N-cadherin expression in palisade nerve endings of rat vellus hairs

Division of Morphological Analysis, Department of Functional, Morphological and Regulatory Science, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan.
The Journal of Comparative Neurology (Impact Factor: 3.23). 02/2008; 506(4):525-34. DOI: 10.1002/cne.21550
Source: PubMed


Palisade nerve endings (PNs) are mechanoreceptors around vellus hairs of mammals. Each lanceolate nerve ending (LN) of the PN is characterized by a sensory nerve ending symmetrically sandwiched by two processes of type II terminal Schwann cells (tSCIIs). However, the molecular mechanisms underlying the structural organization of the PN are poorly understood. Electron microscopy showed that adherens junctions appeared to adhere to the sensory nerve ending and tSCII processes, so we examined the location of the N-cadherin adhesion system in PNs of rat vellus hairs by using immunoelectron microscopy. N-cadherin localized near both ends of the cell boundary between sensory nerve ending and tSCII processes, which corresponded to the sites of adherens junctions. We further found cadherin-associated proteins, alpha- and beta-catenins, at the linings of adherens junctions. Three-dimensional reconstruction of immunoelectron microscopic serial thin sections showed four linear arrays of N-cadherin arranged longitudinally along the LN beneath the four longitudinal borders of two tSCII processes. In contrast, sensory nerve fibers just proximal to the LNs formed common unmyelinated nerve fibers, in which N-cadherin was located mainly at the mesaxon of type I terminal Schwann cells (tSCIs). These results suggest that the four linear arrays of N-cadherin-mediated junctions adhere the sensory nerve ending and tSCII processes side by side to form the characteristic structure of the LN, and the structural differences between the LNs and the proximal unmyelinated nerve fibers possibly are due to the difference in the pattern of N-cadherin expression between sensory nerve endings and tSCII or tSCI processes.

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    • "Also, ADAM10 has been confirmed as a candidate alpha-secretase responsible for shedding proteins such as cadherins (Reiss et al., 2005, 2006; Schulz et al., 2008). It has been shown previously that Notch/Delta, cadherins, and their intracellular binding partners, the catenins, are involved in hair and feather development (Crowe et al., 1998; Noramly et al., 1999; Chodankar et al., 2003; Kaidoh and Inoué, 2008). For example , similar to ADAM10, beta-catenin is expressed in the epidermal layer of the feather buds (Wu et al., 2008). "
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    Developmental Dynamics 09/2011; 240(9):2142-52. DOI:10.1002/dvdy.22703 · 2.38 Impact Factor
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    • "Merkel cells were also strongly labeled, but axons associated with the Merkel cells were never visible. Finally, intense NTPDase3 immunoreactivity was seen in terminal Schwann cells surrounding the bases of hair follicles, clearly identifiable by their unique morphology and bulb-like cell body (Fig. 5B; see also Kaidoh and Inoué, 2008). These Schwann cells envelop the lanceolate endings of myelinated hair follicle afferents; however, the axons themselves were not labeled. "
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    Neuroscience 07/2011; 193:387-98. DOI:10.1016/j.neuroscience.2011.07.044 · 3.36 Impact Factor
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    • "This is the case around Merkel cells, in Ruffini corpuscles and at the pilo-neural complexes . The presence of two types of terminal Schwann cells around the hair follicle was previously reported (Kaidoh and Inoue, 2008). Heterogeneity between the two types of tSCs is emphasized by collagen XXVIII expression since it surrounds only tSCI, thereby allowing to discriminate these two types of tSCs. "
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