Fluorescence Visualization of Branchial Collagen Columns Embraced by Pillar Cells

Abstract

A collagen column is a structure of the extracellular matrix that helps to maintain the flatness and width of gill lamella. Collagen columns are unique in that they are enfolded by plasma membrane of pillar cells that form two-dimensional vascular networks between parallel sheets of respiratory epithelia. Despite their unique structure and fundamental importance in the physiology of aquatic animals, little is known about their properties and molecular components, owing to the lack of detection methods. In this study we demonstrated that collagen columns can be visualized by staining with fluorescencelabeled concanavalin A (ConA), a lectin that specifically recognizes the trimannoside core of N-glycosylated proteins and histidine-tagged green fluorescent protein (His6-Xpress-GFP), a fluorescent substrate for transglutaminase. We constructed a three-dimensional image of a pillar cell and visualized the spatial relationship between collagen columns and contractile apparatuses within the pillar cell body. This manuscript contains online supplemental material at http://www.jhc.org . Please visit this article online to view these materials.

Occludin immunolocalization and protein expression in goldfish

“…pavement cells or MRCs) and/or with TJs between pillar cells that surround and form the lamellar blood spaces. This generally agrees with previous reports in which freeze fracture and electron microscopy observations of fish gill epithelia have shown that (Hughes and Grimstone, 1965;Sardet et al, 1979;Bartels and Potter, 1991;Kudo et al, 2007). Furthermore, a recent study has immunolocalized ZO-1, which is believed to associate with the C-terminal region of occludin (Furuse et al, 1994), to pillar cells within the gills of marine puffer fish .…”

Comparison of Gene Expression in the Gill of Salmon (Salmo salar) Smolts from Anadromous and Landlocked Populations

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The responses of zebrafish (Danio rerio) to high external ammonia and urea transporter inhibition: nitrogen excretion and expression of rhesus glycoproteins and urea transporter proteins

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