Cadherin is required for dendritic morphogenesis and synaptic terminal organization of retinal horizontal cells.
Dendrite morphology of neurons provides a structural basis for their physiological characteristics, and is precisely regulated in a cell type-dependent manner. Using a unique transposon-mediated gene transfer system that enables conditional and cell-type specific expression of exogenous genes, we investigated the role of cadherin on dendritic morphogenesis of horizontal cells in the developing chicken retina. We first visualized single horizontal cells by overexpressing membrane-targeted EGFP, and confirmed that there were three subtypes of horizontal cells, the dendritic terminals of which projected to distinct synaptic sites in the outer plexiform layer. Expression of a dominant-negative cadherin decreased the dendritic field size, and perturbed the termination of dendritic processes onto the photoreceptor cells. The cadherin blockade also impaired the accumulation of GluR4, a postsynaptic marker, at the cone pedicles. We thus provide in vivo evidence that cadherin is required for dendrite morphogenesis of horizontal cells and subsequent synapse formation with photoreceptor cells in the vertebrate retina.
Tanabe
Koji
K
RIKEN Center for Developmental Biology, 2-2-3 Minatojima Minamimachi, Chuoku, Kobe 650-0047, Japan.
Takahashi
Yoshiko
Y
Sato
Yuki
Y
Kawakami
Koichi
K
Takeichi
Masatoshi
M
Nakagawa
Shinichi
S
D000818:Animals; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D015820:Cadherins / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D002642:Chick Embryo; D003712:Dendrites / Q000502:physiology* / Q000648:ultrastructure; D015870:Gene Expression; D018014:Gene Transfer Techniques; D049452:Green Fluorescent Proteins / Q000032:analysis / Q000235:genetics; D009024:Morphogenesis / Q000235:genetics; D018091:Receptors, AMPA / Q000032:analysis / Q000378:metabolism; D017949:Retinal Cone Photoreceptor Cells / Q000737:chemistry / Q000378:metabolism; D051248:Retinal Horizontal Cells / Q000737:chemistry / Q000196:embryology* / Q000648:ultrastructure; D013569:Synapses / Q000737:chemistry / Q000648:ultrastructure*
D015415:Biomarkers; D015820:Cadherins; D018091:Receptors, AMPA; C485184:enhanced green fluorescent protein; C104724:glutamate receptor ionotropic, AMPA 4; D049452:Green Fluorescent Proteins