title: Developmental localization of nephrin in zebrafish and medaka pronephric glomerulus.
abstract: Slit diaphragm (SD) is a highly specialized intercellular junction between podocyte foot processes and plays a crucial role in the formation of the filtration barrier. In this study, we examined the developmental localization of Nephrin, an essential component of SD, in the pronephric glomerulus of zebrafish and medaka. In the mature glomerulus of both fish, Nephrin is localized along the glomerular basement membrane as seen in mammals, indicating that Nephrin is localized at the SD. Interestingly, Nephrin was detected already in immature podocytes before the SD and foot processes started to form in both fish. Nephrin was localized along the cell surface of immature podocytes but as different localization patterns. In zebrafish, Nephrin signal bordered the lateral membrane of podocytes, which were columnar in shape, as in rat immature podocytes. However, in medaka immature podocytes, Nephrin was localized in a punctate pattern among podocyte cell bodies. These findings suggest that Nephrin needs to be integrated to the membrane before the formation of the SD and then moves to the proper site to form the SD. Furthermore, a podocyte-specific marker, such as Nephrin, should be a useful tool for the future analysis of pronephric glomerular development in fish mutants and morphants.
authors: Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA.
authors: Koichiro
authors: K
authors: Ichimura
authors: Yayoi
authors: Y
authors: Fukuyo
authors: Tomomi
authors: T
authors: Nakamura
authors: Rebecca
authors: R
authors: Powell
authors: Tatsuo
authors: T
authors: Sakai
authors: Ralf
authors: R
authors: Janknecht
authors: Tomoko
authors: T
authors: Obara
mesh_terms: D000818:Animals; D008565:Membrane Proteins / Q000032:analysis*; D009990:Oryzias / Q000378:metabolism*; D050199:Podocytes / Q000737:chemistry* / Q000166:cytology; D015027:Zebrafish / Q000378:metabolism*
chemical_list: D008565:Membrane Proteins; C113267:nephrin