Roles of cell-adhesion molecules nectin 1 and nectin 3 in ciliary body development.
Nectins are Ca2+-independent immunoglobulin-like cell-cell-adhesion molecules consisting of four members. Nectins homophilically and heterophilically trans-interact to form a variety of cell-cell junctions, including cadherin-based adherens junctions in epithelial cells and fibroblasts in culture, synaptic junctions in neurons, and Sertoli cell-spermatid junctions in the testis, in cooperation with, or independently of, cadherins. To further explore the function of nectins, we generated nectin 1-/- and nectin 3-/-)mice. Both nectin 1-/- and nectin 3-/- mice showed a virtually identical ocular phenotype, microphthalmia, accompanied by a separation of the apex-apex contact between the pigment and non-pigment cell layers of the ciliary epithelia. Immunofluorescence and immunoelectron microscopy revealed that nectin 1 and nectin 3, but not nectin 2, localized at the apex-apex junctions between the pigment and non-pigment cell layers of the ciliary epithelia. However, nectin 1-/- and nectin 3-/- mice showed no impairment of the apicolateral junctions between the pigment epithelia where nectin 1, nectin 2 and nectin 3 localized, or of the apicolateral junctions between the non-pigment epithelia where nectin 2 and nectin 3, but not nectin 1, localized. These results indicate that the heterophilic trans-interaction between nectin 1 and nectin 3 plays a sentinel role in establishing the apex-apex adhesion between the pigment and non-pigment cell layers of the ciliary epithelia that is essential for the morphogenesis of the ciliary body.
Inagaki
Maiko
M
Department of Molecular Biology and Biochemistry, Osaka University Graduate School of Medicine/Faculty of Medicine, Suita 565-0871, Japan.
Irie
Kenji
K
Ishizaki
Hiroyoshi
H
Tanaka-Okamoto
Miki
M
Morimoto
Koji
K
Inoue
Eiji
E
Ohtsuka
Toshihisa
T
Miyoshi
Jun
J
Takai
Yoshimi
Y
D000818:Animals; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000502:physiology*; D002924:Ciliary Body / Q000196:embryology* / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008850:Microphthalmos / Q000235:genetics / Q000473:pathology; D000075983:Nectins; D012333:RNA, Messenger / Q000502:physiology
D015815:Cell Adhesion Molecules; C000619015:Nectin1 protein, mouse; C000619017:Nectin3 protein, mouse; D000075983:Nectins; D012333:RNA, Messenger