title: Fibulin-5 contributes to microfibril assembly in human periodontal ligament cells.
abstract: The elastic system fibers comprise oxytalan, elaunin and elastic fibers, which differ in their relative microfibril and elastin content. Human periodontal ligaments (PDL) contain only oxytalan fibers (pure microfibrils) among them. Since fibulin-5 regulates the organization of elastic fibers to link the fibers to cells, we hypothesized that fibulin-5 may contribute to the formation of oxytalan fibers. We used siRNA for fibulin-5 in PDL cell culture to examine the extracellular deposition of fibrillin-1 and -2, which are the major components of microfibrils. Fibulin-5 was labeled on microfibrils positive for fibrillin-1 and -2. Fibulin-5 suppression reduced the level of fibrillin-1 and -2 deposition to 60% of the control level. These results suggest that fibulin-5 may control the formation of oxytalan fibers, and play a role in the homeostasis of oxytalan fibers.
authors.affiliation: 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.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Hisanaga
authors.forename: Kazuki
authors.initials: K
authors.lastname: Nakashima
authors.forename: Eichi
authors.initials: E
authors.lastname: Tsuruga
authors.forename: Yuka
authors.initials: Y
authors.lastname: Nakatomi
authors.forename: Yuji
authors.initials: Y
authors.lastname: Hatakeyama
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ishikawa
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Sawa