title: Syntenin is expressed in human follicular dendritic cells and involved in the activation of focal adhesion kinase.
abstract: Syntenin is an adaptor molecule containing 2 PDZ domains which mediate molecular interactions with diverse integral or cytoplasmic proteins. Most of the results on the biological function of syntenin were obtained from studies with malignant cells, necessitating exploration into the role of syntenin in normal cells. To understand its role in normal cells, we investigated expression and function of syntenin in human lymphoid tissue and cells in situ and in vitro. Syntenin expression was denser in the germinal center than in the extrafollicular area. Inside the germinal center, syntenin expression was obvious in follicular dendritic cells (FDCs). Flow cytometric analysis with isolated cells confirmed a weak expression of syntenin in T and B cells and a strong expression in FDCs. In FDC-like cells, HK cells, most syntenin proteins were found in the cytoplasm compared to weak expression in the nucleus. To study the function of syntenin in FDC, we examined its role in the focal adhesion of HK cells by depleting syntenin by siRNA technology. Knockdown of syntenin markedly impaired focal adhesion kinase phosphorylation in HK cells. These results suggest that syntenin may play an important role in normal physiology as well as in cancer pathology.
authors.affiliation: Department of Microbiology and Immunology, Kangwon National University School of Medicine, Chuncheon 200-701, Korea.
authors.forename: Whajung
authors.initials: W
authors.lastname: Cho
authors.forename: Hyeyoung
authors.initials: H
authors.lastname: Kim
authors.forename: Jeong-Hyung
authors.initials: JH
authors.lastname: Lee
authors.forename: Seung Hee
authors.initials: SH
authors.lastname: Hong
authors.forename: Jongseon
authors.initials: J
authors.lastname: Choe
keywords: FAK; Follicular dendritic cell; Syntenin