated adhesion molecule A-CAM during avian embryogenesis. Development 103,325 -344.[Abstract]
Epstein, H. F. and Fischman, D. A. (1991). Molecular analysis of protein assembly in muscle development. Science 251,1039 -1044.[Medline]
Fassler, R., Rohwedel, J., Maltsev, V., Bloch, W., Lentini, S.,
Guan, K., Gullberg, D., Hescheler, J., Addicks, K. and Wobus, A. M.
(1996). Differentiation and integrity of cardiac muscle cells are
impaired in the absence of beta 1 integrin. J. Cell
Sci. 109,2989
-2999.
Ferreira-Cornwell, M. C., Luo, Y., Narula, N., Lenox, J. M.,
Lieberman, M. and Radice, G. L. (2002). Remodeling the
intercalated disc leads to cardiomyopathy in mice misexpressing cadherins in
the heart. J. Cell Sci.
115,1623
-1634.
Frenzel, E. M. and Johnson, R. G. (1996). Gap junction formation between cultured embryonic lens cells is inhibited by antibody to N-cadherin. Dev. Biol. 179, 1-16.[CrossRef][Medline]
Geiger, B. (1979). A 130K protein from chicken gizzard: its localization at the termini of microfilament bundles in cultured chicken cells. Cell 18,193 -205.[Medline]
Goncharova, E. J., Kam, Z. and Geiger, B. (1992). The involvement of adherens junction components in myofibrillogenesis in cultured cardiac myocytes. Development 114,173 -183.[Abstract]
Gulick, J., Subramaniam, A., Neumann, J. and Robbins, J.
(1991). Isolation and characterization of the mouse cardiac
myosin heavy chain genes. J. Biol. Chem.
266,9180
-9185.
Gumbiner, B. M. (2000). Regulation of cadherin
adhesive activity. J. Cell Biol.
148,399
-403.
Hatta, K., Takagi, S., Fujisawa, H. and Takeichi, M. (1987). Spatial and temporal expression pattern of N-cadherin cell adhesion molecules correlated with morphogenetic processes of chicken embryos. Dev. Biol. 120,215 -227.[Medline]
Hertig, C. M., Butz, S., Koch, S., Eppenberger-Eberhardt, M.,
Kemler, R. and Eppenberger, H. M. (1996a). N-cadherin in
adult rat cardiomyocytes in culture. II. Spatio-temporal appearance of
proteins involved in cell-cell contact and communication. Formation of two
distinct N-cadherin/catenin complexes. J. Cell Sci.
109, 11-20.
Hertig, C. M., Eppenberger-Eberhardt, M., Koch, S. and
Eppenberger, H. M. (1996b). N-cadherin in adult rat
cardiomyocytes in culture. I. Functional role of N-cadherin and impairment of
cell-cell contact by a truncated N-cadherin mutant. J. Cell
Sci. 109,1
-10.
Hilenski, L. L., Ma, X. H., Vinson, N., Terracio, L. and Borg, T. K. (1992). The role of beta 1 integrin in spreading and myofibrillogenesis in neonatal rat cardiomyocytes in vitro. Cell Motil. Cytoskeleton 21,87 -100.[Medline]
Huttenlocher, A., Lakonishok, M., Kinder, M., Wu, S., Truong,
T., Knudsen, K. A. and Horwitz, A. F. (1998). Integrin
and cadherin synergy regulates contact inhibition of migration and motile
activity. J. Cell Biol.
141,515
-526.
Imanaka-Yoshida, K., Knudsen, K. A. and Linask, K. K. (1998). N-cadherin is required for the differentiation and initial myofibrillogenesis of chick cardiomyocytes. Cell Motil. Cytoskeleton 39,52 -62.[CrossRef][Medline]
Imanaka-Yoshida, K., Enomoto-Iwamoto, M., Yoshida, T. and
Sakakura, T. (1999). Vinculin, talin, integrin
6ß1 and laminin can serve as components of attachment complex
mediating contraction force transmission from cardiomyocytes to extracellular
matrix. Cell Motil. Cytoskeleton
42, 1-11.[CrossRef][Medline]
Iwai, Y., Usui, T., Hirano, S., Steward, R., Takeichi, M. and Uemura, T. (1997). Axon patterning requires DN-cadherin, a novel neuronal adhesion receptor, in the Drosophila embryonic CNS. Neuron 19,77 -89.[Medline]
Janssens, B., Goossens, S., Staes, K., Gilbert, B., van Hengel,
J., Colpaert, C., Bruyneel, E., Mareel, M. and van Roy, F.
(2001). T-catenin: a novel tissue-specific
beta-catenin-binding protein mediating strong cell-cell adhesion.
J. Cell Sci. 114,3177
-3188.
Jongen, W. M., Fitzgerald, D. J., Asamoto, M., Piccoli, C., Slaga, T. J., Gros, D., Takeichi, M. and Yamasaki, H. (1991). Regulation of connexin 43-mediated gap junctional intercellular communication by Ca2+ in mouse epidermal cells is controlled by E-cadherin. J. Cell Biol. 114,545 -555.[Abstract]
Knudsen, K. A., Soler, A. P., Johnson, K. R. and Wheelock, M.
J. (1995). Interaction of -actinin with the
cadherin/catenin cell-cell adhesion complex via
-catenin. J.
Cell Biol. 130,67
-77.[Abstract]
Kostetskii, I., Moore, R., Kemler, R. and Radice, G. L. (2001). Differential adhesion leads to segregation and exclusion of N-cadherin-deficient cells in chimeric embryos. Dev. Biol. 234,72 -79.[CrossRef][Medline]
Kostin, S., Hein, S., Bauer, E. P. and Schaper, J.
(1999). Spatiotemporal development and distribution of
intercellular junctions in adult rat cardiomyocytes in culture.
Circ. Res. 85,154
-167.
Lin, Z. X., Holtzer, S., Schultheiss, T., Murray, J., Masaki, T., Fischman, D. A. and Holtzer, H. (1989). Polygons and adhesion plaques and the disassembly and assembly of myofibrils in cardiac myocytes. J. Cell Biol. 108,2355 -2367.[Abstract]
Lu, M. H., DiLullo, C., Schultheiss, T., Holtzer, S., Murray, J. M., Choi, J., Fischman, D. A. and Holtzer, H. (1992). The vinculin/sarcomeric-alpha-actinin/alpha-actin nexus in cultured cardiac myocytes. J. Cell Biol. 117,1007 -1022.[Abstract]
Luo, Y., Ferreira-Cornwell, M., Baldwin, H., Kostetskii, I.,
Lenox, J., Lieberman, M. and Radice, G. (2001).
Rescuing the N-cadherin knockout by cardiac-specific expression of N- or
E-cadherin. Development
128,459
-469.
Meyer, R. A., Laird, D. W., Revel, J. P. and Johnson, R. G. (1992). Inhibition of gap junction and adherens junction assembly by connexin and A-CAM antibodies. J. Cell Biol. 119,179 -189.[Abstract]
Miyatani, S., Shimamura, K., Hatta, M., Nagafuchi, A., Nose, A. and Matsunaga, M. (1989). Neural cadherin: role in selective cell-cell adhesion. Science 245,631 -635.[Medline]
Monier-Gavelle, F. and Duband, J. L. (1997).
Cross talk between adhesion molecules: control of N-cadherin activity by
intracellular signals elicited by ß1 and ß3 integrins in migrating
neural crest cells. J. Cell Biol.
137,1663
-1681.
Pardo, J. V., Siliciano, J. D. and Craig, S. W. (1983). Vinculin is a component of an extensive network of myofibril-sarcolemma attachment regions in cardiac muscle fibers. J. Cell Biol. 97,1081 -1088.[Abstract]
Peralta Soler, A. and Knudsen, K. A. (1994). N-cadherin involvement in cardiac myocyte interaction and myofibrillogenesis. Dev. Biol. 162,9 -17.[CrossRef][Medline]
Radice, G. L., Rayburn, H., Matsunami, H., Knudsen, K. A., Takeichi, M. and Hynes, R. O. (1997). Developmental defects in mouse embryos lacking N-cadherin. Dev. Biol. 181, 64-78.[CrossRef][Medline]
Rhee, D., Sanger, J. M. and Sanger, J. W. (1994). The premyofibril: evidence for its role in myofibrillogenesis. Cell Motil. Cytoskeleton 28, 1-24.[Medline]
Rimm, D. L., Koslov, E. R., Kebriaei, P., Cianci, C. D. and
Morrow, J. S. (1995). 1(E)-catenin is an actin-binding
and -bundling protein mediating the attachment of F-actin to the membrane
adhesion complex. Proc. Natl. Acad. Sci. USA
92,8813
-8817.[Abstract]
Ross, R. S. and Borg, T. K. (2001). Integrins
and the myocardium. Circ. Res.
88,1112
-1119.
Shai, S. Y., Harpf, A. E., Babbitt, C. J., Jordan, M. C.,
Fishbein, M. C., Chen, J., Omura, M., Leil, T. A., Becker, K. D., Jiang, M. et
al. (2002). Cardiac myocyte-specific excision of the ß1
integrin gene results in myocardial fibrosis and cardiac failure.
Circ. Res. 90,458
-464.
Shan, W. S., Tanaka, H., Phillips, G. R., Arndt, K., Yoshida,
M., Colman, D. R. and Shapiro, L. (2000). Functional
cis-heterodimers of N- and R-cadherins. J. Cell Biol.
148,579
-590.
Shiraishi, I., Simpson, D. G., Carver, W., Price, R., Hirozane, T., Terracio, L. and Borg, T. K. (1997). Vinculin is an essential component for normal myofibrillar arrangement in fetal mouse cardiac myocytes. J. Mol. Cell. Cardiol. 29,2041 -2052.[CrossRef][Medline]
Tepass, U., Gruszynski-DeFeo, E., Haag, T. A., Omatyar, L., Torok, T. and Hartenstein, V. (1996). shotgun encodes Drosophila E-cadherin and is preferentially required during cell rearrangement in the neuroectoderm and other morphogenetically active epithelia. Genes Dev. 10,672 -685.[Abstract]
Tepass, U., Truong, K., Godt, D., Ikura, M. and Peifer, M. (2000). Cadherins in embryonic and neural morphogenesis. Nat. Rev. Mol. Cell. Biol. 1, 91-100.[CrossRef][Medline]
Terracio, L., Rubin, K., Gullberg, D., Balog, E., Carver, W., Jyring, R. and Borg, T. K. (1991). Expression of collagen binding integrins during cardiac development and hypertrophy. Circ. Res. 68,734 -744.[Abstract]
Volk, T. and Geiger, B. (1984). A 135-kd membrane protein of intercellular adherens junctions. EMBO J. 3,2249 -2260.[Abstract]
Volk, T. and Geiger, B. (1986). A-CAM: a 135-kD receptor of intercellular adherens junctions. I. Immunoelectron microscopic localization and biochemical studies. J. Cell Biol. 103,1441 -1450.[Abstract]
Watabe-Uchida, M., Uchida, N., Imamura, Y., Nagafuchi, A.,
Fujimoto, K., Uemura, T., Vermeulen, S., van Roy, F., Adamson, E. D.
and Takeichi, M. (1998). alpha-Catenin-vinculin interaction
functions to organize the apical junctional complex in epithelial cells.
J. Cell Biol. 142,847
-857.
Wu, J.-C., Chung, T.-H., Tseng, Y.-Z. and Wang, S.-M. (1999). N-cadherin/catenin-based costameres in cultured chicken cardiomyocytes. J. Cell. Biochem. 75, 93-104.[CrossRef][Medline]
Wu, J.-C., Sung, H.-C., Chung, T.-H. and DePhilip, R. M. (2002). Role of N-cadherin- and integrin-based costameres in the development of rat cardiomyocytes. J. Cell. Biochem. 84,717 -724.[CrossRef][Medline]
Xu, X., Li, W. E., Huang, G. Y., Meyer, R., Chen, T., Luo, Y.,
Thomas, M. P., Radice, G. L. and Lo, C. W. (2001).
Modulation of mouse neural crest cell motility by N-cadherin and connexin 43
gap junctions. J. Cell Biol.
154,217
-230.
Zuppinger, C., Schaub, M. C. and Eppenberger, H. M. (2000). Dynamics of early contact formation in cultured adult rat cardiomyocytes studied by N-cadherin fused to green fluorescent protein. J. Mol. Cell. Cardiol. 32,539 -555.[CrossRef][Medline]