Microfibril-associated glycoprotein-1 controls human ciliary zonule development in vitro.
The ciliary zonule in the eye, also known as Zinn's zonule, is composed of oxytalan fibers, which are bundles of microfibrils consisting mainly of fibrillin-1. However, it is still unclear which of the microfibril-associated molecules present in the ciliary zonule controls oxytalan fibers. Microfibril-associated glycoprotein-1 (MAGP-1) is the only microfibril-associated molecule identified in the human ciliary zonule. In the present study, we used siRNA against MAGP-1 in cultures of human non-pigmented ciliary epithelial cells to examine the extracellular deposition and appearance of fibrillin-1 employing Western blotting and immunofluorescence. MAGP-1 suppression led to a reduction of fibrillin-1 deposition. Immunofluorescence also confirmed that RNAi-mediated down-regulation of MAGP-1 led to suppression of fiber development. These results suggest that MAGP-1 plays a crucial role in the extracellular deposition of fibrillin-1 during formation of the human ciliary zonule.
Section of Orthodontics, Department of Oral Growth & Development, Division of Clinical Dentistry, Fukuoka Dental College, 2-15-1 Tamura, Sawara-ku, Fukuoka 814-0193, Japan.
Takahiro
T
Fujita
Section of Functional Structure, Department of Morphological Biology, Division of Biomedical Sciences, Fukuoka Dental College, 2-15-1 Tamura, Sawara-ku, Fukuoka 814-0193, Japan.
Eichi
E
Tsuruga
Section of Orthodontics, Department of Oral Growth & Development, Division of Clinical Dentistry, Fukuoka Dental College, 2-15-1 Tamura, Sawara-ku, Fukuoka 814-0193, Japan.
Kaori
K
Yamanouchi
Section of Functional Structure, Department of Morphological Biology, Division of Biomedical Sciences, Fukuoka Dental College, 2-15-1 Tamura, Sawara-ku, Fukuoka 814-0193, Japan.
Yoshihiko
Y
Sawa
Section of Orthodontics, Department of Oral Growth & Development, Division of Clinical Dentistry, Fukuoka Dental College, 2-15-1 Tamura, Sawara-ku, Fukuoka 814-0193, Japan.
Hiroyuki
H
Ishikawa
MAGP-1; ciliary zonule; fibrillin; microfibrils; oxytalan fibers